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Merge with docrails

This commit is contained in:
Pratik Naik 2008-12-07 03:27:53 +01:00
parent 9eca588bdf
commit dbbae5e00e
78 changed files with 5231 additions and 1371 deletions

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@ -10,7 +10,7 @@ Action Pack implements these actions as public methods on Action Controllers
and uses Action Views to implement the template rendering. Action Controllers
are then responsible for handling all the actions relating to a certain part
of an application. This grouping usually consists of actions for lists and for
CRUDs revolving around a single (or a few) model objects. So ContactController
CRUDs revolving around a single (or a few) model objects. So ContactsController
would be responsible for listing contacts, creating, deleting, and updating
contacts. A WeblogController could be responsible for both posts and comments.
@ -33,7 +33,7 @@ A short rundown of the major features:
* Actions grouped in controller as methods instead of separate command objects
and can therefore share helper methods
BlogController < ActionController::Base
CustomersController < ActionController::Base
def show
@customer = find_customer
end
@ -42,7 +42,7 @@ A short rundown of the major features:
@customer = find_customer
@customer.attributes = params[:customer]
@customer.save ?
redirect_to(:action => "display") :
redirect_to(:action => "show") :
render(:action => "edit")
end
@ -59,7 +59,7 @@ A short rundown of the major features:
Title: <%= post.title %>
<% end %>
All post titles: <%= @post.collect{ |p| p.title }.join ", " %>
All post titles: <%= @posts.collect{ |p| p.title }.join ", " %>
<% unless @person.is_client? %>
Not for clients to see...
@ -123,7 +123,7 @@ A short rundown of the major features:
<%= text_field "post", "title", "size" => 30 %>
<%= html_date_select(Date.today) %>
<%= link_to "New post", :controller => "post", :action => "new" %>
<%= truncate(post.title, 25) %>
<%= truncate(post.title, :length => 25) %>
{Learn more}[link:classes/ActionView/Helpers.html]
@ -177,21 +177,6 @@ A short rundown of the major features:
{Learn more}[link:classes/ActionView/Helpers/JavaScriptHelper.html]
* Pagination for navigating lists of results
# controller
def list
@pages, @people =
paginate :people, :order => 'last_name, first_name'
end
# view
<%= link_to "Previous page", { :page => @pages.current.previous } if @pages.current.previous %>
<%= link_to "Next page", { :page => @pages.current.next } if @pages.current.next %>
{Learn more}[link:classes/ActionController/Pagination.html]
* Easy testing of both controller and rendered template through ActionController::TestCase
class LoginControllerTest < ActionController::TestCase
@ -215,11 +200,11 @@ A short rundown of the major features:
If Active Record is used as the model, you'll have the database debugging
as well:
Processing WeblogController#create (for 127.0.0.1 at Sat Jun 19 14:04:23)
Params: {"controller"=>"weblog", "action"=>"create",
Processing PostsController#create (for 127.0.0.1 at Sat Jun 19 14:04:23)
Params: {"controller"=>"posts", "action"=>"create",
"post"=>{"title"=>"this is good"} }
SQL (0.000627) INSERT INTO posts (title) VALUES('this is good')
Redirected to http://test/weblog/display/5
Redirected to http://example.com/posts/5
Completed in 0.221764 (4 reqs/sec) | DB: 0.059920 (27%)
You specify a logger through a class method, such as:
@ -256,30 +241,6 @@ A short rundown of the major features:
{Learn more}[link:classes/ActionController/Caching.html]
* Component requests from one controller to another
class WeblogController < ActionController::Base
# Performs a method and then lets hello_world output its render
def delegate_action
do_other_stuff_before_hello_world
render_component :controller => "greeter", :action => "hello_world"
end
end
class GreeterController < ActionController::Base
def hello_world
render_text "Hello World!"
end
end
The same can be done in a view to do a partial rendering:
Let's see a greeting:
<%= render_component :controller => "greeter", :action => "hello_world" %>
{Learn more}[link:classes/ActionController/Components.html]
* Powerful debugging mechanism for local requests
All exceptions raised on actions performed on the request of a local user
@ -336,7 +297,7 @@ A short rundown of the major features:
class WeblogController < ActionController::Base
def create
post = Post.create(params[:post])
redirect_to :action => "display", :id => post.id
redirect_to :action => "show", :id => post.id
end
end
@ -362,7 +323,7 @@ methods:
@posts = Post.find(:all)
end
def display
def show
@post = Post.find(params[:id])
end
@ -372,7 +333,7 @@ methods:
def create
@post = Post.create(params[:post])
redirect_to :action => "display", :id => @post.id
redirect_to :action => "show", :id => @post.id
end
end
@ -385,48 +346,33 @@ request from the web-server (like to be Apache).
And the templates look like this:
weblog/layout.erb:
weblog/layout.html.erb:
<html><body>
<%= yield %>
</body></html>
weblog/index.erb:
weblog/index.html.erb:
<% for post in @posts %>
<p><%= link_to(post.title, :action => "display", :id => post.id %></p>
<p><%= link_to(post.title, :action => "show", :id => post.id) %></p>
<% end %>
weblog/display.erb:
weblog/show.html.erb:
<p>
<b><%= post.title %></b><br/>
<b><%= post.content %></b>
<b><%= @post.title %></b><br/>
<b><%= @post.content %></b>
</p>
weblog/new.erb:
weblog/new.html.erb:
<%= form "post" %>
This simple setup will list all the posts in the system on the index page,
which is called by accessing /weblog/. It uses the form builder for the Active
Record model to make the new screen, which in turn hands everything over to
the create action (that's the default target for the form builder when given a
new model). After creating the post, it'll redirect to the display page using
an URL such as /weblog/display/5 (where 5 is the id of the post).
new model). After creating the post, it'll redirect to the show page using
an URL such as /weblog/5 (where 5 is the id of the post).
== Examples
Action Pack ships with three examples that all demonstrate an increasingly
detailed view of the possibilities. First is blog_controller that is just a
single file for the whole MVC (but still split into separate parts). Second is
the debate_controller that uses separate template files and multiple screens.
Third is the address_book_controller that uses the layout feature to separate
template casing from content.
Please note that you might need to change the "shebang" line to
#!/usr/local/env ruby, if your Ruby is not placed in /usr/local/bin/ruby
Also note that these examples are all for demonstrating using Action Pack on
its own. Not for when it's used inside of Rails.
== Download
The latest version of Action Pack can be found at
@ -460,4 +406,4 @@ And as Jim from Rake says:
Feel free to submit commits or feature requests. If you send a patch,
remember to update the corresponding unit tests. If fact, I prefer
new feature to be submitted in the form of new unit tests.
new feature to be submitted in the form of new unit tests.

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@ -83,15 +83,23 @@ module ActionController #:nodoc:
end
end
# Name can take one of three forms:
# * String: This would normally take the form of a path like "pages/45/notes"
# * Hash: Is treated as an implicit call to url_for, like { :controller => "pages", :action => "notes", :id => 45 }
# * Regexp: Will destroy all the matched fragments, example:
# %r{pages/\d*/notes}
# Ensure you do not specify start and finish in the regex (^$) because
# the actual filename matched looks like ./cache/filename/path.cache
# Regexp expiration is only supported on caches that can iterate over
# all keys (unlike memcached).
# Removes fragments from the cache.
#
# +key+ can take one of three forms:
# * String - This would normally take the form of a path, like
# <tt>"pages/45/notes"</tt>.
# * Hash - Treated as an implicit call to +url_for+, like
# <tt>{:controller => "pages", :action => "notes", :id => 45}</tt>
# * Regexp - Will remove any fragment that matches, so
# <tt>%r{pages/\d*/notes}</tt> might remove all notes. Make sure you
# don't use anchors in the regex (<tt>^</tt> or <tt>$</tt>) because
# the actual filename matched looks like
# <tt>./cache/filename/path.cache</tt>. Note: Regexp expiration is
# only supported on caches that can iterate over all keys (unlike
# memcached).
#
# +options+ is passed through to the cache store's <tt>delete</tt>
# method (or <tt>delete_matched</tt>, for Regexp keys.)
def expire_fragment(key, options = nil)
return unless cache_configured?

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@ -33,28 +33,26 @@ module ActionController #:nodoc:
#
# Additionally, you can expire caches using Sweepers that act on changes in the model to determine when a cache is supposed to be
# expired.
#
# == Setting the cache directory
#
# The cache directory should be the document root for the web server and is set using <tt>Base.page_cache_directory = "/document/root"</tt>.
# For Rails, this directory has already been set to Rails.public_path (which is usually set to <tt>RAILS_ROOT + "/public"</tt>). Changing
# this setting can be useful to avoid naming conflicts with files in <tt>public/</tt>, but doing so will likely require configuring your
# web server to look in the new location for cached files.
#
# == Setting the cache extension
#
# Most Rails requests do not have an extension, such as <tt>/weblog/new</tt>. In these cases, the page caching mechanism will add one in
# order to make it easy for the cached files to be picked up properly by the web server. By default, this cache extension is <tt>.html</tt>.
# If you want something else, like <tt>.php</tt> or <tt>.shtml</tt>, just set Base.page_cache_extension. In cases where a request already has an
# extension, such as <tt>.xml</tt> or <tt>.rss</tt>, page caching will not add an extension. This allows it to work well with RESTful apps.
module Pages
def self.included(base) #:nodoc:
base.extend(ClassMethods)
base.class_eval do
@@page_cache_directory = defined?(Rails.public_path) ? Rails.public_path : ""
##
# :singleton-method:
# The cache directory should be the document root for the web server and is set using <tt>Base.page_cache_directory = "/document/root"</tt>.
# For Rails, this directory has already been set to Rails.public_path (which is usually set to <tt>RAILS_ROOT + "/public"</tt>). Changing
# this setting can be useful to avoid naming conflicts with files in <tt>public/</tt>, but doing so will likely require configuring your
# web server to look in the new location for cached files.
cattr_accessor :page_cache_directory
@@page_cache_extension = '.html'
##
# :singleton-method:
# Most Rails requests do not have an extension, such as <tt>/weblog/new</tt>. In these cases, the page caching mechanism will add one in
# order to make it easy for the cached files to be picked up properly by the web server. By default, this cache extension is <tt>.html</tt>.
# If you want something else, like <tt>.php</tt> or <tt>.shtml</tt>, just set Base.page_cache_extension. In cases where a request already has an
# extension, such as <tt>.xml</tt> or <tt>.rss</tt>, page caching will not add an extension. This allows it to work well with RESTful apps.
cattr_accessor :page_cache_extension
end
end

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@ -283,7 +283,12 @@ module ActionController
# * <tt>:new</tt> - Same as <tt>:collection</tt>, but for actions that operate on the new \resource action.
# * <tt>:controller</tt> - Specify the controller name for the routes.
# * <tt>:singular</tt> - Specify the singular name used in the member routes.
# * <tt>:requirements</tt> - Set custom routing parameter requirements.
# * <tt>:requirements</tt> - Set custom routing parameter requirements; this is a hash of either
# regular expressions (which must match for the route to match) or extra parameters. For example:
#
# map.resource :profile, :path_prefix => ':name', :requirements => { :name => /[a-zA-Z]+/, :extra => 'value' }
#
# will only match if the first part is alphabetic, and will pass the parameter :extra to the controller.
# * <tt>:conditions</tt> - Specify custom routing recognition conditions. \Resources sets the <tt>:method</tt> value for the method-specific routes.
# * <tt>:as</tt> - Specify a different \resource name to use in the URL path. For example:
# # products_path == '/productos'

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@ -83,9 +83,11 @@ module ActionController
# This sets up +blog+ as the default controller if no other is specified.
# This means visiting '/' would invoke the blog controller.
#
# More formally, you can define defaults in a route with the <tt>:defaults</tt> key.
# More formally, you can include arbitrary parameters in the route, thus:
#
# map.connect ':controller/:action/:id', :action => 'show', :defaults => { :page => 'Dashboard' }
# map.connect ':controller/:action/:id', :action => 'show', :page => 'Dashboard'
#
# This will pass the :page parameter to all incoming requests that match this route.
#
# Note: The default routes, as provided by the Rails generator, make all actions in every
# controller accessible via GET requests. You should consider removing them or commenting

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@ -56,6 +56,8 @@ class CGI
class ActiveRecordStore
# The default Active Record class.
class Session < ActiveRecord::Base
##
# :singleton-method:
# Customizable data column name. Defaults to 'data'.
cattr_accessor :data_column_name
self.data_column_name = 'data'
@ -166,17 +168,25 @@ class CGI
# binary session data in a +text+ column. For higher performance,
# store in a +blob+ column instead and forgo the Base64 encoding.
class SqlBypass
##
# :singleton-method:
# Use the ActiveRecord::Base.connection by default.
cattr_accessor :connection
##
# :singleton-method:
# The table name defaults to 'sessions'.
cattr_accessor :table_name
@@table_name = 'sessions'
##
# :singleton-method:
# The session id field defaults to 'session_id'.
cattr_accessor :session_id_column
@@session_id_column = 'session_id'
##
# :singleton-method:
# The data field defaults to 'data'.
cattr_accessor :data_column
@@data_column = 'data'

View file

@ -183,13 +183,17 @@ module ActionView #:nodoc:
@@exempt_from_layout.merge(regexps)
end
@@debug_rjs = false
##
# :singleton-method:
# Specify whether RJS responses should be wrapped in a try/catch block
# that alert()s the caught exception (and then re-raises it).
@@debug_rjs = false
cattr_accessor :debug_rjs
# A warning will be displayed whenever an action results in a cache miss on your view paths.
@@warn_cache_misses = false
##
# :singleton-method:
# A warning will be displayed whenever an action results in a cache miss on your view paths.
cattr_accessor :warn_cache_misses
attr_internal :request

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@ -97,7 +97,7 @@ module ActionView
# Returns an escaped version of +html+ without affecting existing escaped entities.
#
# ==== Examples
# escape_once("1 > 2 &amp; 3")
# escape_once("1 < 2 &amp; 3")
# # => "1 &lt; 2 &amp; 3"
#
# escape_once("&lt;&lt; Accept & Checkout")

View file

@ -3,6 +3,8 @@ module ActionView
class ERB < TemplateHandler
include Compilable
##
# :singleton-method:
# Specify trim mode for the ERB compiler. Defaults to '-'.
# See ERb documentation for suitable values.
cattr_accessor :erb_trim_mode

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@ -24,6 +24,8 @@ module ActiveModel
:even => "must be even"
}
##
# :singleton-method:
# Holds a hash with all the default error messages that can be replaced by your own copy or localizations.
cattr_accessor :default_error_messages

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@ -389,6 +389,8 @@ module ActiveRecord #:nodoc:
# So it's possible to assign a logger to the class through <tt>Base.logger=</tt> which will then be used by all
# instances in the current object space.
class Base
##
# :singleton-method:
# Accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then passed
# on to any new database connections made and which can be retrieved on both a class and instance level by calling +logger+.
cattr_accessor :logger, :instance_writer => false
@ -414,7 +416,9 @@ module ActiveRecord #:nodoc:
end
@@subclasses = {}
##
# :singleton-method:
# Contains the database configuration - as is typically stored in config/database.yml -
# as a Hash.
#
@ -443,6 +447,8 @@ module ActiveRecord #:nodoc:
cattr_accessor :configurations, :instance_writer => false
@@configurations = {}
##
# :singleton-method:
# Accessor for the prefix type that will be prepended to every primary key column name. The options are :table_name and
# :table_name_with_underscore. If the first is specified, the Product class will look for "productid" instead of "id" as
# the primary column. If the latter is specified, the Product class will look for "product_id" instead of "id". Remember
@ -450,34 +456,46 @@ module ActiveRecord #:nodoc:
cattr_accessor :primary_key_prefix_type, :instance_writer => false
@@primary_key_prefix_type = nil
##
# :singleton-method:
# Accessor for the name of the prefix string to prepend to every table name. So if set to "basecamp_", all
# table names will be named like "basecamp_projects", "basecamp_people", etc. This is a convenient way of creating a namespace
# for tables in a shared database. By default, the prefix is the empty string.
cattr_accessor :table_name_prefix, :instance_writer => false
@@table_name_prefix = ""
##
# :singleton-method:
# Works like +table_name_prefix+, but appends instead of prepends (set to "_basecamp" gives "projects_basecamp",
# "people_basecamp"). By default, the suffix is the empty string.
cattr_accessor :table_name_suffix, :instance_writer => false
@@table_name_suffix = ""
##
# :singleton-method:
# Indicates whether table names should be the pluralized versions of the corresponding class names.
# If true, the default table name for a Product class will be +products+. If false, it would just be +product+.
# See table_name for the full rules on table/class naming. This is true, by default.
cattr_accessor :pluralize_table_names, :instance_writer => false
@@pluralize_table_names = true
##
# :singleton-method:
# Determines whether to use ANSI codes to colorize the logging statements committed by the connection adapter. These colors
# make it much easier to overview things during debugging (when used through a reader like +tail+ and on a black background), but
# may complicate matters if you use software like syslog. This is true, by default.
cattr_accessor :colorize_logging, :instance_writer => false
@@colorize_logging = true
##
# :singleton-method:
# Determines whether to use Time.local (using :local) or Time.utc (using :utc) when pulling dates and times from the database.
# This is set to :local by default.
cattr_accessor :default_timezone, :instance_writer => false
@@default_timezone = :local
##
# :singleton-method:
# Specifies the format to use when dumping the database schema with Rails'
# Rakefile. If :sql, the schema is dumped as (potentially database-
# specific) SQL statements. If :ruby, the schema is dumped as an
@ -487,6 +505,8 @@ module ActiveRecord #:nodoc:
cattr_accessor :schema_format , :instance_writer => false
@@schema_format = :ruby
##
# :singleton-method:
# Specify whether or not to use timestamps for migration numbers
cattr_accessor :timestamped_migrations , :instance_writer => false
@@timestamped_migrations = true
@ -640,16 +660,24 @@ module ActiveRecord #:nodoc:
connection.select_all(sanitize_sql(sql), "#{name} Load").collect! { |record| instantiate(record) }
end
# Checks whether a record exists in the database that matches conditions given. These conditions
# can either be a single integer representing a primary key id to be found, or a condition to be
# matched like using ActiveRecord#find.
# Returns true if a record exists in the table that matches the +id+ or
# conditions given, or false otherwise. The argument can take four forms:
#
# The +id_or_conditions+ parameter can be an Integer or a String if you want to search the primary key
# column of the table for a matching id, or if you're looking to match against a condition you can use
# an Array or a Hash.
# * Integer - Finds the record with this primary key.
# * String - Finds the record with a primary key corresponding to this
# string (such as <tt>'5'</tt>).
# * Array - Finds the record that matches these +find+-style conditions
# (such as <tt>['color = ?', 'red']</tt>).
# * Hash - Finds the record that matches these +find+-style conditions
# (such as <tt>{:color => 'red'}</tt>).
#
# Possible gotcha: You can't pass in a condition as a string e.g. "name = 'Jamie'", this would be
# sanitized and then queried against the primary key column as "id = 'name = \'Jamie"
# For more information about specifying conditions as a Hash or Array,
# see the Conditions section in the introduction to ActiveRecord::Base.
#
# Note: You can't pass in a condition as a string (like <tt>name =
# 'Jamie'</tt>), since it would be sanitized and then queried against
# the primary key column, like <tt>id = 'name = \'Jamie\''</tt>.
#
# ==== Examples
# Person.exists?(5)
@ -2320,15 +2348,15 @@ module ActiveRecord #:nodoc:
# object. The default implementation returns this record's id as a String,
# or nil if this record's unsaved.
#
# For example, suppose that you have a Users model, and that you have a
# <tt>map.resources :users</tt> route. Normally, +users_path+ will
# construct an URI with the user object's 'id' in it:
# For example, suppose that you have a User model, and that you have a
# <tt>map.resources :users</tt> route. Normally, +user_path+ will
# construct a path with the user object's 'id' in it:
#
# user = User.find_by_name('Phusion')
# user_path(user) # => "/users/1"
#
# You can override +to_param+ in your model to make +users_path+ construct
# an URI using the user's name instead of the user's id:
# You can override +to_param+ in your model to make +user_path+ construct
# a path using the user's name instead of the user's id:
#
# class User < ActiveRecord::Base
# def to_param # overridden

View file

@ -7,6 +7,8 @@ module ActiveRecord
end
end
##
# :singleton-method:
# The connection handler
cattr_accessor :connection_handler, :instance_writer => false
@@connection_handler = ConnectionAdapters::ConnectionHandler.new

View file

@ -156,13 +156,16 @@ module ActiveRecord
# * <tt>:sslcapath</tt> - Necessary to use MySQL with an SSL connection.
# * <tt>:sslcipher</tt> - Necessary to use MySQL with an SSL connection.
#
# By default, the MysqlAdapter will consider all columns of type <tt>tinyint(1)</tt>
# as boolean. If you wish to disable this emulation (which was the default
# behavior in versions 0.13.1 and earlier) you can add the following line
# to your environment.rb file:
#
# ActiveRecord::ConnectionAdapters::MysqlAdapter.emulate_booleans = false
class MysqlAdapter < AbstractAdapter
##
# :singleton-method:
# By default, the MysqlAdapter will consider all columns of type <tt>tinyint(1)</tt>
# as boolean. If you wish to disable this emulation (which was the default
# behavior in versions 0.13.1 and earlier) you can add the following line
# to your environment.rb file:
#
# ActiveRecord::ConnectionAdapters::MysqlAdapter.emulate_booleans = false
cattr_accessor :emulate_booleans
self.emulate_booleans = true

View file

@ -130,7 +130,9 @@ module ActiveRecord
# To run migrations against the currently configured database, use
# <tt>rake db:migrate</tt>. This will update the database by running all of the
# pending migrations, creating the <tt>schema_migrations</tt> table
# (see "About the schema_migrations table" section below) if missing.
# (see "About the schema_migrations table" section below) if missing. It will also
# invoke the db:schema:dump task, which will update your db/schema.rb file
# to match the structure of your database.
#
# To roll the database back to a previous migration version, use
# <tt>rake db:migrate VERSION=X</tt> where <tt>X</tt> is the version to which

View file

@ -7,6 +7,8 @@ module ActiveRecord
class SchemaDumper #:nodoc:
private_class_method :new
##
# :singleton-method:
# A list of tables which should not be dumped to the schema.
# Acceptable values are strings as well as regexp.
# This setting is only used if ActiveRecord::Base.schema_format == :ruby

View file

@ -494,18 +494,20 @@ module ActiveRecord
# The first_name attribute must be in the object and it cannot be blank.
#
# If you want to validate the presence of a boolean field (where the real values are true and false),
# you will want to use validates_inclusion_of :field_name, :in => [true, false]
# This is due to the way Object#blank? handles boolean values. false.blank? # => true
# you will want to use <tt>validates_inclusion_of :field_name, :in => [true, false]</tt>.
#
# This is due to the way Object#blank? handles boolean values: <tt>false.blank? # => true</tt>.
#
# Configuration options:
# * <tt>message</tt> - A custom error message (default is: "can't be blank").
# * <tt>on</tt> - Specifies when this validation is active (default is <tt>:save</tt>, other options <tt>:create</tt>, <tt>:update</tt>).
# * <tt>on</tt> - Specifies when this validation is active (default is <tt>:save</tt>, other options <tt>:create</tt>,
# <tt>:update</tt>).
# * <tt>if</tt> - Specifies a method, proc or string to call to determine if the validation should
# occur (e.g. :if => :allow_validation, or :if => Proc.new { |user| user.signup_step > 2 }). The
# method, proc or string should return or evaluate to a true or false value.
# occur (e.g. <tt>:if => :allow_validation</tt>, or <tt>:if => Proc.new { |user| user.signup_step > 2 }</tt>).
# The method, proc or string should return or evaluate to a true or false value.
# * <tt>unless</tt> - Specifies a method, proc or string to call to determine if the validation should
# not occur (e.g. :unless => :skip_validation, or :unless => Proc.new { |user| user.signup_step <= 2 }). The
# method, proc or string should return or evaluate to a true or false value.
# not occur (e.g. <tt>:unless => :skip_validation</tt>, or <tt>:unless => Proc.new { |user| user.signup_step <= 2 }</tt>).
# The method, proc or string should return or evaluate to a true or false value.
#
def validates_presence_of(*attr_names)
configuration = { :on => :save }

View file

@ -202,6 +202,8 @@ module ActiveResource
# sets the <tt>read_timeout</tt> of the internal Net::HTTP instance to the same value. The default
# <tt>read_timeout</tt> is 60 seconds on most Ruby implementations.
class Base
##
# :singleton-method:
# The logger for diagnosing and tracing Active Resource calls.
cattr_accessor :logger

View file

@ -13,6 +13,8 @@ module ActiveSupport
MAX_BUFFER_SIZE = 1000
##
# :singleton-method:
# Set to false to disable the silencer
cattr_accessor :silencer
self.silencer = true

View file

@ -30,6 +30,8 @@ require 'logger'
#
# Note: This logger is deprecated in favor of ActiveSupport::BufferedLogger
class Logger
##
# :singleton-method:
# Set to false to disable the silencer
cattr_accessor :silencer
self.silencer = true

View file

@ -254,7 +254,7 @@ module ActiveSupport
# @person = Person.find(1)
# # => #<Person id: 1, name: "Donald E. Knuth">
#
# <%= link_to(@person.name, person_path %>
# <%= link_to(@person.name, person_path(@person)) %>
# # => <a href="/person/1-donald-e-knuth">Donald E. Knuth</a>
def parameterize(string, sep = '-')
re_sep = Regexp.escape(sep)

View file

@ -282,6 +282,7 @@ task :guides do
FileUtils.mkdir(html)
template = File.expand_path("doc/guides/source/templates/guides.html.erb")
asciidoc_conf = 'doc/guides/asciidoc.conf'
ignore = ['..', 'icons', 'images', 'templates', 'stylesheets']
ignore << 'active_record_basics.txt'
@ -311,7 +312,7 @@ task :guides do
begin
puts "GENERATING => #{output}"
ENV['MANUALSONRAILS_TOC'] = 'no' if indexless.include?(entry)
Mizuho::Generator.new(input, :output => output, :template => template).start
Mizuho::Generator.new(input, :output => output, :template => template, :conf_file => asciidoc_conf).start
rescue Mizuho::GenerationError
STDERR.puts "*** ERROR"
exit 2

View file

@ -0,0 +1,26 @@
# Asciidoc substitutes some characters by default, those are called
# "replacements" in the docs. For example => becomes a unicode arrow.
#
# We override replacements to allow copy & paste of source code.
[replacements]
# Ellipsis
(?<!\\)\.\.\.=...
\\\.\.\.=...
# -> right arrow
(?<!\\)-&gt;==-&gt;
\\-&gt;=-&gt;
# => right double arrow
(?<!\\)\=&gt;==&gt;
\\\=&gt;==&gt;
# <- left arrow
(?<!\\)&lt;-=&lt;-
\\&lt;-=&lt;-
# <= left double arrow
(?<!\\)&lt;\==&lt;=
\\&lt;\==&lt;=

View file

@ -789,7 +789,7 @@ You can now easily <a href="http://m.onkey.org/2008/7/20/rescue-from-dispatching
</li>
<li>
<p>
The HTTP Accept header is disabled by default now. You should prefer the use of formatted URLs (such as <tt>/customers/1.xml</tt>) to indicate the format that you want. If you need the Accept headers, you can turn them back on with <tt>config.action_controller.user_accept_header = true</tt>.
The HTTP Accept header is disabled by default now. You should prefer the use of formatted URLs (such as <tt>/customers/1.xml</tt>) to indicate the format that you want. If you need the Accept headers, you can turn them back on with <tt>config.action_controller.use_accept_header = true</tt>.
</p>
</li>
<li>
@ -974,7 +974,7 @@ The addition of <tt>ActiveSupport::Rescuable</tt> allows any class to mix in the
</li>
<li>
<p>
<tt>Array#second</tt> through <tt>Array#tenth</tt> as aliases for <tt>Array#[1]</tt> through <tt>Array#[9]</tt>
<tt>Array#second</tt> through <tt>Array#fifth</tt> as aliases for <tt>Array#[1]</tt> through <tt>Array#[4]</tt>
</p>
</li>
<li>
@ -994,7 +994,7 @@ The addition of <tt>ActiveSupport::Rescuable</tt> allows any class to mix in the
</li>
<li>
<p>
The included TzInfo library has been upgraded to version 0.3.11.
The included TzInfo library has been upgraded to version 0.3.12.
</p>
</li>
<li>
@ -1017,7 +1017,7 @@ The included TzInfo library has been upgraded to version 0.3.11.
</li>
<li>
<p>
<tt>rake gems</tt> to list all configured gems, as well as whether they (and their dependencies) are installed or frozen
<tt>rake gems</tt> to list all configured gems, as well as whether they (and their dependencies) are installed, frozen, or framework (framework gems are those loaded by Rails before the gem dependency code is executed; such gems cannot be frozen)
</p>
</li>
<li>
@ -1068,6 +1068,11 @@ More information:
<a href="http://afreshcup.com/2008/10/25/rails-212-and-22rc1-update-your-rubygems/">Rails 2.1.2 and 2.2RC1: Update Your RubyGems</a>
</p>
</li>
<li>
<p>
<a href="http://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/1128">Detailed discussion on Lighthouse</a>
</p>
</li>
</ul></div>
</li>
</ul></div>

View file

@ -723,7 +723,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>Note that while for session values, you set the key to <tt>nil</tt>, to delete a cookie value, you should use <tt>cookies.delete(:key)</tt>.</p></div>
<div class="para"><p>Note that while for session values you set the key to <tt>nil</tt>, to delete a cookie value you should use <tt>cookies.delete(:key)</tt>.</p></div>
</div>
<h2 id="_filters">6. Filters</h2>
<div class="sectionbody">
@ -767,7 +767,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>In this example, the filter is added to ApplicationController and thus all controllers in the application. This will make everything in the application require the user to be logged in in order to use it. For obvious reasons (the user wouldn't be able to log in in the first place!), not all controllers or actions should require this. You can prevent this filter from running before particular actions with <tt>skip_before_filter</tt> :</p></div>
<div class="para"><p>In this example, the filter is added to ApplicationController and thus all controllers in the application. This will make everything in the application require the user to be logged in in order to use it. For obvious reasons (the user wouldn't be able to log in in the first place!), not all controllers or actions should require this. You can prevent this filter from running before particular actions with <tt>skip_before_filter</tt>:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -779,7 +779,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>Now, the <tt>LoginsController</tt>'s "new" and "create" actions will work as before without requiring the user to be logged in. The <tt>:only</tt> option is used to only skip this filter for these actions, and there is also an <tt>:except</tt> option which works the other way. These options can be used when adding filters too, so you can add a filter which only runs for selected actions in the first place.</p></div>
<div class="para"><p>Now, the LoginsController's <tt>new</tt> and <tt>create</tt> actions will work as before without requiring the user to be logged in. The <tt>:only</tt> option is used to only skip this filter for these actions, and there is also an <tt>:except</tt> option which works the other way. These options can be used when adding filters too, so you can add a filter which only runs for selected actions in the first place.</p></div>
<h3 id="_after_filters_and_around_filters">6.1. After Filters and Around Filters</h3>
<div class="para"><p>In addition to the before filters, you can run filters after an action has run or both before and after. The after filter is similar to the before filter, but because the action has already been run it has access to the response data that's about to be sent to the client. Obviously, after filters can not stop the action from running. Around filters are responsible for running the action, but they can choose not to, which is the around filter's way of stopping it.</p></div>
<div class="listingblock">
@ -872,7 +872,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>Now the <tt>create</tt> action won't run unless the "username" and "password" parameters are present, and if they're not, an error message will be added to the flash and the "new" action will be rendered. But there's something rather important missing from the verification above: It will be used for <strong>every</strong> action in LoginsController, which is not what we want. You can limit which actions it will be used for with the <tt>:only</tt> and <tt>:except</tt> options just like a filter:</p></div>
<div class="para"><p>Now the <tt>create</tt> action won't run unless the "username" and "password" parameters are present, and if they're not, an error message will be added to the flash and the <tt>new</tt> action will be rendered. But there's something rather important missing from the verification above: It will be used for <strong>every</strong> action in LoginsController, which is not what we want. You can limit which actions it will be used for with the <tt>:only</tt> and <tt>:except</tt> options just like a filter:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -934,7 +934,7 @@ host - The hostname used for this request.
</li>
<li>
<p>
domain - The hostname without the first segment (usually "www").
domain(n=2) - The hostname's first <tt>n</tt> segments, starting from the right (the TLD)
</p>
</li>
<li>
@ -949,7 +949,7 @@ method - The HTTP method used for the request.
</li>
<li>
<p>
get?, post?, put?, delete?, head? - Returns true if the HTTP method is get/post/put/delete/head.
get?, post?, put?, delete?, head? - Returns true if the HTTP method is GET/POST/PUT/DELETE/HEAD.
</p>
</li>
<li>
@ -964,7 +964,7 @@ port - The port number (integer) used for the request.
</li>
<li>
<p>
protocol - The protocol used for the request.
protocol - Returns a string containing the prototol used plus "://", for example "http://"
</p>
</li>
<li>
@ -1118,7 +1118,7 @@ http://www.gnu.org/software/src-highlite -->
<td class="icon">
<img src="./images/icons/tip.png" alt="Tip" />
</td>
<td class="content">It is not recommended that you stream static files through Rails if you can instead keep them in a public folder on your web server. It is much more efficient to let the user download the file directly using Apache or another web server, keeping the request from unnecessarily going through the whole Rails stack.</td>
<td class="content">It is not recommended that you stream static files through Rails if you can instead keep them in a public folder on your web server. It is much more efficient to let the user download the file directly using Apache or another web server, keeping the request from unnecessarily going through the whole Rails stack. Although if you do need the request to go through Rails for some reason, you can set the <tt>:x_sendfile</tt> option to true, and Rails will let the web server handle sending the file to the user, freeing up the Rails process to do other things. Note that your web server needs to support the <tt>X-Sendfile</tt> header for this to work, and you still have to be careful not to use user input in a way that lets someone retrieve arbitrary files.</td>
</tr></table>
</div>
<h3 id="_restful_downloads">11.2. RESTful Downloads</h3>
@ -1166,7 +1166,7 @@ http://www.gnu.org/software/src-highlite -->
</div>
<h2 id="_parameter_filtering">12. Parameter Filtering</h2>
<div class="sectionbody">
<div class="para"><p>Rails keeps a log file for each environment (development, test and production) in the "log" folder. These are extremely useful when debugging what's actually going on in your application, but in a live application you may not want every bit of information to be stored in the log file. The <tt>filter_parameter_logging</tt> method can be used to filter out sensitive information from the log. It works by replacing certain values in the <tt>params</tt> hash with "[FILTERED]" as they are written to the log. As an example, let's see how to filter all parameters with keys that include "password":</p></div>
<div class="para"><p>Rails keeps a log file for each environment (development, test and production) in the <tt>log</tt> folder. These are extremely useful when debugging what's actually going on in your application, but in a live application you may not want every bit of information to be stored in the log file. The <tt>filter_parameter_logging</tt> method can be used to filter out sensitive information from the log. It works by replacing certain values in the <tt>params</tt> hash with "[FILTERED]" as they are written to the log. As an example, let's see how to filter all parameters with keys that include "password":</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -1178,7 +1178,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>The method works recursively through all levels of the params hash and takes an optional second parameter which is used as the replacement string if present. It can also take a block which receives each key in return and replaces those for which the block returns true.</p></div>
<div class="para"><p>The method works recursively through all levels of the params hash and takes an optional second parameter which is used as the replacement string if present. It can also take a block which receives each key in turn and replaces those for which the block returns true.</p></div>
</div>
<h2 id="_rescue">13. Rescue</h2>
<div class="sectionbody">

View file

@ -267,6 +267,53 @@ ul#navMain {
<a href="#_writing_your_own_validation_methods">Writing your own validation methods</a>
</li>
<li>
<a href="#_using_the_tt_errors_tt_collection">Using the <tt>errors</tt> collection</a>
</li>
<li>
<a href="#_callbacks">Callbacks</a>
<ul>
<li><a href="#_callbacks_registration">Callbacks registration</a></li>
<li><a href="#_registering_callbacks_by_overriding_the_callback_methods">Registering callbacks by overriding the callback methods</a></li>
<li><a href="#_registering_callbacks_by_using_macro_style_class_methods">Registering callbacks by using macro-style class methods</a></li>
</ul>
</li>
<li>
<a href="#_available_callbacks">Available callbacks</a>
<ul>
<li><a href="#_callbacks_called_both_when_creating_or_updating_a_record">Callbacks called both when creating or updating a record.</a></li>
<li><a href="#_callbacks_called_only_when_creating_a_new_record">Callbacks called only when creating a new record.</a></li>
<li><a href="#_callbacks_called_only_when_updating_an_existing_record">Callbacks called only when updating an existing record.</a></li>
<li><a href="#_callbacks_called_when_removing_a_record_from_the_database">Callbacks called when removing a record from the database.</a></li>
<li><a href="#_the_tt_after_initialize_tt_and_tt_after_find_tt_callbacks">The <tt>after_initialize</tt> and <tt>after_find</tt> callbacks</a></li>
</ul>
</li>
<li>
<a href="#_halting_execution">Halting Execution</a>
</li>
<li>
<a href="#_callback_classes">Callback classes</a>
</li>
<li>
<a href="#_observers">Observers</a>
<ul>
<li><a href="#_registering_observers">Registering observers</a></li>
<li><a href="#_where_to_put_the_observers_source_files">Where to put the observers' source files</a></li>
</ul>
</li>
<li>
<a href="#_changelog">Changelog</a>
</li>
</ol>
@ -358,7 +405,15 @@ http://www.gnu.org/software/src-highlite -->
&gt;&gt; p.new_record?
=&gt; false</tt></pre>
</div></div>
<div class="para"><p>Saving new records means sending an SQL insert operation to the database, while saving existing records (by calling either <tt>save</tt>, <tt>update_attribute</tt> or <tt>update_attributes</tt>) will result in a SQL update operation. Active Record will use this facts to perform validations upon your objects, avoiding then to be recorded to the database if their inner state is invalid in some way. You can specify validations that will be beformed every time a object is saved, just when you're creating a new record or when you're updating an existing one.</p></div>
<div class="para"><p>Saving new records means sending an SQL insert operation to the database, while saving existing records (by calling either <tt>save</tt> or <tt>update_attributes</tt>) will result in a SQL update operation. Active Record will use this facts to perform validations upon your objects, avoiding then to be recorded to the database if their inner state is invalid in some way. You can specify validations that will be beformed every time a object is saved, just when you're creating a new record or when you're updating an existing one.</p></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<img src="./images/icons/caution.png" alt="Caution" />
</td>
<td class="content">There are four methods that when called will trigger validation: <tt>save</tt>, <tt>save!</tt>, <tt>update_attributes</tt> and <tt>update_attributes!</tt>. There is one method left, which is <tt>update_attribute</tt>. This method will update the value of an attribute without triggering any validation, so be careful when using <tt>update_attribute</tt>, since it can let you save your objects in an invalid state.</td>
</tr></table>
</div>
<h3 id="_the_meaning_of_em_valid_em">2.2. The meaning of <em>valid</em></h3>
<div class="para"><p>For verifying if an object is valid, Active Record uses the <tt>valid?</tt> method, which basically looks inside the object to see if it has any validation errors. These errors live in a collection that can be accessed through the <tt>errors</tt> instance method. The proccess is really simple: If the <tt>errors</tt> method returns an empty collection, the object is valid and can be saved. Each time a validation fails, an error message is added to the <tt>errors</tt> collection.</p></div>
</div>
@ -719,7 +774,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>If your validation rules are too complicated and you want to break it in small methods, you can implement all of them and call one of <tt>validate</tt>, <tt>validate_on_create</tt> or <tt>validate_on_update</tt> methods, passing it the symbols for the methods' names.</p></div>
<div class="para"><p>If your validation rules are too complicated and you want to break them in small methods, you can implement all of them and call one of <tt>validate</tt>, <tt>validate_on_create</tt> or <tt>validate_on_update</tt> methods, passing it the symbols for the methods' names.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -738,7 +793,400 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
</div>
<h2 id="_changelog">7. Changelog</h2>
<h2 id="_using_the_tt_errors_tt_collection">7. Using the <tt>errors</tt> collection</h2>
<div class="sectionbody">
<div class="para"><p>You can do more than just call <tt>valid?</tt> upon your objects based on the existance of the <tt>errors</tt> collection. Here is a list of the other available methods that you can use to manipulate errors or ask for an object's state.</p></div>
<div class="ilist"><ul>
<li>
<p>
<tt>add_to_base</tt> lets you add errors messages that are related to the object's state as a whole, instead of being related to a specific attribute. You can use this method when you want to say that the object is invalid, no matter the values of it's attributes. <tt>add_to_base</tt> receives a string with the message.
</p>
</li>
</ul></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Person <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> a_method_used_for_validation_purposes
errors<span style="color: #990000">.</span>add_to_base<span style="color: #990000">(</span><span style="color: #FF0000">"This person is invalid because ..."</span><span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="ilist"><ul>
<li>
<p>
<tt>add</tt> lets you manually add messages that are related to particular attributes. When writing those messages, keep in mind that Rails will prepend them with the name of the attribute that holds the error, so write it in a way that makes sense. <tt>add</tt> receives a symbol with the name of the attribute that you want to add the message to and the message itself.
</p>
</li>
</ul></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Person <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> a_method_used_for_validation_purposes
errors<span style="color: #990000">.</span>add<span style="color: #990000">(:</span>name<span style="color: #990000">,</span> <span style="color: #FF0000">"can't have the characters !@#$%*()_-+="</span><span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="ilist"><ul>
<li>
<p>
<tt>invalid?</tt> is used when you want to check if a particular attribute is invalid. It receives a symbol with the name of the attribute that you want to check.
</p>
</li>
</ul></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Person <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
validates_presence_of <span style="color: #990000">:</span>name<span style="color: #990000">,</span> <span style="color: #990000">:</span>email
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new<span style="color: #990000">(:</span>name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"John Doe"</span><span style="color: #990000">)</span>
person<span style="color: #990000">.</span>invalid?<span style="color: #990000">(:</span>email<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; true</span></span>
</tt></pre></div></div>
<div class="ilist"><ul>
<li>
<p>
<tt>on</tt> is used when you want to check the error messages for a specific attribute. It will return different kinds of objects depending on the state of the <tt>errors</tt> collection for the given attribute. If there are no errors related to the attribute, <tt>on</tt> will return <tt>nil</tt>. If there is just one errors message for this attribute, <tt>on</tt> will return a string with the message. When <tt>errors</tt> holds two or more error messages for the attribute, <tt>on</tt> will return an array of strings, each one with one error message.
</p>
</li>
</ul></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Person <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
validates_presence_of <span style="color: #990000">:</span>name
validates_length_of <span style="color: #990000">:</span>name<span style="color: #990000">,</span> <span style="color: #990000">:</span>minimum <span style="color: #990000">=&gt;</span> <span style="color: #993399">3</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new<span style="color: #990000">(:</span>name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"John Doe"</span><span style="color: #990000">)</span>
person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; true</span></span>
person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; nil</span></span>
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new<span style="color: #990000">(:</span>name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"JD"</span><span style="color: #990000">)</span>
person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; "is too short (minimum is 3 characters)"</span></span>
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new
person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; ["can't be blank", "is too short (minimum is 3 characters)"]</span></span>
</tt></pre></div></div>
<div class="ilist"><ul>
<li>
<p>
<tt>clear</tt> is used when you intentionally wants to clear all the messages in the <tt>errors</tt> collection.
</p>
</li>
</ul></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Person <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
validates_presence_of <span style="color: #990000">:</span>name
validates_length_of <span style="color: #990000">:</span>name<span style="color: #990000">,</span> <span style="color: #990000">:</span>minimum <span style="color: #990000">=&gt;</span> <span style="color: #993399">3</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new
puts person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; ["can't be blank", "is too short (minimum is 3 characters)"]</span></span>
person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>clear
person<span style="color: #990000">.</span>errors <span style="font-style: italic"><span style="color: #9A1900"># =&gt; nil</span></span>
</tt></pre></div></div>
</div>
<h2 id="_callbacks">8. Callbacks</h2>
<div class="sectionbody">
<div class="para"><p>Callbacks are methods that get called at certain moments of an object's lifecycle. With callbacks it's possible to write code that will run whenever an Active Record object is created, saved, updated, deleted or loaded from the database.</p></div>
<h3 id="_callbacks_registration">8.1. Callbacks registration</h3>
<div class="para"><p>In order to use the available callbacks, you need to registrate them. There are two ways of doing that.</p></div>
<h3 id="_registering_callbacks_by_overriding_the_callback_methods">8.2. Registering callbacks by overriding the callback methods</h3>
<div class="para"><p>You can specify the callback method direcly, by overriding it. Let's see how it works using the <tt>before_validation</tt> callback, which will surprisingly run right before any validation is done.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> User <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
validates_presence_of <span style="color: #990000">:</span>login<span style="color: #990000">,</span> <span style="color: #990000">:</span>email
protected
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> before_validation
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="font-weight: bold"><span style="color: #0000FF">self</span></span><span style="color: #990000">.</span>login<span style="color: #990000">.</span><span style="font-weight: bold"><span style="color: #0000FF">nil</span></span><span style="color: #990000">?</span>
<span style="font-weight: bold"><span style="color: #0000FF">self</span></span><span style="color: #990000">.</span>login <span style="color: #990000">=</span> email <span style="font-weight: bold"><span style="color: #0000FF">unless</span></span> email<span style="color: #990000">.</span>blank?
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<h3 id="_registering_callbacks_by_using_macro_style_class_methods">8.3. Registering callbacks by using macro-style class methods</h3>
<div class="para"><p>The other way you can register a callback method is by implementing it as an ordinary method, and then using a macro-style class method to register it as a callback. The last example could be written like that:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> User <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
validates_presence_of <span style="color: #990000">:</span>login<span style="color: #990000">,</span> <span style="color: #990000">:</span>email
before_validation <span style="color: #990000">:</span>ensure_login_has_a_value
protected
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> ensure_login_has_a_value
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="font-weight: bold"><span style="color: #0000FF">self</span></span><span style="color: #990000">.</span>login<span style="color: #990000">.</span><span style="font-weight: bold"><span style="color: #0000FF">nil</span></span><span style="color: #990000">?</span>
<span style="font-weight: bold"><span style="color: #0000FF">self</span></span><span style="color: #990000">.</span>login <span style="color: #990000">=</span> email <span style="font-weight: bold"><span style="color: #0000FF">unless</span></span> email<span style="color: #990000">.</span>blank?
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>The macro-style class methods can also receive a block. Rails best practices say that you should only use this style of registration if the code inside your block is so short that it fits in just one line.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> User <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
validates_presence_of <span style="color: #990000">:</span>login<span style="color: #990000">,</span> <span style="color: #990000">:</span>email
before_create <span style="color: #FF0000">{</span><span style="color: #990000">|</span>user<span style="color: #990000">|</span> user<span style="color: #990000">.</span>name <span style="color: #990000">=</span> user<span style="color: #990000">.</span>login<span style="color: #990000">.</span>capitalize <span style="font-weight: bold"><span style="color: #0000FF">if</span></span> user<span style="color: #990000">.</span>name<span style="color: #990000">.</span>blank?<span style="color: #FF0000">}</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>In Rails, the preferred way of registering callbacks is by using macro-style class methods. The main advantages of using macro-style class methods are:</p></div>
<div class="ilist"><ul>
<li>
<p>
You can add more than one method for each type of callback. Those methods will be queued for execution at the same order they were registered.
</p>
</li>
<li>
<p>
Readability, since your callback declarations will live at the beggining of your models' files.
</p>
</li>
</ul></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<img src="./images/icons/caution.png" alt="Caution" />
</td>
<td class="content">Remember to always declare the callback methods as being protected or private. These methods should never be public, otherwise it will be possible to call them from code outside the model, violating object encapsulation and exposing implementation details.</td>
</tr></table>
</div>
</div>
<h2 id="_available_callbacks">9. Available callbacks</h2>
<div class="sectionbody">
<div class="para"><p>Here is a list with all the available Active Record callbacks, listed in the same order in which they will get called during the respective operations.</p></div>
<h3 id="_callbacks_called_both_when_creating_or_updating_a_record">9.1. Callbacks called both when creating or updating a record.</h3>
<div class="ilist"><ul>
<li>
<p>
<tt>before_validation</tt>
</p>
</li>
<li>
<p>
<tt>after_validation</tt>
</p>
</li>
<li>
<p>
<tt>before_save</tt>
</p>
</li>
<li>
<p>
<strong>INSERT OR UPDATE OPERATION</strong>
</p>
</li>
<li>
<p>
<tt>after_save</tt>
</p>
</li>
</ul></div>
<h3 id="_callbacks_called_only_when_creating_a_new_record">9.2. Callbacks called only when creating a new record.</h3>
<div class="ilist"><ul>
<li>
<p>
<tt>before_validation_on_create</tt>
</p>
</li>
<li>
<p>
<tt>after_validation_on_create</tt>
</p>
</li>
<li>
<p>
<tt>before_create</tt>
</p>
</li>
<li>
<p>
<strong>INSERT OPERATION</strong>
</p>
</li>
<li>
<p>
<tt>after_create</tt>
</p>
</li>
</ul></div>
<h3 id="_callbacks_called_only_when_updating_an_existing_record">9.3. Callbacks called only when updating an existing record.</h3>
<div class="ilist"><ul>
<li>
<p>
<tt>before_validation_on_update</tt>
</p>
</li>
<li>
<p>
<tt>after_validation_on_update</tt>
</p>
</li>
<li>
<p>
<tt>before_update</tt>
</p>
</li>
<li>
<p>
<strong>UPDATE OPERATION</strong>
</p>
</li>
<li>
<p>
<tt>after_update</tt>
</p>
</li>
</ul></div>
<h3 id="_callbacks_called_when_removing_a_record_from_the_database">9.4. Callbacks called when removing a record from the database.</h3>
<div class="ilist"><ul>
<li>
<p>
<tt>before_destroy</tt>
</p>
</li>
<li>
<p>
<strong>DELETE OPERATION</strong>
</p>
</li>
<li>
<p>
<tt>after_destroy</tt>
</p>
</li>
</ul></div>
<div class="para"><p>The <tt>before_destroy</tt> and <tt>after_destroy</tt> callbacks will only be called if you delete the model using either the <tt>destroy</tt> instance method or one of the <tt>destroy</tt> or <tt>destroy_all</tt> class methods of your Active Record class. If you use <tt>delete</tt> or <tt>delete_all</tt> no callback operations will run, since Active Record will not instantiate any objects, accessing the records to be deleted directly in the database.</p></div>
<h3 id="_the_tt_after_initialize_tt_and_tt_after_find_tt_callbacks">9.5. The <tt>after_initialize</tt> and <tt>after_find</tt> callbacks</h3>
<div class="para"><p>The <tt>after_initialize</tt> callback will be called whenever an Active Record object is instantiated, either by direcly using <tt>new</tt> or when a record is loaded from the database. It can be useful to avoid the need to directly override your Active Record <tt>initialize</tt> method.</p></div>
<div class="para"><p>The <tt>after_find</tt> callback will be called whenever Active Record loads a record from the database. When used together with <tt>after_initialize</tt> it will run first, since Active Record will first read the record from the database and them create the model object that will hold it.</p></div>
<div class="para"><p>The <tt>after_initialize</tt> and <tt>after_find</tt> callbacks are a bit different from the others, since the only way to register those callbacks is by defining them as methods. If you try to register <tt>after_initialize</tt> or <tt>after_find</tt> using macro-style class methods, they will just be ignored. This behaviour is due to performance reasons, since <tt>after_initialize</tt> and <tt>after_find</tt> will both be called for each record found in the database, significantly slowing down the queries.</p></div>
</div>
<h2 id="_halting_execution">10. Halting Execution</h2>
<div class="sectionbody">
<div class="para"><p>As you start registering new callbacks for your models, they will be queued for execution. This queue will include all your model's validations, the registered callbacks and the database operation to be executed. However, if at any moment one of the callback methods returns a boolean <tt>false</tt> (not <tt>nil</tt>) value, this execution chain will be halted and the desired operation will not complete: your model will not get persisted in the database, or your records will not get deleted and so on.</p></div>
</div>
<h2 id="_callback_classes">11. Callback classes</h2>
<div class="sectionbody">
<div class="para"><p>Sometimes the callback methods that you'll write will be useful enough to be reused at other models. Active Record makes it possible to create classes that encapsulate the callback methods, so it becomes very easy to reuse them.</p></div>
<div class="para"><p>Here's an example where we create a class with a after_destroy callback for a PictureFile model.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> PictureFileCallbacks
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> after_destroy<span style="color: #990000">(</span>picture_file<span style="color: #990000">)</span>
File<span style="color: #990000">.</span>delete<span style="color: #990000">(</span>picture_file<span style="color: #990000">.</span>filepath<span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">if</span></span> File<span style="color: #990000">.</span>exists?<span style="color: #990000">(</span>picture_file<span style="color: #990000">.</span>filepath<span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>When declared inside a class the callback method will receive the model object as a parameter. We can now use it this way:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> PictureFile <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
after_destroy PictureFileCallbacks<span style="color: #990000">.</span>new
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>Note that we needed to instantiate a new PictureFileCallbacks object, since we declared our callback as an instance method. Sometimes it will make more sense to have it as a class method.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> PictureFileCallbacks
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> <span style="font-weight: bold"><span style="color: #0000FF">self</span></span><span style="color: #990000">.</span>after_destroy<span style="color: #990000">(</span>picture_file<span style="color: #990000">)</span>
File<span style="color: #990000">.</span>delete<span style="color: #990000">(</span>picture_file<span style="color: #990000">.</span>filepath<span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">if</span></span> File<span style="color: #990000">.</span>exists?<span style="color: #990000">(</span>picture_file<span style="color: #990000">.</span>filepath<span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>If the callback method is declared this way, it won't be necessary to instantiate a PictureFileCallbacks object.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> PictureFile <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
after_destroy PictureFileCallbacks
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>You can declare as many callbacks as you want inside your callback classes.</p></div>
</div>
<h2 id="_observers">12. Observers</h2>
<div class="sectionbody">
<div class="para"><p>Active Record callbacks are a powerful feature, but they can pollute your model implementation with code that's not directly related to the model's purpose. In object-oriented software, it's always a good idea to design your classes with a single responsability in the whole system. For example, it wouldn't make much sense to have a <tt>User</tt> model with a method that writes data about a login attempt to a log file. Whenever you're using callbacks to write code that's not directly related to your model class purposes, it may be a good moment to create an Observer.</p></div>
<div class="para"><p>An Active Record Observer is an object that links itself to a model and register it's methods for callbacks. Your model's implementation remain clean, while you can reuse the code in the Observer to add behaviuor to more than one model class. Ok, you may say that we can also do that using callback classes, but it would still force us to add code to our model's implementation.</p></div>
<div class="para"><p>Observer classes are subclasses of the <tt>ActiveRecord::Observer</tt> class. When this class is subclassed, Active Record will look at the name of the new class and then strip the <em>Observer</em> part to find the name of the Active Record class to observe.</p></div>
<div class="para"><p>Consider a <tt>Registration</tt> model, where we want to send an email everytime a new registration is created. Since sending emails is not directly related to our model's purpose, we could create an Observer to do just that:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> RegistrationObserver <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Observer
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> after_create<span style="color: #990000">(</span>model<span style="color: #990000">)</span>
<span style="font-style: italic"><span style="color: #9A1900"># code to send registration confirmation emails...</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>Like in callback classes, the observer's methods receive the observed model as a parameter.</p></div>
<div class="para"><p>Sometimes using the ModelName + Observer naming convention won't be the best choice, mainly when you want to use the same observer for more than one model class. It's possible to explicity specify the models that our observer should observe.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Auditor <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Observer
observe User<span style="color: #990000">,</span> Registration<span style="color: #990000">,</span> Invoice
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<h3 id="_registering_observers">12.1. Registering observers</h3>
<div class="para"><p>If you payed attention, you may be wondering where Active Record Observers are referenced in our applications, so they get instantiate and begin to interact with our models. For observers to work we need to register then in our application's <strong>config/environment.rb</strong> file. In this file there is a commented out line where we can define the observers that our application should load at start-up.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-style: italic"><span style="color: #9A1900"># Activate observers that should always be running</span></span>
config<span style="color: #990000">.</span>active_record<span style="color: #990000">.</span>observers <span style="color: #990000">=</span> <span style="color: #990000">:</span>registration_observer<span style="color: #990000">,</span> <span style="color: #990000">:</span>auditor
</tt></pre></div></div>
<h3 id="_where_to_put_the_observers_source_files">12.2. Where to put the observers' source files</h3>
<div class="para"><p>By convention, you should always save your observers' source files inside <strong>app/models</strong>.</p></div>
</div>
<h2 id="_changelog">13. Changelog</h2>
<div class="sectionbody">
<div class="para"><p><a href="http://rails.lighthouseapp.com/projects/16213/tickets/26-active-record-validations-and-callbacks">http://rails.lighthouseapp.com/projects/16213/tickets/26-active-record-validations-and-callbacks</a></p></div>
</div>

View file

@ -687,8 +687,8 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Employee <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
has_many <span style="color: #990000">:</span>subordinates<span style="color: #990000">,</span> <span style="color: #990000">:</span>class_name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"User"</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>foreign_key <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"manager_id"</span>
belongs_to <span style="color: #990000">:</span>manager<span style="color: #990000">,</span> <span style="color: #990000">:</span>class_name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"User"</span>
has_many <span style="color: #990000">:</span>subordinates<span style="color: #990000">,</span> <span style="color: #990000">:</span>class_name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Employee"</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>foreign_key <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"manager_id"</span>
belongs_to <span style="color: #990000">:</span>manager<span style="color: #990000">,</span> <span style="color: #990000">:</span>class_name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Employee"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>With this setup, you can retrieve <tt>@employee.subordinates</tt> and <tt>@employee.manager</tt>.</p></div>
@ -742,7 +742,9 @@ customer<span style="color: #990000">.</span>orders<span style="color: #990000">
<h3 id="_avoiding_name_collisions">3.2. Avoiding Name Collisions</h3>
<div class="para"><p>You are not free to use just any name for your associations. Because creating an association adds a method with that name to the model, it is a bad idea to give an association a name that is already used for an instance method of <tt>ActiveRecord::Base</tt>. The association method would override the base method and break things. For instance, <tt>attributes</tt> or <tt>connection</tt> are bad names for associations.</p></div>
<h3 id="_updating_the_schema">3.3. Updating the Schema</h3>
<div class="para"><p>Associations are extremely useful, but they are not magic. You are responsible for maintaining your database schema to match your associations. In practice, this means two things. First, you need to create foreign keys as appropriate:</p></div>
<div class="para"><p>Associations are extremely useful, but they are not magic. You are responsible for maintaining your database schema to match your associations. In practice, this means two things, depending on what sort of associations you are creating. For <tt>belongs_to</tt> associations you need to create foreign keys, and for <tt>has_and_belongs_to_many</tt> associations you need to create the appropriate join table.</p></div>
<h4 id="_creating_foreign_keys_for_tt_belongs_to_tt_associations">3.3.1. Creating Foreign Keys for <tt>belongs_to</tt> Associations</h4>
<div class="para"><p>When you declare a <tt>belongs_to</tt> association, you need to create foreign keys as appropriate. For example, consider this model:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -761,9 +763,9 @@ http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> CreateOrders <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Migration
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> <span style="font-weight: bold"><span style="color: #0000FF">self</span></span><span style="color: #990000">.</span>up
create_table <span style="color: #990000">:</span>orders <span style="font-weight: bold"><span style="color: #0000FF">do</span></span> <span style="color: #990000">|</span>t<span style="color: #990000">|</span>
t<span style="color: #990000">.</span>order_date <span style="color: #990000">:</span>datetime
t<span style="color: #990000">.</span>order_number <span style="color: #990000">:</span>string
t<span style="color: #990000">.</span>customer_id <span style="color: #990000">:</span>integer
t<span style="color: #990000">.</span>datetime <span style="color: #990000">:</span>order_date
t<span style="color: #990000">.</span>string <span style="color: #990000">:</span>order_number
t<span style="color: #990000">.</span>integer <span style="color: #990000">:</span>customer_id
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
@ -773,7 +775,8 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>If you create an association some time after you build the underlying model, you need to remember to create an <tt>add_column</tt> migration to provide the necessary foreign key.</p></div>
<div class="para"><p>Second, if you create a <tt>has_and_belongs_to_many</tt> association, you need to explicitly create the joining table. Unless the name of the join table is explicitly specified by using the <tt>:join_table</tt> option, Active Record create the name by using the lexical order of the class names. So a join between customer and order models will give the default join table name of "customers_orders" because "c" outranks "o" in lexical ordering.</p></div>
<h4 id="_creating_join_tables_for_tt_has_and_belongs_to_many_tt_associations">3.3.2. Creating Join Tables for <tt>has_and_belongs_to_many</tt> Associations</h4>
<div class="para"><p>If you create a <tt>has_and_belongs_to_many</tt> association, you need to explicitly create the joining table. Unless the name of the join table is explicitly specified by using the <tt>:join_table</tt> option, Active Record create the name by using the lexical order of the class names. So a join between customer and order models will give the default join table name of "customers_orders" because "c" outranks "o" in lexical ordering.</p></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
@ -1938,7 +1941,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<h5 id="_tt_offset_tt"><tt>:offset</tt></h5>
<div class="para"><p>The <tt>:offset</tt> option lets you specify the starting offset for fetching objects via an association. For example, if you set <tt>:offset &#8658; 11</tt>, it will skip the first 10 records.</p></div>
<div class="para"><p>The <tt>:offset</tt> option lets you specify the starting offset for fetching objects via an association. For example, if you set <tt>:offset &#8658; 11</tt>, it will skip the first 11 records.</p></div>
<h5 id="_tt_order_tt_2"><tt>:order</tt></h5>
<div class="para"><p>The <tt>:order</tt> option dictates the order in which associated objects will be received (in the syntax used by a SQL <tt>ORDER BY</tt> clause).</p></div>
<div class="listingblock">
@ -2409,7 +2412,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<h5 id="_tt_offset_tt_2"><tt>:offset</tt></h5>
<div class="para"><p>The <tt>:offset</tt> option lets you specify the starting offset for fetching objects via an association. For example, if you set <tt>:offset &#8658; 11</tt>, it will skip the first 10 records.</p></div>
<div class="para"><p>The <tt>:offset</tt> option lets you specify the starting offset for fetching objects via an association. For example, if you set <tt>:offset &#8658; 11</tt>, it will skip the first 11 records.</p></div>
<h5 id="_tt_order_tt_3"><tt>:order</tt></h5>
<div class="para"><p>The <tt>:order</tt> option dictates the order in which associated objects will be received (in the syntax used by a SQL <tt>ORDER BY</tt> clause).</p></div>
<div class="listingblock">

View file

@ -231,6 +231,11 @@ Heiko has rarely looked back.</p></div>
<div class="para"><p>Tore Darell is an independent developer based in Menton, France who specialises in cruft-free web applications using Ruby, Rails
and unobtrusive JavaScript. His home on the internet is his blog <a href="http://tore.darell.no/">Sneaky Abstractions</a>.</p></div>
</div></div>
<div class="sidebarblock" id="zilkey">
<div class="sidebar-content">
<div class="sidebar-title">Jeff Dean</div>
<div class="para"><p>Jeff Dean is a software engineer with <a href="http://pivotallabs.com/">Pivotal Labs</a>.</p></div>
</div></div>
</div>
</div>

View file

@ -217,6 +217,9 @@ ul#navMain {
</ul>
</li>
<li>
<a href="#_conditional_get_support">Conditional GET support</a>
</li>
<li>
<a href="#_advanced_caching">Advanced Caching</a>
</li>
</ol>
@ -235,8 +238,8 @@ need to return to those hungry web clients in the shortest time possible.</p></d
<div class="sectionbody">
<div class="para"><p>This is an introduction to the three types of caching techniques that Rails
provides by default without the use of any third party plugins.</p></div>
<div class="para"><p>To get started make sure config.action_controller.perform_caching is set
to true for your environment. This flag is normally set in the
<div class="para"><p>To get started make sure <tt>config.action_controller.perform_caching</tt> is set
to <tt>true</tt> for your environment. This flag is normally set in the
corresponding config/environments/*.rb and caching is disabled by default
there for development and test, and enabled for production.</p></div>
<div class="listingblock">
@ -270,19 +273,19 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>The first time anyone requests products/index, Rails will generate a file
called index.html and the webserver will then look for that file before it
called <tt>index.html</tt> and the webserver will then look for that file before it
passes the next request for products/index to your Rails application.</p></div>
<div class="para"><p>By default, the page cache directory is set to Rails.public_path (which is
usually set to RAILS_ROOT + "/public") and this can be configured by
changing the configuration setting ActionController::Base.page_cache_directory. Changing the
default from /public helps avoid naming conflicts, since you may want to
put other static html in /public, but changing this will require web
server reconfiguration to let the web server know where to serve the
cached files from.</p></div>
<div class="para"><p>The Page Caching mechanism will automatically add a .html exxtension to
usually set to <tt>RAILS_ROOT + "/public"</tt>) and this can be configured by
changing the configuration setting <tt>config.action_controller.page_cache_directory</tt>.
Changing the default from /public helps avoid naming conflicts, since you may
want to put other static html in /public, but changing this will require web
server reconfiguration to let the web server know where to serve the cached
files from.</p></div>
<div class="para"><p>The Page Caching mechanism will automatically add a <tt>.html</tt> exxtension to
requests for pages that do not have an extension to make it easy for the
webserver to find those pages and this can be configured by changing the
configuration setting ActionController::Base.page_cache_extension.</p></div>
configuration setting <tt>config.action_controller.page_cache_extension</tt>.</p></div>
<div class="para"><p>In order to expire this page when a new product is added we could extend our
example controler like this:</p></div>
<div class="listingblock">
@ -337,8 +340,8 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>And you can also use :if (or :unless) to pass a Proc that specifies when the
action should be cached. Also, you can use :layout &#8658; false to cache without
<div class="para"><p>And you can also use <tt>:if</tt> (or <tt>:unless</tt>) to pass a Proc that specifies when the
action should be cached. Also, you can use <tt>:layout &#8658; false</tt> to cache without
layout so that dynamic information in the layout such as logged in user info
or the number of items in the cart can be left uncached. This feature is
available as of Rails 2.2.</p></div>
@ -377,7 +380,7 @@ http://www.gnu.org/software/src-highlite -->
</tt></pre></div></div>
<div class="para"><p>The cache block in our example will bind to the action that called it and is
written out to the same place as the Action Cache, which means that if you
want to cache multiple fragments per action, you should provide an action_suffix to the cache call:</p></div>
want to cache multiple fragments per action, you should provide an <tt>action_suffix</tt> to the cache call:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -386,18 +389,38 @@ http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="color: #FF0000">&lt;% cache(:action =&gt;</span> <span style="color: #FF0000">'recent'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action_suffix <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'all_products'</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">do</span></span> <span style="color: #990000">%&gt;</span>
All available products<span style="color: #990000">:</span>
</tt></pre></div></div>
<div class="para"><p>and you can expire it using the expire_fragment method, like so:</p></div>
<div class="para"><p>and you can expire it using the <tt>expire_fragment</tt> method, like so:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>expire_fragment<span style="color: #990000">(:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'producst'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'recent'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action_suffix <span style="color: #990000">=&gt;</span> 'all_products<span style="color: #990000">)</span>
<pre><tt>expire_fragment<span style="color: #990000">(:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'products'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'recent'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action_suffix <span style="color: #990000">=&gt;</span> 'all_products<span style="color: #990000">)</span>
</tt></pre></div></div>
<div class="para"><p>If you don't want the cache block to bind to the action that called it, You can
also use globally keyed fragments by calling the cache method with a key, like
so:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="color: #FF0000">&lt;% cache(:key =&gt;</span> <span style="color: #990000">[</span><span style="color: #FF0000">'all_available_products'</span><span style="color: #990000">,</span> <span style="color: #009900">@latest_product</span><span style="color: #990000">.</span>created_at<span style="color: #990000">].</span>join<span style="color: #990000">(</span><span style="color: #FF0000">':'</span><span style="color: #990000">))</span> <span style="font-weight: bold"><span style="color: #0000FF">do</span></span> <span style="color: #990000">%&gt;</span>
All available products<span style="color: #990000">:</span>
</tt></pre></div></div>
<div class="para"><p>This fragment is then available to all actions in the ProductsController using
the key and can be expired the same way:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>expire_fragment<span style="color: #990000">(:</span>key <span style="color: #990000">=&gt;</span> <span style="color: #990000">[</span><span style="color: #FF0000">'all_available_products'</span><span style="color: #990000">,</span> <span style="color: #009900">@latest_product</span><span style="color: #990000">.</span>created_at<span style="color: #990000">].</span>join<span style="color: #990000">(</span><span style="color: #FF0000">':'</span><span style="color: #990000">))</span>
</tt></pre></div></div>
<h3 id="_sweepers">1.4. Sweepers</h3>
<div class="para"><p>Cache sweeping is a mechanism which allows you to get around having a ton of
expire_{page,action,fragment} calls in your code by moving all the work
required to expire cached content into a ActionController::Caching::Sweeper
required to expire cached content into a <tt>ActionController::Caching::Sweeper</tt>
class that is an Observer and looks for changes to an object via callbacks,
and when a change occurs it expires the caches associated with that object n
an around or after filter.</p></div>
@ -547,8 +570,7 @@ http://www.gnu.org/software/src-highlite -->
<pre><tt>ActionController<span style="color: #990000">::</span>Base<span style="color: #990000">.</span>cache_store <span style="color: #990000">=</span> <span style="color: #990000">:</span>drb_store<span style="color: #990000">,</span> <span style="color: #FF0000">"druby://localhost:9192"</span>
</tt></pre></div></div>
<div class="para"><p>4) MemCached store: Works like DRbStore, but uses Danga's MemCache instead.
Requires the ruby-memcache library:
gem install ruby-memcache.</p></div>
Rails uses the bundled memcached-client gem by default.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -564,8 +586,70 @@ http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>ActionController<span style="color: #990000">::</span>Base<span style="color: #990000">.</span>cache_store <span style="color: #990000">=</span> MyOwnStore<span style="color: #990000">.</span>new<span style="color: #990000">(</span><span style="color: #FF0000">"parameter"</span><span style="color: #990000">)</span>
</tt></pre></div></div>
<div class="para"><p><tt>Note: config.cache_store can be used in place of
ActionController::Base.cache_store in your Rails::Initializer.run block in
environment.rb</tt></p></div>
</div>
<h2 id="_advanced_caching">2. Advanced Caching</h2>
<h2 id="_conditional_get_support">2. Conditional GET support</h2>
<div class="sectionbody">
<div class="para"><p>Conditional GETs are a facility of the HTTP spec that provide a way for web
servers to tell browsers that the response to a GET request hasnt changed
since the last request and can be safely pulled from the browser cache.</p></div>
<div class="para"><p>They work by using the HTTP_IF_NONE_MATCH and HTTP_IF_MODIFIED_SINCE headers to
pass back and forth both a unique content identifier and the timestamp of when
the content was last changed. If the browser makes a request where the content
identifier (etag) or last modified since timestamp matches the servers version
then the server only needs to send back an empty response with a not modified
status.</p></div>
<div class="para"><p>It is the servers (i.e. our) responsibility to look for a last modified
timestamp and the if-none-match header and determine whether or not to send
back the full response. With conditional-get support in rails this is a pretty
easy task:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> ProductsController <span style="color: #990000">&lt;</span> ApplicationController
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> show
<span style="color: #009900">@product</span> <span style="color: #990000">=</span> Product<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>id<span style="color: #990000">])</span>
<span style="font-style: italic"><span style="color: #9A1900"># If the request is stale according to the given timestamp and etag value</span></span>
<span style="font-style: italic"><span style="color: #9A1900"># (i.e. it needs to be processed again) then execute this block</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> stale?<span style="color: #990000">(:</span>last_modified <span style="color: #990000">=&gt;</span> <span style="color: #009900">@product</span><span style="color: #990000">.</span>updated_at<span style="color: #990000">.</span>utc<span style="color: #990000">,</span> <span style="color: #990000">:</span>etag <span style="color: #990000">=&gt;</span> <span style="color: #009900">@product</span><span style="color: #990000">)</span>
respond_to <span style="font-weight: bold"><span style="color: #0000FF">do</span></span> <span style="color: #990000">|</span>wants<span style="color: #990000">|</span>
<span style="font-style: italic"><span style="color: #9A1900"># ... normal response processing</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-style: italic"><span style="color: #9A1900"># If the request is fresh (i.e. it's not modified) then you don't need to do</span></span>
<span style="font-style: italic"><span style="color: #9A1900"># anything. The default render checks for this using the parameters</span></span>
<span style="font-style: italic"><span style="color: #9A1900"># used in the previous call to stale? and will automatically send a</span></span>
<span style="font-style: italic"><span style="color: #9A1900"># :not_modified. So that's it, you're done.</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>If you dont have any special response processing and are using the default
rendering mechanism (i.e. youre not using respond_to or calling render
yourself) then youve got an easy helper in fresh_when:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> ProductsController <span style="color: #990000">&lt;</span> ApplicationController
<span style="font-style: italic"><span style="color: #9A1900"># This will automatically send back a :not_modified if the request is fresh,</span></span>
<span style="font-style: italic"><span style="color: #9A1900"># and will render the default template (product.*) if it's stale.</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> show
<span style="color: #009900">@product</span> <span style="color: #990000">=</span> Product<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>id<span style="color: #990000">])</span>
fresh_when <span style="color: #990000">:</span>last_modified <span style="color: #990000">=&gt;</span> <span style="color: #009900">@product</span><span style="color: #990000">.</span>published_at<span style="color: #990000">.</span>utc<span style="color: #990000">,</span> <span style="color: #990000">:</span>etag <span style="color: #990000">=&gt;</span> <span style="color: #009900">@article</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
</div>
<h2 id="_advanced_caching">3. Advanced Caching</h2>
<div class="sectionbody">
<div class="para"><p>Along with the built-in mechanisms outlined above, a number of excellent
plugins exist to help with finer grained control over caching. These include

View file

@ -377,7 +377,7 @@ Installed Generators
<td class="icon">
<img src="./images/icons/note.png" alt="Note" />
</td>
<td class="content">All Rails console utilities have help text. For commands that require a lot of input to run correctly, you can just try the command without any parameters (like <tt>rails</tt> or <tt>./script/generate</tt>). For others, you can try adding <tt>&#8212;help</tt> or <tt>-h</tt> to the end, as in <tt>./script/server &#8212;help</tt>.</td>
<td class="content">All Rails console utilities have help text. For commands that require a lot of input to run correctly, you can try the command without any parameters (like <tt>rails</tt> or <tt>./script/generate</tt>). For others, you can try adding <tt>&#8212;help</tt> or <tt>-h</tt> to the end, as in <tt>./script/server &#8212;help</tt>.</td>
</tr></table>
</div>
<div class="listingblock">
@ -425,7 +425,130 @@ http://www.gnu.org/software/src-highlite -->
create app/helpers/greetings_helper<span style="color: #990000">.</span>rb
create app/views/greetings/hello<span style="color: #990000">.</span>html<span style="color: #990000">.</span>erb
</tt></pre></div></div>
<div class="para"><p>Look there! Now what all did this generate? It looks like it made sure a bunch of directories were in our application, and created a controller file, a functional test file, a helper for the view, and a view file. All from one command!</p></div>
<div class="para"><p>Look there! Now what all did this generate? It looks like it made sure a bunch of directories were in our application, and created a controller file, a functional test file, a helper for the view, and a view file.</p></div>
<div class="para"><p>Let's check out the controller and modify it a little (in <tt>app/controllers/greeting_controller.rb</tt>):</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> GreetingController <span style="color: #990000">&lt;</span> ApplicationController
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> hello
<span style="color: #009900">@message</span> <span style="color: #990000">=</span> <span style="color: #FF0000">"Hello, how are you today? I am exuberant!"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>Then the view, to display our nice message (in <tt>app/views/greeting/hello.html.erb</tt>):</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">&lt;h1&gt;</span></span>A Greeting for You!<span style="font-weight: bold"><span style="color: #0000FF">&lt;/h1&gt;</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">&lt;p&gt;</span></span>&lt;%= @message %&gt;<span style="font-weight: bold"><span style="color: #0000FF">&lt;/p&gt;</span></span>
</tt></pre></div></div>
<div class="para"><p>Deal. Go check it out in your browser. Fire up your server. Remember? <tt>./script/server</tt> at the root of your Rails application should do it.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>$ <span style="color: #990000">.</span>/script/server
<span style="color: #990000">=&gt;</span> Booting WEBrick<span style="color: #990000">...</span>
</tt></pre></div></div>
<div class="para"><p>The URL will be <tt>http://localhost:3000/greetings/hello</tt>. I'll wait for you to be suitably impressed.</p></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<img src="./images/icons/note.png" alt="Note" />
</td>
<td class="content">With a normal, plain-old Rails application, your URLs will generally follow the pattern of <a href="http://(host)/(controller)/(action">http://(host)/(controller)/(action</a>), and a URL like <a href="http://(host)/(controller">http://(host)/(controller</a>) will hit the <strong>index</strong> action of that controller.</td>
</tr></table>
</div>
<div class="para"><p>"What about data, though?", you ask over a cup of coffee. Rails comes with a generator for data models too. Can you guess its generator name?</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>$ <span style="color: #990000">.</span>/script/generate model
Usage<span style="color: #990000">:</span> <span style="color: #990000">.</span>/script/generate model ModelName <span style="color: #990000">[</span>field<span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">type</span></span><span style="color: #990000">,</span> field<span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">type</span></span><span style="color: #990000">]</span>
<span style="color: #990000">...</span>
Examples<span style="color: #990000">:</span>
`<span style="color: #990000">.</span>/script/generate model account`
creates an Account model<span style="color: #990000">,</span> <span style="font-weight: bold"><span style="color: #0000FF">test</span></span><span style="color: #990000">,</span> fixture<span style="color: #990000">,</span> and migration<span style="color: #990000">:</span>
Model<span style="color: #990000">:</span> app/models/account<span style="color: #990000">.</span>rb
Test<span style="color: #990000">:</span> test/unit/account_test<span style="color: #990000">.</span>rb
Fixtures<span style="color: #990000">:</span> test/fixtures/accounts<span style="color: #990000">.</span>yml
Migration<span style="color: #990000">:</span> db/migrate/XXX_add_accounts<span style="color: #990000">.</span>rb
`<span style="color: #990000">.</span>/script/generate model post title<span style="color: #990000">:</span>string body<span style="color: #990000">:</span>text published<span style="color: #990000">:</span>boolean`
creates a Post model with a string title<span style="color: #990000">,</span> text body<span style="color: #990000">,</span> and published flag<span style="color: #990000">.</span>
</tt></pre></div></div>
<div class="para"><p>Let's set up a simple model called "HighScore" that will keep track of our highest score on video games we play. Then we'll wire up our controller and view to modify and list our scores.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>$ <span style="color: #990000">.</span>/script/generate model HighScore id<span style="color: #990000">:</span>integer game<span style="color: #990000">:</span>string score<span style="color: #990000">:</span>integer
exists app/models<span style="color: #990000">/</span>
exists test/unit<span style="color: #990000">/</span>
exists test/fixtures<span style="color: #990000">/</span>
create app/models/high_score<span style="color: #990000">.</span>rb
create test/unit/high_score_test<span style="color: #990000">.</span>rb
create test/fixtures/high_scores<span style="color: #990000">.</span>yml
create db/migrate
create db/migrate<span style="color: #990000">/</span>20081126032945_create_high_scores<span style="color: #990000">.</span>rb
</tt></pre></div></div>
<div class="para"><p>Taking it from the top, we have the <strong>models</strong> directory, where all of your data models live. <strong>test/unit</strong>, where all the unit tests live (gasp! &#8212; unit tests!), fixtures for those tests, a test, the <strong>migrate</strong> directory, where the database-modifying migrations live, and a migration to create the <tt>high_scores</tt> table with the right fields.</p></div>
<div class="para"><p>The migration requires that we <strong>migrate</strong>, that is, run some Ruby code (living in that <tt>20081126032945_create_high_scores.rb</tt>) to modify the schema of our database. Which database? The sqlite3 database that Rails will create for you when we run the <tt>rake db:migrate</tt> command. We'll talk more about Rake in-depth in a little while.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>$ rake db<span style="color: #990000">:</span>migrate
<span style="color: #990000">(</span><span style="font-weight: bold"><span style="color: #0000FF">in</span></span> /home/commandsapp<span style="color: #990000">)</span>
<span style="color: #990000">==</span> CreateHighScores<span style="color: #990000">:</span> migrating <span style="color: #990000">===============================================</span>
-- create_table<span style="color: #990000">(:</span>high_scores<span style="color: #990000">)</span>
-<span style="color: #990000">&gt;</span> <span style="color: #993399">0</span><span style="color: #990000">.</span>0070s
<span style="color: #990000">==</span> CreateHighScores<span style="color: #990000">:</span> migrated <span style="color: #990000">(</span><span style="color: #993399">0</span><span style="color: #990000">.</span>0077s<span style="color: #990000">)</span> <span style="color: #990000">======================================</span>
</tt></pre></div></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<img src="./images/icons/note.png" alt="Note" />
</td>
<td class="content">Let's talk about unit tests. Unit tests are code that tests and makes assertions about code. In unit testing, we take a little part of code, say a method of a model, and test its inputs and outputs. Unit tests are your friend. The sooner you make peace with the fact that your quality of life will drastically increase when you unit test your code, the better. Seriously. We'll make one in a moment.</td>
</tr></table>
</div>
<div class="para"><p>Yo! Let's shove a small table into our greeting controller and view, listing our sweet scores.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> GreetingController <span style="color: #990000">&lt;</span> ApplicationController
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> hello
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> request<span style="color: #990000">.</span>post?
score <span style="color: #990000">=</span> HighScore<span style="color: #990000">.</span>new<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>high_score<span style="color: #990000">])</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> score<span style="color: #990000">.</span>save
flash<span style="color: #990000">[:</span>notice<span style="color: #990000">]</span> <span style="color: #990000">=</span> <span style="color: #FF0000">"New score posted!"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="color: #009900">@scores</span> <span style="color: #990000">=</span> HighScore<span style="color: #990000">.</span>find<span style="color: #990000">(:</span>all<span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>XXX: Go with scaffolding instead, modifying greeting controller for high scores seems dumb.</p></div>
</div>
</div>

View file

@ -205,6 +205,9 @@ ul#navMain {
<a href="#_using_a_preinitializer">Using a Preinitializer</a>
</li>
<li>
<a href="#_initialization_process_settings">Initialization Process Settings</a>
</li>
<li>
<a href="#_configuring_rails_components">Configuring Rails Components</a>
<ul>
@ -220,6 +223,8 @@ ul#navMain {
<li><a href="#_configuring_active_support">Configuring Active Support</a></li>
<li><a href="#_configuring_active_model">Configuring Active Model</a></li>
</ul>
</li>
<li>
@ -229,6 +234,9 @@ ul#navMain {
<a href="#_using_an_after_initializer">Using an After-Initializer</a>
</li>
<li>
<a href="#_rails_environment_settings">Rails Environment Settings</a>
</li>
<li>
<a href="#_changelog">Changelog</a>
</li>
</ol>
@ -264,26 +272,156 @@ after-initializer</p></div>
<h2 id="_using_a_preinitializer">2. Using a Preinitializer</h2>
<div class="sectionbody">
</div>
<h2 id="_configuring_rails_components">3. Configuring Rails Components</h2>
<h2 id="_initialization_process_settings">3. Initialization Process Settings</h2>
<div class="sectionbody">
<h3 id="_configuring_active_record">3.1. Configuring Active Record</h3>
<h3 id="_configuring_action_controller">3.2. Configuring Action Controller</h3>
<h3 id="_configuring_action_view">3.3. Configuring Action View</h3>
<h3 id="_configuring_action_mailer">3.4. Configuring Action Mailer</h3>
<h3 id="_configuring_active_resource">3.5. Configuring Active Resource</h3>
<h3 id="_configuring_active_support">3.6. Configuring Active Support</h3>
</div>
<h2 id="_using_initializers">4. Using Initializers</h2>
<h2 id="_configuring_rails_components">4. Configuring Rails Components</h2>
<div class="sectionbody">
<h3 id="_configuring_active_record">4.1. Configuring Active Record</h3>
<div class="para"><p><tt>ActiveRecord::Base</tt> includej a variety of configuration options:</p></div>
<div class="para"><p><tt>logger</tt> accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then passed on to any new database connections made. You can retrieve this logger by calling <tt>logger</tt> on either an ActiveRecord model class or an ActiveRecord model instance. Set to nil to disable logging.</p></div>
<div class="para"><p><tt>primary_key_prefix_type</tt> lets you adjust the naming for primary key columns. By default, Rails assumes that primary key columns are named <tt>id</tt> (and this configuration option doesn't need to be set.) There are two other choices:</p></div>
<div class="ilist"><ul>
<li>
<p>
<tt>:table_name</tt> would make the primary key for the Customer class <tt>customerid</tt>
</p>
</li>
<li>
<p>
<tt>:table_name_with_underscore</tt> would make the primary key for the Customer class <tt>customer_id</tt>
</p>
</li>
</ul></div>
<div class="para"><p><tt>table_name_prefix</tt> lets you set a global string to be prepended to table names. If you set this to <tt>northwest_</tt>, then the Customer class will look for <tt>northwest_customers</tt> as its table. The default is an empty string.</p></div>
<div class="para"><p><tt>table_name_suffix</tt> lets you set a global string to be appended to table names. If you set this to <tt>_northwest</tt>, then the Customer class will look for <tt>customers_northwest</tt> as its table. The default is an empty string.</p></div>
<div class="para"><p><tt>pluralize_table_names</tt> specifies whether Rails will look for singular or plural table names in the database. If set to <tt>true</tt> (the default), then the Customer class will use the <tt>customers</tt> table. If set to <tt>false</tt>, then the Customers class will use the <tt>customer</tt> table.</p></div>
<div class="para"><p><tt>colorize_logging</tt> (true by default) specifies whether or not to use ANSI color codes when logging information from ActiveRecord.</p></div>
<div class="para"><p><tt>default_timezone</tt> determines whether to use <tt>Time.local</tt> (if set to <tt>:local</tt>) or <tt>Time.utc</tt> (if set to <tt>:utc</tt>) when pulling dates and times from the database. The default is <tt>:local</tt>.</p></div>
<div class="para"><p><tt>schema_format</tt> controls the format for dumping the database schema to a file. The options are <tt>:ruby</tt> (the default) for a database-independent version that depends on migrations, or <tt>:sql</tt> for a set of (potentially database-dependent) SQL statements.</p></div>
<div class="para"><p><tt>timestamped_migrations</tt> controls whether migrations are numbered with serial integers or with timestamps. The default is <tt>true</tt>, to use timestamps, which are preferred if there are multiple developers working on the same application.</p></div>
<div class="para"><p><tt>lock_optimistically</tt> controls whether ActiveRecord will use optimistic locking. By default this is <tt>true</tt>.</p></div>
<div class="para"><p>The MySQL adapter adds one additional configuration option:</p></div>
<div class="para"><p><tt>ActiveRecord::ConnectionAdapters::MysqlAdapter.emulate_booleans</tt> controls whether ActiveRecord will consider all <tt>tinyint(1)</tt> columns in a MySQL database to be booleans. By default this is <tt>true</tt>.</p></div>
<div class="para"><p>The schema dumper adds one additional configuration option:</p></div>
<div class="para"><p><tt>ActiveRecord::SchemaDumper.ignore_tables</tt> accepts an array of tables that should <em>not</em> be included in any generated schema file. This setting is ignored unless <tt>ActiveRecord::Base.schema_format == :ruby</tt>.</p></div>
<h3 id="_configuring_action_controller">4.2. Configuring Action Controller</h3>
<div class="para"><p>ActionController::Base includes a number of configuration settings:</p></div>
<div class="para"><p><tt>asset_host</tt> provides a string that is prepended to all of the URL-generating helpers in <tt>AssetHelper</tt>. This is designed to allow moving all javascript, CSS, and image files to a separate asset host.</p></div>
<div class="para"><p><tt>consider_all_requests_local</tt> is generally set to <tt>true</tt> during development and <tt>false</tt> during production; if it is set to <tt>true</tt>, then any error will cause detailed debugging information to be dumped in the HTTP response. For finer-grained control, set this to <tt>false</tt> and implement <tt>local_request?</tt> to specify which requests should provide debugging information on errors.</p></div>
<div class="para"><p><tt>allow_concurrency</tt> should be set to <tt>true</tt> to allow concurrent (threadsafe) action processing. Set to <tt>false</tt> by default.</p></div>
<div class="para"><p><tt>param_parsers</tt> provides an array of handlers that can extract information from incoming HTTP requests and add it to the <tt>params</tt> hash. By default, parsers for multipart forms, URL-encoded forms, XML, and JSON are active.</p></div>
<div class="para"><p><tt>default_charset</tt> specifies the default character set for all renders. The default is "utf-8".</p></div>
<div class="para"><p><tt>logger</tt> accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then used to log information from Action Controller. Set to nil to disable logging.</p></div>
<div class="para"><p><tt>resource_action_separator</tt> gives the token to be used between resources and actions when building or interpreting RESTful URLs. By default, this is "/".</p></div>
<div class="para"><p><tt>resource_path_names</tt> is a hash of default names for several RESTful actions. By default, the new action is named <tt>new</tt> and the edit action is named <tt>edit</tt>.</p></div>
<div class="para"><p><tt>request_forgery_protection_token</tt> sets the token parameter name for RequestForgery. Calling <tt>protect_from_forgery</tt> sets it to <tt>:authenticity_token</tt> by default.</p></div>
<div class="para"><p><tt>optimise_named_routes</tt> turns on some optimizations in generating the routing table. It is set to <tt>true</tt> by default.</p></div>
<div class="para"><p><tt>use_accept_header</tt> sets the rules for determining the response format. If this is set to <tt>true</tt> (the default) then <tt>respond_to</tt> and <tt>Request#format</tt> will take the Accept header into account. If it is set to false then the request format will be determined solely by examining <tt>params[:format]</tt>. If there is no <tt>format</tt> parameter, then the response format will be either HTML or Javascript depending on whether the request is an AJAX request.</p></div>
<div class="para"><p><tt>allow_forgery_protection</tt> enables or disables CSRF protection. By default this is <tt>false</tt> in test mode and <tt>true</tt> in all other modes.</p></div>
<div class="para"><p><tt>relative_url_root</tt> can be used to tell Rails that you are deploying to a subdirectory. The default is <tt>ENV[<em>RAILS_RELATIVE_URL_ROOT</em>]</tt>.</p></div>
<div class="para"><p>The caching code adds two additional settings:</p></div>
<div class="para"><p><tt>ActionController::Caching::Pages.page_cache_directory</tt> sets the directory where Rails will create cached pages for your web server. The default is <tt>Rails.public_path</tt> (which is usually set to <tt>RAILS_ROOT </tt> "/public"+).</p></div>
<div class="para"><p><tt>ActionController::Caching::Pages.page_cache_extension</tt> sets the extension to be used when generating pages for the cache (this is ignored if the incoming request already has an extension). The default is <tt>.html</tt>.</p></div>
<div class="para"><p>The dispatcher includes one setting:</p></div>
<div class="para"><p><tt>ActionController::Dispatcher.error_file_path</tt> gives the path where Rails will look for error files such as <tt>404.html</tt>. The default is <tt>Rails.public_path</tt>.</p></div>
<div class="para"><p>The Active Record session store can also be configured:</p></div>
<div class="para"><p><tt>CGI::Session::ActiveRecordStore::Session.data_column_name</tt> sets the name of the column to use to store session data. By default it is <em>data</em></p></div>
<h3 id="_configuring_action_view">4.3. Configuring Action View</h3>
<div class="para"><p>There are only a few configuration options for Action View, starting with four on <tt>ActionView::Base</tt>:</p></div>
<div class="para"><p><tt>debug_rjs</tt> specifies whether RJS responses should be wrapped in a try/catch block that alert()s the caught exception (and then re-raises it). The default is <tt>false</tt>.</p></div>
<div class="para"><p><tt>warn_cache_misses</tt> tells Rails to display a warning whenever an action results in a cache miss on your view paths. The default is <tt>false</tt>.</p></div>
<div class="para"><p></p></div>
<div class="para"><p><tt>default_form_builder</tt> tells Rails which form builder to use by default. The default is <tt>ActionView::Helpers::FormBuilder</tt>.</p></div>
<div class="para"><p>The ERB template handler supplies one additional option:</p></div>
<div class="para"><p><tt>ActionView::TemplateHandlers::ERB.erb_trim_mode</tt> gives the trim mode to be used by ERB. It defaults to <tt><em>-</em></tt>. See the <a href="http://www.ruby-doc.org/stdlib/libdoc/erb/rdoc/">ERB documentation</a> for more information.</p></div>
<h3 id="_configuring_action_mailer">4.4. Configuring Action Mailer</h3>
<div class="para"><p>There are a number of settings available on <tt>ActionMailer::Base</tt>:</p></div>
<div class="para"><p><tt>template_root</tt> gives the root folder for Action Mailer templates.</p></div>
<div class="para"><p><tt>logger</tt> accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then used to log information from Action Mailer. Set to nil to disable logging.</p></div>
<div class="para"><p><tt>smtp_settings</tt> allows detailed configuration for the <tt>:smtp</tt> delivery method. It accepts a hash of options, which can include any of these options:</p></div>
<div class="ilist"><ul>
<li>
<p>
&lt;tt&gt;:address&lt;/tt&gt; - Allows you to use a remote mail server. Just change it from its default "localhost" setting.
</p>
</li>
<li>
<p>
&lt;tt&gt;:port&lt;/tt&gt; - On the off chance that your mail server doesn't run on port 25, you can change it.
</p>
</li>
<li>
<p>
&lt;tt&gt;:domain&lt;/tt&gt; - If you need to specify a HELO domain, you can do it here.
</p>
</li>
<li>
<p>
&lt;tt&gt;:user_name&lt;/tt&gt; - If your mail server requires authentication, set the username in this setting.
</p>
</li>
<li>
<p>
&lt;tt&gt;:password&lt;/tt&gt; - If your mail server requires authentication, set the password in this setting.
</p>
</li>
<li>
<p>
&lt;tt&gt;:authentication&lt;/tt&gt; - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of &lt;tt&gt;:plain&lt;/tt&gt;, &lt;tt&gt;:login&lt;/tt&gt;, &lt;tt&gt;:cram_md5&lt;/tt&gt;.
</p>
</li>
</ul></div>
<div class="para"><p><tt>sendmail_settings</tt> allows detailed configuration for the <tt>sendmail</tt> delivery method. It accepts a hash of options, which can include any of these options:</p></div>
<div class="ilist"><ul>
<li>
<p>
&lt;tt&gt;:location&lt;/tt&gt; - The location of the sendmail executable. Defaults to &lt;tt&gt;/usr/sbin/sendmail&lt;/tt&gt;.
</p>
</li>
<li>
<p>
&lt;tt&gt;:arguments&lt;/tt&gt; - The command line arguments. Defaults to &lt;tt&gt;-i -t&lt;/tt&gt;.
</p>
</li>
</ul></div>
<div class="para"><p><tt>raise_delivery_errors</tt> specifies whether to raise an error if email delivery cannot be completed. It defaults to <tt>true</tt>.</p></div>
<div class="para"><p><tt>delivery_method</tt> defines the delivery method. The allowed values are &lt;tt&gt;:smtp&lt;/tt&gt; (default), &lt;tt&gt;:sendmail&lt;/tt&gt;, and &lt;tt&gt;:test&lt;/tt&gt;.</p></div>
<div class="para"><p><tt>perform_deliveries</tt> specifies whether mail will actually be delivered. By default this is <tt>true</tt>; it can be convenient to set it to <tt>false</tt> for testing.</p></div>
<div class="para"><p><tt>default_charset</tt> tells Action Mailer which character set to use for the body and for encoding the subject. It defaults to <tt>utf-8</tt>.</p></div>
<div class="para"><p><tt>default_content_type</tt> specifies the default content type used for the main part of the message. It defaults to "text/plain"</p></div>
<div class="para"><p><tt>default_mime_version</tt> is the default MIME version for the message. It defaults to <tt>1.0</tt>.</p></div>
<div class="para"><p><tt>default_implicit_parts_order</tt> - When a message is built implicitly (i.e. multiple parts are assembled from templates
which specify the content type in their filenames) this variable controls how the parts are ordered. Defaults to
&lt;tt&gt;["text/html", "text/enriched", "text/plain"]&lt;/tt&gt;. Items that appear first in the array have higher priority in the mail client
and appear last in the mime encoded message.</p></div>
<h3 id="_configuring_active_resource">4.5. Configuring Active Resource</h3>
<div class="para"><p>There is a single configuration setting available on <tt>ActiveResource::Base</tt>:</p></div>
<div class="para"><p><tt>logger</tt> accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then used to log information from Active Resource. Set to nil to disable logging.</p></div>
<h3 id="_configuring_active_support">4.6. Configuring Active Support</h3>
<div class="para"><p>There are a few configuration options available in Active Support:</p></div>
<div class="para"><p><tt>ActiveSupport::BufferedLogger.silencer</tt> is set to <tt>false</tt> to disable the ability to silence logging in a block. The default is <tt>true</tt>.</p></div>
<div class="para"><p><tt>ActiveSupport::Cache::Store.logger</tt> specifies the logger to use within cache store operations.</p></div>
<div class="para"><p><tt>ActiveSupport::Logger.silencer</tt> is set to <tt>false</tt> to disable the ability to silence logging in a block. The default is <tt>true</tt>.</p></div>
<h3 id="_configuring_active_model">4.7. Configuring Active Model</h3>
<div class="para"><p>Active Model currently has a single configuration setting:</p></div>
<div class="para"><p>+ActiveModel::Errors.default_error_messages is an array containing all of the validation error messages.</p></div>
</div>
<h2 id="_using_initializers">5. Using Initializers</h2>
<div class="sectionbody">
<div class="literalblock">
<div class="content">
<pre><tt>organization, controlling load order</tt></pre>
</div></div>
</div>
<h2 id="_using_an_after_initializer">5. Using an After-Initializer</h2>
<h2 id="_using_an_after_initializer">6. Using an After-Initializer</h2>
<div class="sectionbody">
</div>
<h2 id="_changelog">6. Changelog</h2>
<h2 id="_rails_environment_settings">7. Rails Environment Settings</h2>
<div class="sectionbody">
<div class="para"><p>ENV</p></div>
</div>
<h2 id="_changelog">8. Changelog</h2>
<div class="sectionbody">
<div class="para"><p><a href="http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/28">Lighthouse ticket</a></p></div>
<div class="ilist"><ul>
@ -291,145 +429,15 @@ after-initializer</p></div>
<p>
November 5, 2008: Rough outline by <a href="../authors.html#mgunderloy">Mike Gunderloy</a>
</p>
<div class="qlist"><ol>
<li>
<p><em>
need to look for def self. ?
</em></p>
</li>
</ol></div>
</li>
</ul></div>
<div class="para"><p>actionmailer/lib/action_mailer/base.rb
257: cattr_accessor :logger
267: cattr_accessor :smtp_settings
273: cattr_accessor :sendmail_settings
276: cattr_accessor :raise_delivery_errors
282: cattr_accessor :perform_deliveries
285: cattr_accessor :deliveries
288: cattr_accessor :default_charset
291: cattr_accessor :default_content_type
294: cattr_accessor :default_mime_version
297: cattr_accessor :default_implicit_parts_order
299: cattr_reader :protected_instance_variables</p></div>
<div class="para"><p>actionmailer/Rakefile
36: rdoc.options &lt;&lt; <em>&#8212;line-numbers</em> &lt;&lt; <em>&#8212;inline-source</em> &lt;&lt; <em>-A cattr_accessor=object</em></p></div>
<div class="para"><p>actionpack/lib/action_controller/base.rb
263: cattr_reader :protected_instance_variables
273: cattr_accessor :asset_host
279: cattr_accessor :consider_all_requests_local
285: cattr_accessor :allow_concurrency
317: cattr_accessor :param_parsers
321: cattr_accessor :default_charset
325: cattr_accessor :logger
329: cattr_accessor :resource_action_separator
333: cattr_accessor :resources_path_names
337: cattr_accessor :request_forgery_protection_token
341: cattr_accessor :optimise_named_routes
351: cattr_accessor :use_accept_header
361: cattr_accessor :relative_url_root</p></div>
<div class="para"><p>actionpack/lib/action_controller/caching/pages.rb
55: cattr_accessor :page_cache_directory
58: cattr_accessor :page_cache_extension</p></div>
<div class="para"><p>actionpack/lib/action_controller/caching.rb
37: cattr_reader :cache_store
48: cattr_accessor :perform_caching</p></div>
<div class="para"><p>actionpack/lib/action_controller/dispatcher.rb
98: cattr_accessor :error_file_path</p></div>
<div class="para"><p>actionpack/lib/action_controller/mime_type.rb
24: cattr_reader :html_types, :unverifiable_types</p></div>
<div class="para"><p>actionpack/lib/action_controller/rescue.rb
36: base.cattr_accessor :rescue_responses
40: base.cattr_accessor :rescue_templates</p></div>
<div class="para"><p>actionpack/lib/action_controller/session/active_record_store.rb
60: cattr_accessor :data_column_name
170: cattr_accessor :connection
173: cattr_accessor :table_name
177: cattr_accessor :session_id_column
181: cattr_accessor :data_column
282: cattr_accessor :session_class</p></div>
<div class="para"><p>actionpack/lib/action_controller/vendor/html-scanner/html/sanitizer.rb
44: cattr_accessor :included_tags, :instance_writer &#8658; false</p></div>
<div class="para"><p>actionpack/lib/action_view/base.rb
189: cattr_accessor :debug_rjs
193: cattr_accessor :warn_cache_misses</p></div>
<div class="para"><p>actionpack/lib/action_view/helpers/active_record_helper.rb
7: cattr_accessor :field_error_proc</p></div>
<div class="para"><p>actionpack/lib/action_view/helpers/form_helper.rb
805: cattr_accessor :default_form_builder</p></div>
<div class="para"><p>actionpack/lib/action_view/template_handlers/erb.rb
47: cattr_accessor :erb_trim_mode</p></div>
<div class="para"><p>actionpack/test/active_record_unit.rb
5: cattr_accessor :able_to_connect
6: cattr_accessor :connected</p></div>
<div class="para"><p>actionpack/test/controller/filters_test.rb
286: cattr_accessor :execution_log</p></div>
<div class="para"><p>actionpack/test/template/form_options_helper_test.rb
3:TZInfo::Timezone.cattr_reader :loaded_zones</p></div>
<div class="para"><p>activemodel/lib/active_model/errors.rb
28: cattr_accessor :default_error_messages</p></div>
<div class="para"><p>activemodel/Rakefile
19: rdoc.options &lt;&lt; <em>&#8212;line-numbers</em> &lt;&lt; <em>&#8212;inline-source</em> &lt;&lt; <em>-A cattr_accessor=object</em></p></div>
<div class="para"><p>activerecord/lib/active_record/attribute_methods.rb
9: base.cattr_accessor :attribute_types_cached_by_default, :instance_writer &#8658; false
11: base.cattr_accessor :time_zone_aware_attributes, :instance_writer &#8658; false</p></div>
<div class="para"><p>activerecord/lib/active_record/base.rb
394: cattr_accessor :logger, :instance_writer &#8658; false
443: cattr_accessor :configurations, :instance_writer &#8658; false
450: cattr_accessor :primary_key_prefix_type, :instance_writer &#8658; false
456: cattr_accessor :table_name_prefix, :instance_writer &#8658; false
461: cattr_accessor :table_name_suffix, :instance_writer &#8658; false
467: cattr_accessor :pluralize_table_names, :instance_writer &#8658; false
473: cattr_accessor :colorize_logging, :instance_writer &#8658; false
478: cattr_accessor :default_timezone, :instance_writer &#8658; false
487: cattr_accessor :schema_format , :instance_writer &#8658; false
491: cattr_accessor :timestamped_migrations , :instance_writer &#8658; false</p></div>
<div class="para"><p>activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
11: cattr_accessor :connection_handler, :instance_writer &#8658; false</p></div>
<div class="para"><p>activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
166: cattr_accessor :emulate_booleans</p></div>
<div class="para"><p>activerecord/lib/active_record/fixtures.rb
498: cattr_accessor :all_loaded_fixtures</p></div>
<div class="para"><p>activerecord/lib/active_record/locking/optimistic.rb
38: base.cattr_accessor :lock_optimistically, :instance_writer &#8658; false</p></div>
<div class="para"><p>activerecord/lib/active_record/migration.rb
259: cattr_accessor :verbose</p></div>
<div class="para"><p>activerecord/lib/active_record/schema_dumper.rb
13: cattr_accessor :ignore_tables</p></div>
<div class="para"><p>activerecord/lib/active_record/serializers/json_serializer.rb
4: base.cattr_accessor :include_root_in_json, :instance_writer &#8658; false</p></div>
<div class="para"><p>activerecord/Rakefile
142: rdoc.options &lt;&lt; <em>&#8212;line-numbers</em> &lt;&lt; <em>&#8212;inline-source</em> &lt;&lt; <em>-A cattr_accessor=object</em></p></div>
<div class="para"><p>activerecord/test/cases/lifecycle_test.rb
61: cattr_reader :last_inherited</p></div>
<div class="para"><p>activerecord/test/cases/mixin_test.rb
9: cattr_accessor :forced_now_time</p></div>
<div class="para"><p>activeresource/lib/active_resource/base.rb
206: cattr_accessor :logger</p></div>
<div class="para"><p>activeresource/Rakefile
43: rdoc.options &lt;&lt; <em>&#8212;line-numbers</em> &lt;&lt; <em>&#8212;inline-source</em> &lt;&lt; <em>-A cattr_accessor=object</em></p></div>
<div class="para"><p>activesupport/lib/active_support/buffered_logger.rb
17: cattr_accessor :silencer</p></div>
<div class="para"><p>activesupport/lib/active_support/cache.rb
81: cattr_accessor :logger</p></div>
<div class="para"><p>activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
5:# cattr_accessor :hair_colors
10: def cattr_reader(*syms)
29: def cattr_writer(*syms)
50: def cattr_accessor(*syms)
51: cattr_reader(*syms)
52: cattr_writer(*syms)</p></div>
<div class="para"><p>activesupport/lib/active_support/core_ext/logger.rb
34: cattr_accessor :silencer</p></div>
<div class="para"><p>activesupport/test/core_ext/class/attribute_accessor_test.rb
6: cattr_accessor :foo
7: cattr_accessor :bar, :instance_writer &#8658; false</p></div>
<div class="para"><p>activesupport/test/core_ext/module/synchronization_test.rb
6: @target.cattr_accessor :mutex, :instance_writer &#8658; false</p></div>
<div class="para"><p>railties/doc/guides/html/creating_plugins.html
786: cattr_accessor &lt;span style="color: #990000"&gt;:&lt;/span&gt;yaffle_text_field&lt;span style="color: #990000"&gt;,&lt;/span&gt; &lt;span style="color: #990000"&gt;:&lt;/span&gt;yaffle_date_field
860: cattr_accessor &lt;span style="color: #990000"&gt;:&lt;/span&gt;yaffle_text_field&lt;span style="color: #990000"&gt;,&lt;/span&gt; &lt;span style="color: #990000"&gt;:&lt;/span&gt;yaffle_date_field</p></div>
<div class="para"><p>railties/lib/rails_generator/base.rb
93: cattr_accessor :logger</p></div>
<div class="para"><p>railties/Rakefile
265: rdoc.options &lt;&lt; <em>&#8212;line-numbers</em> &lt;&lt; <em>&#8212;inline-source</em> &lt;&lt; <em>&#8212;accessor</em> &lt;&lt; <em>cattr_accessor=object</em></p></div>
<div class="para"><p>railties/test/rails_info_controller_test.rb
12: cattr_accessor :local_request</p></div>
<div class="para"><p>Rakefile
32: rdoc.options &lt;&lt; <em>-A cattr_accessor=object</em></p></div>
</div>
</div>

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@ -215,7 +215,7 @@ ul#navMain {
<li><a href="#_array_conditions">Array Conditions</a></li>
<li><a href="#_hash_conditions">Hash Conditions</a></li>
<li><a href="#_placeholder_conditions">Placeholder Conditions</a></li>
</ul>
</li>
@ -344,6 +344,7 @@ Perform aggregate calculations on Active Record models
</li>
</ul></div>
<div class="para"><p>If you're used to using raw SQL to find database records, you'll find that there are generally better ways to carry out the same operations in Rails. Active Record insulates you from the need to use SQL in most cases.</p></div>
<div class="para"><p>The SQL in your log may have some quoting, and that quoting depends on the backend (MySQL, for example, puts backticks around field and table names). Attempting to copy the raw SQL contained within this guide may not work in your database system. Please consult the database systems manual before attempting to execute any SQL.</p></div>
</div>
</div>
<h2 id="_the_sample_models">1. The Sample Models</h2>
@ -389,14 +390,14 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>clients<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(+</span>clients<span style="color: #990000">+.+</span>id<span style="color: #990000">+</span> <span style="color: #990000">=</span> <span style="color: #993399">1</span><span style="color: #990000">)</span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>clients<span style="color: #990000">.</span>id <span style="color: #990000">=</span> <span style="color: #993399">1</span><span style="color: #990000">)</span>
</tt></pre></div></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<img src="./images/icons/note.png" alt="Note" />
</td>
<td class="content">Because this is a standard table created from a migration in Rail, the primary key is defaulted to <em>id</em>. If you have specified a different primary key in your migrations, this is what Rails will find on when you call the find method, not the id column.</td>
<td class="content">Because this is a standard table created from a migration in Rails, the primary key is defaulted to <em>id</em>. If you have specified a different primary key in your migrations, this is what Rails will find on when you call the find method, not the id column.</td>
</tr></table>
</div>
<div class="para"><p>If you wanted to find clients with id 1 or 2, you call <tt>Client.find([1,2])</tt> or <tt>Client.find(1,2)</tt> and then this will be executed as:</p></div>
@ -405,7 +406,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>clients<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(+</span>clients<span style="color: #990000">+.+</span>id<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">IN</span></span> <span style="color: #990000">(</span><span style="color: #993399">1</span><span style="color: #990000">,</span><span style="color: #993399">2</span><span style="color: #990000">))</span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>clients<span style="color: #990000">.</span>id <span style="font-weight: bold"><span style="color: #0000FF">IN</span></span> <span style="color: #990000">(</span><span style="color: #993399">1</span><span style="color: #990000">,</span><span style="color: #993399">2</span><span style="color: #990000">))</span>
</tt></pre></div></div>
<div class="listingblock">
<div class="content">
@ -424,14 +425,14 @@ http://www.gnu.org/software/src-highlite -->
<td class="content">If <tt>find(id)</tt> or <tt>find([id1, id2])</tt> fails to find any records, it will raise a <tt>RecordNotFound</tt> exception.</td>
</tr></table>
</div>
<div class="para"><p>If you wanted to find the first client you would simply type <tt>Client.first</tt> and that would find the first client created in your clients table:</p></div>
<div class="para"><p>If you wanted to find the first Client object you would simply type <tt>Client.first</tt> and that would find the first client in your clients table:</p></div>
<div class="listingblock">
<div class="content">
<pre><tt>&gt;&gt; Client.first
=&gt; #&lt;Client id: 1, name: =&gt; "Ryan", locked: false, orders_count: 2,
created_at: "2008-09-28 15:38:50", updated_at: "2008-09-28 15:38:50"&gt;</tt></pre>
</div></div>
<div class="para"><p>If you were running script/server you might see the following output:</p></div>
<div class="para"><p>If you were reading your log file (the default is log/development.log) you may see something like this:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -440,13 +441,29 @@ http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients <span style="font-weight: bold"><span style="color: #0000FF">LIMIT</span></span> <span style="color: #993399">1</span>
</tt></pre></div></div>
<div class="para"><p>Indicating the query that Rails has performed on your database.</p></div>
<div class="para"><p>To find the last client you would simply type <tt>Client.find(:last)</tt> and that would find the last client created in your clients table:</p></div>
<div class="para"><p>To find the last Client object you would simply type <tt>Client.last</tt> and that would find the last client created in your clients table:</p></div>
<div class="listingblock">
<div class="content">
<pre><tt>&gt;&gt; Client.find(:last)
<pre><tt>&gt;&gt; Client.last
=&gt; #&lt;Client id: 2, name: =&gt; "Michael", locked: false, orders_count: 3,
created_at: "2008-09-28 13:12:40", updated_at: "2008-09-28 13:12:40"&gt;</tt></pre>
</div></div>
<div class="para"><p>If you were reading your log file (the default is log/development.log) you may see something like this:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients <span style="font-weight: bold"><span style="color: #0000FF">ORDER</span></span> <span style="font-weight: bold"><span style="color: #0000FF">BY</span></span> id <span style="font-weight: bold"><span style="color: #0000FF">DESC</span></span> <span style="font-weight: bold"><span style="color: #0000FF">LIMIT</span></span> <span style="color: #993399">1</span>
</tt></pre></div></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<img src="./images/icons/note.png" alt="Note" />
</td>
<td class="content">Please be aware that the syntax that Rails uses to find the first record in the table means that it may not be the actual first record. If you want the actual first record based on a field in your table (e.g. <tt>created_at</tt>) specify an order option in your find call. The last method call works differently: it finds the last record on your table based on the primary key column.</td>
</tr></table>
</div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -454,7 +471,7 @@ http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients <span style="font-weight: bold"><span style="color: #0000FF">ORDER</span></span> <span style="font-weight: bold"><span style="color: #0000FF">BY</span></span> clients<span style="color: #990000">.</span>id <span style="font-weight: bold"><span style="color: #0000FF">DESC</span></span> <span style="font-weight: bold"><span style="color: #0000FF">LIMIT</span></span> <span style="color: #993399">1</span>
</tt></pre></div></div>
<div class="para"><p>To find all the clients you would simply type <tt>Client.all</tt> and that would find all the clients in your clients table:</p></div>
<div class="para"><p>To find all the Client objects you would simply type <tt>Client.all</tt> and that would find all the clients in your clients table:</p></div>
<div class="listingblock">
<div class="content">
<pre><tt>&gt;&gt; Client.all
@ -463,8 +480,8 @@ http://www.gnu.org/software/src-highlite -->
#&lt;Client id: 2, name: =&gt; "Michael", locked: false, orders_count: 3,
created_at: "2008-09-28 13:12:40", updated_at: "2008-09-28 13:12:40"&gt;]</tt></pre>
</div></div>
<div class="para"><p>As alternatives to calling <tt>Client.first</tt>, <tt>Client.last</tt>, and <tt>Client.all</tt>, you can use the class methods <tt>Client.first</tt>, <tt>Client.last</tt>, and <tt>Client.all</tt> instead. <tt>Client.first</tt>, <tt>Client.last</tt> and <tt>Client.all</tt> just call their longer counterparts: <tt>Client.find(:first)</tt>, <tt>Client.find(:last)</tt> and <tt>Client.find(:all)</tt> respectively.</p></div>
<div class="para"><p>Be aware that <tt>Client.first</tt>/<tt>Client.find(:first)</tt> and <tt>Client.last</tt>/<tt>Client.find(:last)</tt> will both return a single object, where as <tt>Client.all</tt>/<tt>Client.find(:all)</tt> will return an array of Client objects, just as passing in an array of ids to find will do also.</p></div>
<div class="para"><p>You may see in Rails code that there are calls to methods such as <tt>Client.find(:all)</tt>, <tt>Client.find(:first)</tt> and <tt>Client.find(:last)</tt>. These methods are just alternatives to <tt>Client.all</tt>, <tt>Client.first</tt> and <tt>Client.last</tt> respectively.</p></div>
<div class="para"><p>Be aware that <tt>Client.first</tt>/<tt>Client.find(:first)</tt> and <tt>Client.last</tt>/<tt>Client.find(:last)</tt> will both return a single object, where as <tt>Client.all</tt>/<tt>Client.find(:all)</tt> will return an array of Client objects, just as passing in an array of ids to <tt>find</tt> will do also.</p></div>
</div>
<h2 id="_conditions">4. Conditions</h2>
<div class="sectionbody">
@ -480,20 +497,23 @@ http://www.gnu.org/software/src-highlite -->
</tr></table>
</div>
<h3 id="_array_conditions">4.2. Array Conditions</h3>
<div class="para"><p>Now what if that number could vary, say as a parameter from somewhere, or perhaps from the user's level status somewhere? The find then becomes something like <tt>Client.first(:conditions &#8658; ["orders_count = ?", params[:orders]])</tt>. Active Record will go through the first element in the conditions value and any additional elements will replace the question marks (?) in the first element. If you want to specify two conditions, you can do it like <tt>Client.first(:conditions &#8658; ["orders_count = ? AND locked = ?", params[:orders], false])</tt>. In this example, the first question mark will be replaced with the value in params orders and the second will be replaced with true and this will find the first record in the table that has <em>2</em> as its value for the orders_count field and <em>false</em> for its locked field.</p></div>
<div class="para"><p>Now what if that number could vary, say as a parameter from somewhere, or perhaps from the user's level status somewhere? The find then becomes something like <tt>Client.first(:conditions &#8658; ["orders_count = ?", params[:orders]])</tt>. Active Record will go through the first element in the conditions value and any additional elements will replace the question marks (?) in the first element. If you want to specify two conditions, you can do it like <tt>Client.first(:conditions &#8658; ["orders_count = ? AND locked = ?", params[:orders], false])</tt>. In this example, the first question mark will be replaced with the value in <tt>params[:orders]</tt> and the second will be replaced with <tt>false</tt> and this will find the first record in the table that has <em>2</em> as its value for the <tt>orders_count</tt> field and <tt>false</tt> for its locked field.</p></div>
<div class="para"><p>The reason for doing code like:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="color: #990000">+</span>Client<span style="color: #990000">.</span>first<span style="color: #990000">(:</span>conditions <span style="color: #990000">=&gt;</span> <span style="color: #990000">[</span><span style="color: #FF0000">"orders_count = ?"</span><span style="color: #990000">,</span> params<span style="color: #990000">[:</span>orders<span style="color: #990000">]])+</span>
<pre><tt>Client<span style="color: #990000">.</span>first<span style="color: #990000">(:</span>conditions <span style="color: #990000">=&gt;</span> <span style="color: #990000">[</span><span style="color: #FF0000">"orders_count = ?"</span><span style="color: #990000">,</span> params<span style="color: #990000">[:</span>orders<span style="color: #990000">]])</span>
</tt></pre></div></div>
<div class="para"><p>instead of:</p></div>
<div class="listingblock">
<div class="content">
<pre><tt>+Client.first(:conditions =&gt; "orders_count = #{params[:orders]}")+</tt></pre>
</div></div>
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>Client<span style="color: #990000">.</span>first<span style="color: #990000">(:</span>conditions <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"orders_count = #{params[:orders]}"</span><span style="color: #990000">)</span>
</tt></pre></div></div>
<div class="para"><p>is because of parameter safety. Putting the variable directly into the conditions string will pass the variable to the database <strong>as-is</strong>. This means that it will be an unescaped variable directly from a user who may have malicious intent. If you do this, you put your entire database at risk because once a user finds out he or she can exploit your database they can do just about anything to it. Never ever put your parameters directly inside the conditions string.</p></div>
<div class="admonitionblock">
<table><tr>
@ -518,7 +538,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>users<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>created_at <span style="font-weight: bold"><span style="color: #0000FF">IN</span></span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> users <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>created_at <span style="font-weight: bold"><span style="color: #0000FF">IN</span></span>
<span style="color: #990000">(</span><span style="color: #FF0000">'2007-12-31'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-01'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-02'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-03'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-04'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-05'</span><span style="color: #990000">,</span>
<span style="color: #FF0000">'2008-01-06'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-07'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-08'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-09'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-10'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-11'</span><span style="color: #990000">,</span>
<span style="color: #FF0000">'2008-01-12'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-13'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-14'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-15'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-16'</span><span style="color: #990000">,</span><span style="color: #FF0000">'2008-01-17'</span><span style="color: #990000">,</span>
@ -541,7 +561,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>users<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>created_at <span style="font-weight: bold"><span style="color: #0000FF">IN</span></span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> users <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>created_at <span style="font-weight: bold"><span style="color: #0000FF">IN</span></span>
<span style="color: #990000">(</span><span style="color: #FF0000">'2007-12-01 00:00:00'</span><span style="color: #990000">,</span> <span style="color: #FF0000">'2007-12-01 00:00:01'</span> <span style="color: #990000">...</span>
<span style="color: #FF0000">'2007-12-01 23:59:59'</span><span style="color: #990000">,</span> <span style="color: #FF0000">'2007-12-02 00:00:00'</span><span style="color: #990000">))</span>
</tt></pre></div></div>
@ -570,7 +590,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="color: #990000">[</span><span style="color: #FF0000">"created_at &gt;= ? AND created_at &lt;= ?"</span><span style="color: #990000">,</span> params<span style="color: #990000">[:</span>start_date<span style="color: #990000">],</span> params<span style="color: #990000">[:</span>end_date<span style="color: #990000">]])</span>
</tt></pre></div></div>
<div class="para"><p>Just like in Ruby.</p></div>
<h3 id="_hash_conditions">4.3. Hash Conditions</h3>
<h3 id="_placeholder_conditions">4.3. Placeholder Conditions</h3>
<div class="para"><p>Similar to the array style of params you can also specify keys in your conditions:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
@ -641,7 +661,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>orders<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">GROUP</span></span> <span style="font-weight: bold"><span style="color: #0000FF">BY</span></span> <span style="color: #009900">date</span><span style="color: #990000">(</span>created_at<span style="color: #990000">)</span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> orders <span style="font-weight: bold"><span style="color: #0000FF">GROUP</span></span> <span style="font-weight: bold"><span style="color: #0000FF">BY</span></span> <span style="color: #009900">date</span><span style="color: #990000">(</span>created_at<span style="color: #990000">)</span>
</tt></pre></div></div>
</div>
<h2 id="_read_only">9. Read Only</h2>
@ -730,20 +750,23 @@ http://www.gnu.org/software/src-highlite -->
</div>
<h2 id="_dynamic_finders">13. Dynamic finders</h2>
<div class="sectionbody">
<div class="para"><p>For every field (also known as an attribute) you define in your table, Active Record provides a finder method. If you have a field called <tt>name</tt> on your Client model for example, you get <tt>find_by_name</tt> and <tt>find_all_by_name</tt> for free from Active Record. If you have also have a <tt>locked</tt> field on the client model, you also get <tt>find_by_locked</tt> and <tt>find_all_by_locked</tt>. If you want to find both by name and locked, you can chain these finders together by simply typing <tt>and</tt> between the fields for example <tt>Client.find_by_name_and_locked(<em>Ryan</em>, true)</tt>. These finders are an excellent alternative to using the conditions option, mainly because it's shorter to type <tt>find_by_name(params[:name])</tt> than it is to type <tt>first(:conditions &#8658; ["name = ?", params[:name]])</tt>.</p></div>
<div class="para"><p>For every field (also known as an attribute) you define in your table, Active Record provides a finder method. If you have a field called <tt>name</tt> on your Client model for example, you get <tt>find_by_name</tt> and <tt>find_all_by_name</tt> for free from Active Record. If you have also have a <tt>locked</tt> field on the client model, you also get <tt>find_by_locked</tt> and <tt>find_all_by_locked</tt>.</p></div>
<div class="para"><p>You can do <tt>find_last_by_*</tt> methods too which will find the last record matching your parameter.</p></div>
<div class="para"><p>You can specify an exclamation point (!) on the end of the dynamic finders to get them to raise an <tt>ActiveRecord::RecordNotFound</tt> error if they do not return any records, like <tt>Client.find_by_name!(<em>Ryan</em>)</tt></p></div>
<div class="para"><p>If you want to find both by name and locked, you can chain these finders together by simply typing <tt>and</tt> between the fields for example <tt>Client.find_by_name_and_locked(<em>Ryan</em>, true)</tt>.</p></div>
<div class="para"><p>There's another set of dynamic finders that let you find or create/initialize objects if they aren't find. These work in a similar fashion to the other finders and can be used like <tt>find_or_create_by_name(params[:name])</tt>. Using this will firstly perform a find and then create if the find returns nil. The SQL looks like this for <tt>Client.find_or_create_by_name(<em>Ryan</em>)</tt>:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>clients<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(+</span>clients<span style="color: #990000">+.+</span>name<span style="color: #990000">+</span> <span style="color: #990000">=</span> <span style="color: #FF0000">'Ryan'</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">LIMIT</span></span> <span style="color: #993399">1</span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> <span style="color: #990000">*</span> <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>clients<span style="color: #990000">.</span>name <span style="color: #990000">=</span> <span style="color: #FF0000">'Ryan'</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">LIMIT</span></span> <span style="color: #993399">1</span>
BEGIN
<span style="font-weight: bold"><span style="color: #0000FF">INSERT</span></span> <span style="font-weight: bold"><span style="color: #0000FF">INTO</span></span> <span style="color: #990000">+</span>clients<span style="color: #990000">+</span> <span style="color: #990000">(+</span>name<span style="color: #990000">+,</span> <span style="color: #990000">+</span>updated_at<span style="color: #990000">+,</span> <span style="color: #990000">+</span>created_at<span style="color: #990000">+,</span> <span style="color: #990000">+</span>orders_count<span style="color: #990000">+,</span> <span style="color: #990000">+</span>locked<span style="color: #990000">+)</span>
<span style="font-weight: bold"><span style="color: #0000FF">INSERT</span></span> <span style="font-weight: bold"><span style="color: #0000FF">INTO</span></span> clients <span style="color: #990000">(</span>name<span style="color: #990000">,</span> updated_at<span style="color: #990000">,</span> created_at<span style="color: #990000">,</span> orders_count<span style="color: #990000">,</span> locked<span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">VALUES</span></span><span style="color: #990000">(</span><span style="color: #FF0000">'Ryan'</span><span style="color: #990000">,</span> <span style="color: #FF0000">'2008-09-28 15:39:12'</span><span style="color: #990000">,</span> <span style="color: #FF0000">'2008-09-28 15:39:12'</span><span style="color: #990000">,</span> <span style="color: #FF0000">'0'</span><span style="color: #990000">,</span> <span style="color: #FF0000">'0'</span><span style="color: #990000">)</span>
COMMIT
</tt></pre></div></div>
<div class="para"><p><tt>find_or_create</tt>'s sibling, <tt>find_or_initialize</tt>, will find an object and if it does not exist will call <tt>new</tt> with the parameters you passed in. For example:</p></div>
<div class="para"><p><tt>find_or_create</tt>'s sibling, <tt>find_or_initialize</tt>, will find an object and if it does not exist will act similar to calling <tt>new</tt> with the parameters you passed in. For example:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -951,7 +974,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> count<span style="color: #990000">(*)</span> <span style="font-weight: bold"><span style="color: #0000FF">AS</span></span> count_all <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>clients<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>first_name <span style="color: #990000">=</span> <span style="color: #993399">1</span><span style="color: #990000">)</span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> count<span style="color: #990000">(*)</span> <span style="font-weight: bold"><span style="color: #0000FF">AS</span></span> count_all <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span> <span style="color: #990000">(</span>first_name <span style="color: #990000">=</span> <span style="color: #993399">1</span><span style="color: #990000">)</span>
</tt></pre></div></div>
<div class="para"><p>You can also use <tt>include</tt> or <tt>joins</tt> for this to do something a little more complex:</p></div>
<div class="listingblock">
@ -967,8 +990,8 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> count<span style="color: #990000">(</span><span style="font-weight: bold"><span style="color: #0000FF">DISTINCT</span></span> <span style="color: #990000">+</span>clients<span style="color: #990000">+.</span>id<span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">AS</span></span> count_all <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> <span style="color: #990000">+</span>clients<span style="color: #990000">+</span>
<span style="font-weight: bold"><span style="color: #0000FF">LEFT</span></span> <span style="font-weight: bold"><span style="color: #0000FF">OUTER</span></span> <span style="font-weight: bold"><span style="color: #0000FF">JOIN</span></span> <span style="color: #990000">+</span>orders<span style="color: #990000">+</span> <span style="font-weight: bold"><span style="color: #0000FF">ON</span></span> orders<span style="color: #990000">.</span>client_id <span style="color: #990000">=</span> client<span style="color: #990000">.</span>id <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span>
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">SELECT</span></span> count<span style="color: #990000">(</span><span style="font-weight: bold"><span style="color: #0000FF">DISTINCT</span></span> clients<span style="color: #990000">.</span>id<span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">AS</span></span> count_all <span style="font-weight: bold"><span style="color: #0000FF">FROM</span></span> clients
<span style="font-weight: bold"><span style="color: #0000FF">LEFT</span></span> <span style="font-weight: bold"><span style="color: #0000FF">OUTER</span></span> <span style="font-weight: bold"><span style="color: #0000FF">JOIN</span></span> orders <span style="font-weight: bold"><span style="color: #0000FF">ON</span></span> orders<span style="color: #990000">.</span>client_id <span style="color: #990000">=</span> client<span style="color: #990000">.</span>id <span style="font-weight: bold"><span style="color: #0000FF">WHERE</span></span>
<span style="color: #990000">(</span>clients<span style="color: #990000">.</span>first_name <span style="color: #990000">=</span> <span style="color: #FF0000">'name'</span> <span style="font-weight: bold"><span style="color: #0000FF">AND</span></span> orders<span style="color: #990000">.</span><span style="font-weight: bold"><span style="color: #0000FF">status</span></span> <span style="color: #990000">=</span> <span style="color: #FF0000">'received'</span><span style="color: #990000">)</span>
</tt></pre></div></div>
<div class="para"><p>This code specifies <tt>clients.first_name</tt> just in case one of the join tables has a field also called <tt>first_name</tt> and it uses <tt>orders.status</tt> because that's the name of our join table.</p></div>
@ -1028,6 +1051,21 @@ http://www.gnu.org/software/src-highlite -->
<div class="ilist"><ul>
<li>
<p>
November 23 2008: Added documentation for <tt>find_by_last</tt> and <tt>find_by_bang!</tt>
</p>
</li>
<li>
<p>
November 21 2008: Fixed all points specified in <a href="http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16-activerecord-finders#ticket-16-13">this comment</a> and <a href="http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16-activerecord-finders#ticket-16-14">this comment</a>
</p>
</li>
<li>
<p>
November 18 2008: Fixed all points specified in <a href="http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16-activerecord-finders#ticket-16-11">this comment</a>
</p>
</li>
<li>
<p>
November 8, 2008: Editing pass by <a href="../authors.html#mgunderloy">Mike Gunderloy</a> . First release version.
</p>
</li>

View file

@ -566,6 +566,14 @@ http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>$ rails blog -d postgresql
</tt></pre></div></div>
<div class="para"><p>After you create the blog application, switch to its folder to continue work directly in that application:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>$ cd blog
</tt></pre></div></div>
<div class="para"><p>In any case, Rails will create a folder in your working directory called <tt>blog</tt>. Open up that folder and explore its contents. Most of the work in this tutorial will happen in the <tt>app/</tt> folder, but here's a basic rundown on the function of each folder that Rails creates in a new application by default:</p></div>
<div class="tableblock">
<table rules="all"
@ -764,6 +772,15 @@ http://www.gnu.org/software/src-highlite -->
password<span style="color: #990000">:</span>
</tt></pre></div></div>
<div class="para"><p>Change the username and password in the <tt>development</tt> section as appropriate.</p></div>
<h4 id="_creating_the_database">3.3.4. Creating the Database</h4>
<div class="para"><p>Now that you have your database configured, it's time to have Rails create an empty database for you. You can do this by running a rake command:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>$ rake db<span style="color: #990000">:</span>create
</tt></pre></div></div>
</div>
<h2 id="_hello_rails">4. Hello, Rails!</h2>
<div class="sectionbody">
@ -1031,7 +1048,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>If you were to translate that into words, it says something like: when this migration is run, create a table named <tt>posts</tt> with two string columns (<tt>name</tt> and <tt>title</tt>) and a text column (<tt>content</tt>), and generate timestamp fields to track record creation and updating. You can learn the detailed syntax for migrations in the <a href="../migrations.html">Rails Database Migrations</a> guide.</p></div>
<div class="para"><p>At this point, you need to do two things: create the database and run the migration. You can use rake commands at the terminal for both of those tasks:</p></div>
<div class="para"><p>At this point, you can use a rake command to run the migration:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@ -1045,7 +1062,7 @@ $ rake db<span style="color: #990000">:</span>migrate
<td class="icon">
<img src="./images/icons/note.png" alt="Note" />
</td>
<td class="content">Because you're working in the development environment by default, both of these commands will apply to the database defined in the <tt>development</tt> section of your <tt>config/database.yml</tt> file.</td>
<td class="content">Because you're working in the development environment by default, this command will apply to the database defined in the <tt>development</tt> section of your <tt>config/database.yml</tt> file.</td>
</tr></table>
</div>
<h3 id="_adding_a_link">6.2. Adding a Link</h3>
@ -1456,7 +1473,7 @@ http://www.gnu.org/software/src-highlite -->
<div class="sectionbody">
<div class="para"><p>At this point, its worth looking at some of the tools that Rails provides to eliminate duplication in your code. In particular, you can use <em>partials</em> to clean up duplication in views and <em>filters</em> to help with duplication in controllers.</p></div>
<h3 id="_using_partials_to_eliminate_view_duplication">7.1. Using Partials to Eliminate View Duplication</h3>
<div class="para"><p>As you saw earlier, the scaffold-generated views for the <tt>new</tt> and <tt>edit</tt> actions are largely identical. You can pull the shared code out into a <tt>partial</tt> template. This requires editing the new and edit views, and adding a new template:</p></div>
<div class="para"><p>As you saw earlier, the scaffold-generated views for the <tt>new</tt> and <tt>edit</tt> actions are largely identical. You can pull the shared code out into a <tt>partial</tt> template. This requires editing the new and edit views, and adding a new template. The new <tt>_form.html.erb</tt> template should be saved in the same <tt>app/views/posts</tt> folder as the files from which it is being extracted:</p></div>
<div class="para"><p><tt>new.html.erb</tt>:</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
@ -1791,7 +1808,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> show
<span style="color: #009900">@post</span> <span style="color: #990000">=</span> Post<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>post_id<span style="color: #990000">])</span>
<span style="color: #009900">@comment</span> <span style="color: #990000">=</span> Comment<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>id<span style="color: #990000">])</span>
<span style="color: #009900">@comment</span> <span style="color: #990000">=</span> <span style="color: #009900">@post</span><span style="color: #990000">.</span>comments<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>id<span style="color: #990000">])</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> new
@ -1803,7 +1820,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="color: #009900">@post</span> <span style="color: #990000">=</span> Post<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>post_id<span style="color: #990000">])</span>
<span style="color: #009900">@comment</span> <span style="color: #990000">=</span> <span style="color: #009900">@post</span><span style="color: #990000">.</span>comments<span style="color: #990000">.</span>build<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>comment<span style="color: #990000">])</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #009900">@comment</span><span style="color: #990000">.</span>save
redirect_to post_comment_path<span style="color: #990000">(</span><span style="color: #009900">@post</span><span style="color: #990000">,</span> <span style="color: #009900">@comment</span><span style="color: #990000">)</span>
redirect_to post_comment_url<span style="color: #990000">(</span><span style="color: #009900">@post</span><span style="color: #990000">,</span> <span style="color: #009900">@comment</span><span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">else</span></span>
render <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"new"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
@ -1811,14 +1828,14 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> edit
<span style="color: #009900">@post</span> <span style="color: #990000">=</span> Post<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>post_id<span style="color: #990000">])</span>
<span style="color: #009900">@comment</span> <span style="color: #990000">=</span> Comment<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>id<span style="color: #990000">])</span>
<span style="color: #009900">@comment</span> <span style="color: #990000">=</span> <span style="color: #009900">@post</span><span style="color: #990000">.</span>comments<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>id<span style="color: #990000">])</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> update
<span style="color: #009900">@post</span> <span style="color: #990000">=</span> Post<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>post_id<span style="color: #990000">])</span>
<span style="color: #009900">@comment</span> <span style="color: #990000">=</span> Comment<span style="color: #990000">.</span>find<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>id<span style="color: #990000">])</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #009900">@comment</span><span style="color: #990000">.</span>update_attributes<span style="color: #990000">(</span>params<span style="color: #990000">[:</span>comment<span style="color: #990000">])</span>
redirect_to post_comment_path<span style="color: #990000">(</span><span style="color: #009900">@post</span><span style="color: #990000">,</span> <span style="color: #009900">@comment</span><span style="color: #990000">)</span>
redirect_to post_comment_url<span style="color: #990000">(</span><span style="color: #009900">@post</span><span style="color: #990000">,</span> <span style="color: #009900">@comment</span><span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #0000FF">else</span></span>
render <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"edit"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
@ -1990,7 +2007,7 @@ http://www.gnu.org/software/src-highlite -->
<div class="ilist"><ul>
<li>
<p>
The <a href="http://manuals.rubyonrails.org/">Ruby On Rails guides</a>
The <a href="http://guides.rubyonrails.org/">Ruby On Rails guides</a>
</p>
</li>
<li>

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@ -338,6 +338,19 @@ of your code.</p></div>
<div class="sidebar-title"><a href="creating_plugins.html">The Basics of Creating Rails Plugins</a></div>
<div class="para"><p>This guide covers how to build a plugin to extend the functionality of Rails.</p></div>
</div></div>
<div class="sidebarblock">
<div class="sidebar-content">
<div class="sidebar-title"><a href="i18n.html">The Rails Internationalization API</a></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<img src="./images/icons/caution.png" alt="Caution" />
</td>
<td class="content">still a basic draft</td>
</tr></table>
</div>
<div class="para"><p>This guide introduces you to the basic concepts and features of the Rails I18n API and shows you how to localize your application.</p></div>
</div></div>
<div class="para"><p>Authors who have contributed to complete guides are listed <a href="authors.html">here</a>.</p></div>
<div class="para"><p>This work is licensed under a <a href="http://creativecommons.org/licenses/by-nc-sa/3.0/">Creative Commons Attribution-Noncommercial-Share Alike 3.0 License</a></p></div>
</div>

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@ -279,7 +279,7 @@ ul#navMain {
<h1>Migrations</h1>
<div id="preamble">
<div class="sectionbody">
<div class="para"><p>Migrations are a convenient way for you to alter your database in a structured and organised manner. You could edit fragments of SQL by hand but you would then be responsible for telling other developers that they need to go and run it. You'd also have to keep track of which changes need to be run against the production machines next time you deploy. Active Record tracks which migrations have already been run so all you have to do is update your source and run <tt>rake db:migrate</tt>. Active Record will work out which migrations should be run.</p></div>
<div class="para"><p>Migrations are a convenient way for you to alter your database in a structured and organised manner. You could edit fragments of SQL by hand but you would then be responsible for telling other developers that they need to go and run it. You'd also have to keep track of which changes need to be run against the production machines next time you deploy. Active Record tracks which migrations have already been run so all you have to do is update your source and run <tt>rake db:migrate</tt>. Active Record will work out which migrations should be run. It will also update your db/schema.rb file to match the structure of your database.</p></div>
<div class="para"><p>Migrations also allow you to describe these transformations using Ruby. The great thing about this is that (like most of Active Record's functionality) it is database independent: you don't need to worry about the precise syntax of CREATE TABLE any more that you worry about variations on SELECT * (you can drop down to raw SQL for database specific features). For example you could use SQLite3 in development, but MySQL in production.</p></div>
<div class="para"><p>You'll learn all about migrations including:</p></div>
<div class="ilist"><ul>
@ -699,6 +699,7 @@ displayed saying that it can't be done.</p></div>
<h2 id="_running_migrations">4. Running Migrations</h2>
<div class="sectionbody">
<div class="para"><p>Rails provides a set of rake tasks to work with migrations which boils down to running certain sets of migrations. The very first migration related rake task you use will probably be <tt>db:migrate</tt>. In its most basic form it just runs the <tt>up</tt> method for all the migrations that have not yet been run. If there are no such migrations it exits.</p></div>
<div class="para"><p>Note that running the <tt>db:migrate</tt> also invokes the <tt>db:schema:dump</tt> task, which will update your db/schema.rb file to match the structure of your database.</p></div>
<div class="para"><p>If you specify a target version, Active Record will run the required migrations (up or down) until it has reached the specified version. The
version is the numerical prefix on the migration's filename. For example to migrate to version 20080906120000 run</p></div>
<div class="listingblock">

View file

@ -1454,7 +1454,7 @@ http://www.gnu.org/software/src-highlite -->
<td class="icon">
<img src="./images/icons/tip.png" alt="Tip" />
</td>
<td class="content">If your application has many RESTful routes, using <tt>:only</tt> and <tt>:accept</tt> to generate only the routes that you actually need can cut down on memory use and speed up the routing process.</td>
<td class="content">If your application has many RESTful routes, using <tt>:only</tt> and <tt>:except</tt> to generate only the routes that you actually need can cut down on memory use and speed up the routing process.</td>
</tr></table>
</div>
<h3 id="_nested_resources">3.8. Nested Resources</h3>
@ -1905,7 +1905,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>map<span style="color: #990000">.</span>connect <span style="color: #FF0000">'photo/:id'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'photos'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'show'</span>
<pre><tt>map<span style="color: #990000">.</span>connect <span style="color: #FF0000">'photos/:id'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'photos'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'show'</span>
</tt></pre></div></div>
<div class="para"><p>With this route, an incoming URL of <tt>/photos/12</tt> would be dispatched to the <tt>show</tt> action within the <tt>Photos</tt> controller.</p></div>
<div class="para"><p>You an also define other defaults in a route by supplying a hash for the <tt>:defaults</tt> option. This even applies to parameters that are not explicitly defined elsewhere in the route. For example:</p></div>
@ -1914,7 +1914,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>map<span style="color: #990000">.</span>connect <span style="color: #FF0000">'photo/:id'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'photos'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'show'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>defaults <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">{</span> <span style="color: #990000">:</span>format <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'jpg'</span> <span style="color: #FF0000">}</span>
<pre><tt>map<span style="color: #990000">.</span>connect <span style="color: #FF0000">'photos/:id'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'photos'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'show'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>defaults <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">{</span> <span style="color: #990000">:</span>format <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">'jpg'</span> <span style="color: #FF0000">}</span>
</tt></pre></div></div>
<div class="para"><p>With this route, an incoming URL of <tt>photos/12</tt> would be dispatched to the <tt>show</tt> action within the <tt>Photos</tt> controller, and <tt>params[:format]</tt> will be set to <tt>jpg</tt>.</p></div>
<h3 id="_named_routes_2">4.6. Named Routes</h3>
@ -2056,7 +2056,7 @@ http://www.gnu.org/software/src-highlite -->
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt>map<span style="color: #990000">.</span>index <span style="color: #990000">:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"pages"</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"main"</span>
<pre><tt>map<span style="color: #990000">.</span>index <span style="color: #FF0000">'index'</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>controller <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"pages"</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>action <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"main"</span>
map<span style="color: #990000">.</span>root <span style="color: #990000">:</span>index
</tt></pre></div></div>
<div class="para"><p>Because of the top-down processing of the file, the named route must be specified <em>before</em> the call to <tt>map.root</tt>.</p></div>

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@ -265,7 +265,7 @@ map.resources :products, :except => :destroy
=== Other Action Controller Changes
* You can now easily link:http://m.onkey.org/2008/7/20/rescue-from-dispatching[show a custom error page] for exceptions raised while routing a request.
* The HTTP Accept header is disabled by default now. You should prefer the use of formatted URLs (such as +/customers/1.xml+) to indicate the format that you want. If you need the Accept headers, you can turn them back on with +config.action_controller.user_accept_header = true+.
* The HTTP Accept header is disabled by default now. You should prefer the use of formatted URLs (such as +/customers/1.xml+) to indicate the format that you want. If you need the Accept headers, you can turn them back on with +config.action_controller.use_accept_header = true+.
* Benchmarking numbers are now reported in milliseconds rather than tiny fractions of seconds
* Rails now supports HTTP-only cookies (and uses them for sessions), which help mitigate some cross-site scripting risks in newer browsers.
* +redirect_to+ now fully supports URI schemes (so, for example, you can redirect to a svn+ssh: URI).
@ -365,11 +365,11 @@ Lead Contributor: link:http://workingwithrails.com/person/5830-daniel-schierbeck
* Extensive updates to +ActiveSupport::Multibyte+, including Ruby 1.9 compatibility fixes.
* The addition of +ActiveSupport::Rescuable+ allows any class to mix in the +rescue_from+ syntax.
* +past?+, +today?+ and +future?+ for +Date+ and +Time+ classes to facilitate date/time comparisons.
* +Array#second+ through +Array#tenth+ as aliases for +Array#[1]+ through +Array#[9]+
* +Array#second+ through +Array#fifth+ as aliases for +Array#[1]+ through +Array#[4]+
* +Enumerable#many?+ to encapsulate +collection.size > 1+
* +Inflector#parameterize+ produces a URL-ready version of its input, for use in +to_param+.
* +Time#advance+ recognizes fractional days and weeks, so you can do +1.7.weeks.ago+, +1.5.hours.since+, and so on.
* The included TzInfo library has been upgraded to version 0.3.11.
* The included TzInfo library has been upgraded to version 0.3.12.
* +ActiveSuport::StringInquirer+ gives you a pretty way to test for equality in strings: +ActiveSupport::StringInquirer.new("abc").abc? => true+
== Railties
@ -381,7 +381,7 @@ In Railties (the core code of Rails itself) the biggest changes are in the +conf
To avoid deployment issues and make Rails applications more self-contained, it's possible to place copies of all of the gems that your Rails application requires in +/vendor/gems+. This capability first appeared in Rails 2.1, but it's much more flexible and robust in Rails 2.2, handling complicated dependencies between gems. Gem management in Rails includes these commands:
* +config.gem _gem_name_+ in your +config/environment.rb+ file
* +rake gems+ to list all configured gems, as well as whether they (and their dependencies) are installed or frozen
* +rake gems+ to list all configured gems, as well as whether they (and their dependencies) are installed, frozen, or framework (framework gems are those loaded by Rails before the gem dependency code is executed; such gems cannot be frozen)
* +rake gems:install+ to install missing gems to the computer
* +rake gems:unpack+ to place a copy of the required gems into +/vendor/gems+
* +rake gems:unpack:dependencies+ to get copies of the required gems and their dependencies into +/vendor/gems+
@ -394,6 +394,7 @@ You can unpack or install a single gem by specifying +GEM=_gem_name_+ on the com
* More information:
- link:http://ryandaigle.com/articles/2008/4/1/what-s-new-in-edge-rails-gem-dependencies[What's New in Edge Rails: Gem Dependencies]
- link:http://afreshcup.com/2008/10/25/rails-212-and-22rc1-update-your-rubygems/[Rails 2.1.2 and 2.2RC1: Update Your RubyGems]
- link:http://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/1128[Detailed discussion on Lighthouse]
=== Other Railties Changes

View file

@ -31,4 +31,4 @@ class CommentsController < ApplicationController
end
-----------------------------------------
Note that while for session values, you set the key to `nil`, to delete a cookie value, you should use `cookies.delete(:key)`.
Note that while for session values you set the key to `nil`, to delete a cookie value you should use `cookies.delete(:key)`.

View file

@ -38,7 +38,7 @@ class ApplicationController < ActionController::Base
end
---------------------------------
In this example, the filter is added to ApplicationController and thus all controllers in the application. This will make everything in the application require the user to be logged in in order to use it. For obvious reasons (the user wouldn't be able to log in in the first place!), not all controllers or actions should require this. You can prevent this filter from running before particular actions with `skip_before_filter` :
In this example, the filter is added to ApplicationController and thus all controllers in the application. This will make everything in the application require the user to be logged in in order to use it. For obvious reasons (the user wouldn't be able to log in in the first place!), not all controllers or actions should require this. You can prevent this filter from running before particular actions with `skip_before_filter`:
[source, ruby]
---------------------------------
@ -49,7 +49,7 @@ class LoginsController < Application
end
---------------------------------
Now, the +LoginsController+'s "new" and "create" actions will work as before without requiring the user to be logged in. The `:only` option is used to only skip this filter for these actions, and there is also an `:except` option which works the other way. These options can be used when adding filters too, so you can add a filter which only runs for selected actions in the first place.
Now, the LoginsController's `new` and `create` actions will work as before without requiring the user to be logged in. The `:only` option is used to only skip this filter for these actions, and there is also an `:except` option which works the other way. These options can be used when adding filters too, so you can add a filter which only runs for selected actions in the first place.
=== After Filters and Around Filters ===

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@ -1,6 +1,6 @@
== Parameter Filtering ==
Rails keeps a log file for each environment (development, test and production) in the "log" folder. These are extremely useful when debugging what's actually going on in your application, but in a live application you may not want every bit of information to be stored in the log file. The `filter_parameter_logging` method can be used to filter out sensitive information from the log. It works by replacing certain values in the `params` hash with "[FILTERED]" as they are written to the log. As an example, let's see how to filter all parameters with keys that include "password":
Rails keeps a log file for each environment (development, test and production) in the `log` folder. These are extremely useful when debugging what's actually going on in your application, but in a live application you may not want every bit of information to be stored in the log file. The `filter_parameter_logging` method can be used to filter out sensitive information from the log. It works by replacing certain values in the `params` hash with "[FILTERED]" as they are written to the log. As an example, let's see how to filter all parameters with keys that include "password":
[source, ruby]
-------------------------
@ -11,4 +11,4 @@ class ApplicationController < ActionController::Base
end
-------------------------
The method works recursively through all levels of the params hash and takes an optional second parameter which is used as the replacement string if present. It can also take a block which receives each key in return and replaces those for which the block returns true.
The method works recursively through all levels of the params hash and takes an optional second parameter which is used as the replacement string if present. It can also take a block which receives each key in turn and replaces those for which the block returns true.

View file

@ -7,13 +7,13 @@ In every controller there are two accessor methods pointing to the request and t
The request object contains a lot of useful information about the request coming in from the client. To get a full list of the available methods, refer to the link:http://api.rubyonrails.org/classes/ActionController/AbstractRequest.html[API documentation]. Among the properties that you can access on this object are:
* host - The hostname used for this request.
* domain - The hostname without the first segment (usually "www").
* domain(n=2) - The hostname's first `n` segments, starting from the right (the TLD)
* format - The content type requested by the client.
* method - The HTTP method used for the request.
* get?, post?, put?, delete?, head? - Returns true if the HTTP method is get/post/put/delete/head.
* get?, post?, put?, delete?, head? - Returns true if the HTTP method is GET/POST/PUT/DELETE/HEAD.
* headers - Returns a hash containing the headers associated with the request.
* port - The port number (integer) used for the request.
* protocol - The protocol used for the request.
* protocol - Returns a string containing the prototol used plus "://", for example "http://"
* query_string - The query string part of the URL - everything after "?".
* remote_ip - The IP address of the client.
* url - The entire URL used for the request.

View file

@ -52,7 +52,7 @@ This will read and stream the file 4Kb at the time, avoiding loading the entire
WARNING: Be careful when using (or just don't use) "outside" data (params, cookies, etc) to locate the file on disk, as this is a security risk that might allow someone to gain access to files they are not meant to see.
TIP: It is not recommended that you stream static files through Rails if you can instead keep them in a public folder on your web server. It is much more efficient to let the user download the file directly using Apache or another web server, keeping the request from unnecessarily going through the whole Rails stack.
TIP: It is not recommended that you stream static files through Rails if you can instead keep them in a public folder on your web server. It is much more efficient to let the user download the file directly using Apache or another web server, keeping the request from unnecessarily going through the whole Rails stack. Although if you do need the request to go through Rails for some reason, you can set the `:x_sendfile` option to true, and Rails will let the web server handle sending the file to the user, freeing up the Rails process to do other things. Note that your web server needs to support the `X-Sendfile` header for this to work, and you still have to be careful not to use user input in a way that lets someone retrieve arbitrary files.
=== RESTful Downloads ===

View file

@ -25,7 +25,7 @@ class LoginsController < ApplicationController
end
---------------------------------------
Now the `create` action won't run unless the "username" and "password" parameters are present, and if they're not, an error message will be added to the flash and the "new" action will be rendered. But there's something rather important missing from the verification above: It will be used for *every* action in LoginsController, which is not what we want. You can limit which actions it will be used for with the `:only` and `:except` options just like a filter:
Now the `create` action won't run unless the "username" and "password" parameters are present, and if they're not, an error message will be added to the flash and the `new` action will be rendered. But there's something rather important missing from the verification above: It will be used for *every* action in LoginsController, which is not what we want. You can limit which actions it will be used for with the `:only` and `:except` options just like a filter:
[source, ruby]
---------------------------------------

View file

@ -7,7 +7,7 @@ After reading this guide and trying out the presented concepts, we hope that you
* Correctly use all the built-in Active Record validation helpers
* Create your own custom validation methods
* Work with the error messages generated by the validation proccess
* Work with the error messages generated by the validation process
* Register callback methods that will execute custom operations during your objects lifecycle, for example before/after they are saved.
* Create special classes that encapsulate common behaviour for your callbacks
* Create Observers - classes with callback methods specific for each of your models, keeping the callback code outside your models' declarations.
@ -47,7 +47,9 @@ We can see how it works by looking at the following script/console output:
=> false
------------------------------------------------------------------
Saving new records means sending an SQL insert operation to the database, while saving existing records (by calling either +save+, +update_attribute+ or +update_attributes+) will result in a SQL update operation. Active Record will use this facts to perform validations upon your objects, avoiding then to be recorded to the database if their inner state is invalid in some way. You can specify validations that will be beformed every time a object is saved, just when you're creating a new record or when you're updating an existing one.
Saving new records means sending an SQL insert operation to the database, while saving existing records (by calling either +save+ or +update_attributes+) will result in a SQL update operation. Active Record will use this facts to perform validations upon your objects, avoiding then to be recorded to the database if their inner state is invalid in some way. You can specify validations that will be beformed every time a object is saved, just when you're creating a new record or when you're updating an existing one.
CAUTION: There are four methods that when called will trigger validation: +save+, +save!+, +update_attributes+ and +update_attributes!+. There is one method left, which is +update_attribute+. This method will update the value of an attribute without triggering any validation, so be careful when using +update_attribute+, since it can let you save your objects in an invalid state.
=== The meaning of 'valid'
@ -301,7 +303,7 @@ There are some common options that all the validation helpers can use. Here they
=== The +:allow_nil+ option
You may use the +:allow_nil+ option everytime you just want to trigger a validation if the value being validated is not +nil+. You may be asking yourself if it makes any sense to use +:allow_nil+ and +validates_presence_of+ together. Well, it does. Remember, validation will be skipped only for +nil+ attributes, but empty strings are not considered +nil+.
You may use the +:allow_nil+ option everytime you want to trigger a validation only if the value being validated is not +nil+. You may be asking yourself if it makes any sense to use +:allow_nil+ and +validates_presence_of+ together. Well, it does. Remember, validation will be skipped only for +nil+ attributes, but empty strings are not considered +nil+.
[source, ruby]
------------------------------------------------------------------
@ -382,7 +384,7 @@ class Invoice < ActiveRecord::Base
end
------------------------------------------------------------------
If your validation rules are too complicated and you want to break it in small methods, you can implement all of them and call one of +validate+, +validate_on_create+ or +validate_on_update+ methods, passing it the symbols for the methods' names.
If your validation rules are too complicated and you want to break them in small methods, you can implement all of them and call one of +validate+, +validate_on_create+ or +validate_on_update+ methods, passing it the symbols for the methods' names.
[source, ruby]
------------------------------------------------------------------
@ -399,6 +401,284 @@ class Invoice < ActiveRecord::Base
end
------------------------------------------------------------------
== Using the +errors+ collection
You can do more than just call +valid?+ upon your objects based on the existance of the +errors+ collection. Here is a list of the other available methods that you can use to manipulate errors or ask for an object's state.
* +add_to_base+ lets you add errors messages that are related to the object's state as a whole, instead of being related to a specific attribute. You can use this method when you want to say that the object is invalid, no matter the values of it's attributes. +add_to_base+ receives a string with the message.
[source, ruby]
------------------------------------------------------------------
class Person < ActiveRecord::Base
def a_method_used_for_validation_purposes
errors.add_to_base("This person is invalid because ...")
end
end
------------------------------------------------------------------
* +add+ lets you manually add messages that are related to particular attributes. When writing those messages, keep in mind that Rails will prepend them with the name of the attribute that holds the error, so write it in a way that makes sense. +add+ receives a symbol with the name of the attribute that you want to add the message to and the message itself.
[source, ruby]
------------------------------------------------------------------
class Person < ActiveRecord::Base
def a_method_used_for_validation_purposes
errors.add(:name, "can't have the characters !@#$%*()_-+=")
end
end
------------------------------------------------------------------
* +invalid?+ is used when you want to check if a particular attribute is invalid. It receives a symbol with the name of the attribute that you want to check.
[source, ruby]
------------------------------------------------------------------
class Person < ActiveRecord::Base
validates_presence_of :name, :email
end
person = Person.new(:name => "John Doe")
person.invalid?(:email) # => true
------------------------------------------------------------------
* +on+ is used when you want to check the error messages for a specific attribute. It will return different kinds of objects depending on the state of the +errors+ collection for the given attribute. If there are no errors related to the attribute, +on+ will return +nil+. If there is just one errors message for this attribute, +on+ will return a string with the message. When +errors+ holds two or more error messages for the attribute, +on+ will return an array of strings, each one with one error message.
[source, ruby]
------------------------------------------------------------------
class Person < ActiveRecord::Base
validates_presence_of :name
validates_length_of :name, :minimum => 3
end
person = Person.new(:name => "John Doe")
person.valid? # => true
person.errors.on(:name) # => nil
person = Person.new(:name => "JD")
person.valid? # => false
person.errors.on(:name) # => "is too short (minimum is 3 characters)"
person = Person.new
person.valid? # => false
person.errors.on(:name) # => ["can't be blank", "is too short (minimum is 3 characters)"]
------------------------------------------------------------------
* +clear+ is used when you intentionally wants to clear all the messages in the +errors+ collection.
[source, ruby]
------------------------------------------------------------------
class Person < ActiveRecord::Base
validates_presence_of :name
validates_length_of :name, :minimum => 3
end
person = Person.new
puts person.valid? # => false
person.errors.on(:name) # => ["can't be blank", "is too short (minimum is 3 characters)"]
person.errors.clear
person.errors # => nil
------------------------------------------------------------------
== Callbacks
Callbacks are methods that get called at certain moments of an object's lifecycle. With callbacks it's possible to write code that will run whenever an Active Record object is created, saved, updated, deleted or loaded from the database.
=== Callbacks registration
In order to use the available callbacks, you need to registrate them. There are two ways of doing that.
=== Registering callbacks by overriding the callback methods
You can specify the callback method directly, by overriding it. Let's see how it works using the +before_validation+ callback, which will surprisingly run right before any validation is done.
[source, ruby]
------------------------------------------------------------------
class User < ActiveRecord::Base
validates_presence_of :login, :email
protected
def before_validation
if self.login.nil?
self.login = email unless email.blank?
end
end
end
------------------------------------------------------------------
=== Registering callbacks by using macro-style class methods
The other way you can register a callback method is by implementing it as an ordinary method, and then using a macro-style class method to register it as a callback. The last example could be written like that:
[source, ruby]
------------------------------------------------------------------
class User < ActiveRecord::Base
validates_presence_of :login, :email
before_validation :ensure_login_has_a_value
protected
def ensure_login_has_a_value
if self.login.nil?
self.login = email unless email.blank?
end
end
end
------------------------------------------------------------------
The macro-style class methods can also receive a block. Rails best practices say that you should only use this style of registration if the code inside your block is so short that it fits in just one line.
[source, ruby]
------------------------------------------------------------------
class User < ActiveRecord::Base
validates_presence_of :login, :email
before_create {|user| user.name = user.login.capitalize if user.name.blank?}
end
------------------------------------------------------------------
In Rails, the preferred way of registering callbacks is by using macro-style class methods. The main advantages of using macro-style class methods are:
* You can add more than one method for each type of callback. Those methods will be queued for execution at the same order they were registered.
* Readability, since your callback declarations will live at the beggining of your models' files.
CAUTION: Remember to always declare the callback methods as being protected or private. These methods should never be public, otherwise it will be possible to call them from code outside the model, violating object encapsulation and exposing implementation details.
== Available callbacks
Here is a list with all the available Active Record callbacks, listed in the same order in which they will get called during the respective operations.
=== Callbacks called both when creating or updating a record.
* +before_validation+
* +after_validation+
* +before_save+
* *INSERT OR UPDATE OPERATION*
* +after_save+
=== Callbacks called only when creating a new record.
* +before_validation_on_create+
* +after_validation_on_create+
* +before_create+
* *INSERT OPERATION*
* +after_create+
=== Callbacks called only when updating an existing record.
* +before_validation_on_update+
* +after_validation_on_update+
* +before_update+
* *UPDATE OPERATION*
* +after_update+
=== Callbacks called when removing a record from the database.
* +before_destroy+
* *DELETE OPERATION*
* +after_destroy+
The +before_destroy+ and +after_destroy+ callbacks will only be called if you delete the model using either the +destroy+ instance method or one of the +destroy+ or +destroy_all+ class methods of your Active Record class. If you use +delete+ or +delete_all+ no callback operations will run, since Active Record will not instantiate any objects, accessing the records to be deleted directly in the database.
=== The +after_initialize+ and +after_find+ callbacks
The +after_initialize+ callback will be called whenever an Active Record object is instantiated, either by direcly using +new+ or when a record is loaded from the database. It can be useful to avoid the need to directly override your Active Record +initialize+ method.
The +after_find+ callback will be called whenever Active Record loads a record from the database. When used together with +after_initialize+ it will run first, since Active Record will first read the record from the database and them create the model object that will hold it.
The +after_initialize+ and +after_find+ callbacks are a bit different from the others, since the only way to register those callbacks is by defining them as methods. If you try to register +after_initialize+ or +after_find+ using macro-style class methods, they will just be ignored. This behaviour is due to performance reasons, since +after_initialize+ and +after_find+ will both be called for each record found in the database, significantly slowing down the queries.
== Halting Execution
As you start registering new callbacks for your models, they will be queued for execution. This queue will include all your model's validations, the registered callbacks and the database operation to be executed. However, if at any moment one of the callback methods returns a boolean +false+ (not +nil+) value, this execution chain will be halted and the desired operation will not complete: your model will not get persisted in the database, or your records will not get deleted and so on.
== Callback classes
Sometimes the callback methods that you'll write will be useful enough to be reused at other models. Active Record makes it possible to create classes that encapsulate the callback methods, so it becomes very easy to reuse them.
Here's an example where we create a class with a after_destroy callback for a PictureFile model.
[source, ruby]
------------------------------------------------------------------
class PictureFileCallbacks
def after_destroy(picture_file)
File.delete(picture_file.filepath) if File.exists?(picture_file.filepath)
end
end
------------------------------------------------------------------
When declared inside a class the callback method will receive the model object as a parameter. We can now use it this way:
[source, ruby]
------------------------------------------------------------------
class PictureFile < ActiveRecord::Base
after_destroy PictureFileCallbacks.new
end
------------------------------------------------------------------
Note that we needed to instantiate a new PictureFileCallbacks object, since we declared our callback as an instance method. Sometimes it will make more sense to have it as a class method.
[source, ruby]
------------------------------------------------------------------
class PictureFileCallbacks
def self.after_destroy(picture_file)
File.delete(picture_file.filepath) if File.exists?(picture_file.filepath)
end
end
------------------------------------------------------------------
If the callback method is declared this way, it won't be necessary to instantiate a PictureFileCallbacks object.
[source, ruby]
------------------------------------------------------------------
class PictureFile < ActiveRecord::Base
after_destroy PictureFileCallbacks
end
------------------------------------------------------------------
You can declare as many callbacks as you want inside your callback classes.
== Observers
Active Record callbacks are a powerful feature, but they can pollute your model implementation with code that's not directly related to the model's purpose. In object-oriented software, it's always a good idea to design your classes with a single responsability in the whole system. For example, it wouldn't make much sense to have a +User+ model with a method that writes data about a login attempt to a log file. Whenever you're using callbacks to write code that's not directly related to your model class purposes, it may be a good moment to create an Observer.
An Active Record Observer is an object that links itself to a model and register it's methods for callbacks. Your model's implementation remain clean, while you can reuse the code in the Observer to add behaviuor to more than one model class. Ok, you may say that we can also do that using callback classes, but it would still force us to add code to our model's implementation.
Observer classes are subclasses of the +ActiveRecord::Observer+ class. When this class is subclassed, Active Record will look at the name of the new class and then strip the 'Observer' part to find the name of the Active Record class to observe.
Consider a +Registration+ model, where we want to send an email everytime a new registration is created. Since sending emails is not directly related to our model's purpose, we could create an Observer to do just that:
[source, ruby]
------------------------------------------------------------------
class RegistrationObserver < ActiveRecord::Observer
def after_create(model)
# code to send registration confirmation emails...
end
end
------------------------------------------------------------------
Like in callback classes, the observer's methods receive the observed model as a parameter.
Sometimes using the ModelName + Observer naming convention won't be the best choice, mainly when you want to use the same observer for more than one model class. It's possible to explicity specify the models that our observer should observe.
[source, ruby]
------------------------------------------------------------------
class Auditor < ActiveRecord::Observer
observe User, Registration, Invoice
end
------------------------------------------------------------------
=== Registering observers
If you payed attention, you may be wondering where Active Record Observers are referenced in our applications, so they get instantiate and begin to interact with our models. For observers to work we need to register then in our application's *config/environment.rb* file. In this file there is a commented out line where we can define the observers that our application should load at start-up.
[source, ruby]
------------------------------------------------------------------
# Activate observers that should always be running
config.active_record.observers = :registration_observer, :auditor
------------------------------------------------------------------
=== Where to put the observers' source files
By convention, you should always save your observers' source files inside *app/models*.
== Changelog
http://rails.lighthouseapp.com/projects/16213/tickets/26-active-record-validations-and-callbacks

View file

@ -354,8 +354,8 @@ In designing a data model, you will sometimes find a model that should have a re
[source, ruby]
-------------------------------------------------------
class Employee < ActiveRecord::Base
has_many :subordinates, :class_name => "User", :foreign_key => "manager_id"
belongs_to :manager, :class_name => "User"
has_many :subordinates, :class_name => "Employee", :foreign_key => "manager_id"
belongs_to :manager, :class_name => "Employee"
end
-------------------------------------------------------
@ -396,7 +396,11 @@ You are not free to use just any name for your associations. Because creating an
=== Updating the Schema
Associations are extremely useful, but they are not magic. You are responsible for maintaining your database schema to match your associations. In practice, this means two things. First, you need to create foreign keys as appropriate:
Associations are extremely useful, but they are not magic. You are responsible for maintaining your database schema to match your associations. In practice, this means two things, depending on what sort of associations you are creating. For +belongs_to+ associations you need to create foreign keys, and for +has_and_belongs_to_many+ associations you need to create the appropriate join table.
==== Creating Foreign Keys for +belongs_to+ Associations
When you declare a +belongs_to+ association, you need to create foreign keys as appropriate. For example, consider this model:
[source, ruby]
-------------------------------------------------------
@ -412,9 +416,9 @@ This declaration needs to be backed up by the proper foreign key declaration on
class CreateOrders < ActiveRecord::Migration
def self.up
create_table :orders do |t|
t.order_date :datetime
t.order_number :string
t.customer_id :integer
t.datetime :order_date
t.string :order_number
t.integer :customer_id
end
end
@ -426,7 +430,9 @@ end
If you create an association some time after you build the underlying model, you need to remember to create an +add_column+ migration to provide the necessary foreign key.
Second, if you create a +has_and_belongs_to_many+ association, you need to explicitly create the joining table. Unless the name of the join table is explicitly specified by using the +:join_table+ option, Active Record create the name by using the lexical order of the class names. So a join between customer and order models will give the default join table name of "customers_orders" because "c" outranks "o" in lexical ordering.
==== Creating Join Tables for +has_and_belongs_to_many+ Associations
If you create a +has_and_belongs_to_many+ association, you need to explicitly create the joining table. Unless the name of the join table is explicitly specified by using the +:join_table+ option, Active Record create the name by using the lexical order of the class names. So a join between customer and order models will give the default join table name of "customers_orders" because "c" outranks "o" in lexical ordering.
WARNING: The precedence between model names is calculated using the +<+ operator for +String+. This means that if the strings are of different lengths, and the strings are equal when compared up to the shortest length, then the longer string is considered of higher lexical precedence than the shorter one. For example, one would expect the tables "paper_boxes" and "papers" to generate a join table name of "papers_paper_boxes" because of the length of the name "paper_boxes", but it in fact generates a join table name of "paper_boxes_papers".
@ -1330,7 +1336,7 @@ end
===== +:offset+
The +:offset+ option lets you specify the starting offset for fetching objects via an association. For example, if you set +:offset => 11+, it will skip the first 10 records.
The +:offset+ option lets you specify the starting offset for fetching objects via an association. For example, if you set +:offset => 11+, it will skip the first 11 records.
===== +:order+
@ -1698,7 +1704,7 @@ end
===== +:offset+
The +:offset+ option lets you specify the starting offset for fetching objects via an association. For example, if you set +:offset => 11+, it will skip the first 10 records.
The +:offset+ option lets you specify the starting offset for fetching objects via an association. For example, if you set +:offset => 11+, it will skip the first 11 records.
===== +:order+

View file

@ -37,3 +37,9 @@ Heiko has rarely looked back.
Tore Darell is an independent developer based in Menton, France who specialises in cruft-free web applications using Ruby, Rails
and unobtrusive JavaScript. His home on the internet is his blog http://tore.darell.no/[Sneaky Abstractions].
***********************************************************
.Jeff Dean
[[zilkey]]
***********************************************************
Jeff Dean is a software engineer with http://pivotallabs.com/[Pivotal Labs].
***********************************************************

View file

@ -10,8 +10,8 @@ need to return to those hungry web clients in the shortest time possible.
This is an introduction to the three types of caching techniques that Rails
provides by default without the use of any third party plugins.
To get started make sure config.action_controller.perform_caching is set
to true for your environment. This flag is normally set in the
To get started make sure `config.action_controller.perform_caching` is set
to `true` for your environment. This flag is normally set in the
corresponding config/environments/*.rb and caching is disabled by default
there for development and test, and enabled for production.
@ -45,21 +45,21 @@ end
-----------------------------------------------------
The first time anyone requests products/index, Rails will generate a file
called index.html and the webserver will then look for that file before it
called `index.html` and the webserver will then look for that file before it
passes the next request for products/index to your Rails application.
By default, the page cache directory is set to Rails.public_path (which is
usually set to RAILS_ROOT + "/public") and this can be configured by
changing the configuration setting ActionController::Base.page_cache_directory. Changing the
default from /public helps avoid naming conflicts, since you may want to
put other static html in /public, but changing this will require web
server reconfiguration to let the web server know where to serve the
cached files from.
usually set to `RAILS_ROOT + "/public"`) and this can be configured by
changing the configuration setting `config.action_controller.page_cache_directory`.
Changing the default from /public helps avoid naming conflicts, since you may
want to put other static html in /public, but changing this will require web
server reconfiguration to let the web server know where to serve the cached
files from.
The Page Caching mechanism will automatically add a .html exxtension to
The Page Caching mechanism will automatically add a `.html` exxtension to
requests for pages that do not have an extension to make it easy for the
webserver to find those pages and this can be configured by changing the
configuration setting ActionController::Base.page_cache_extension.
configuration setting `config.action_controller.page_cache_extension`.
In order to expire this page when a new product is added we could extend our
example controler like this:
@ -119,8 +119,8 @@ class ProductsController < ActionController
end
-----------------------------------------------------
And you can also use :if (or :unless) to pass a Proc that specifies when the
action should be cached. Also, you can use :layout => false to cache without
And you can also use `:if` (or `:unless`) to pass a Proc that specifies when the
action should be cached. Also, you can use `:layout => false` to cache without
layout so that dynamic information in the layout such as logged in user info
or the number of items in the cart can be left uncached. This feature is
available as of Rails 2.2.
@ -164,7 +164,7 @@ could use this piece of code:
The cache block in our example will bind to the action that called it and is
written out to the same place as the Action Cache, which means that if you
want to cache multiple fragments per action, you should provide an action_suffix to the cache call:
want to cache multiple fragments per action, you should provide an `action_suffix` to the cache call:
[source, ruby]
-----------------------------------------------------
@ -172,11 +172,29 @@ want to cache multiple fragments per action, you should provide an action_suffix
All available products:
-----------------------------------------------------
and you can expire it using the expire_fragment method, like so:
and you can expire it using the `expire_fragment` method, like so:
[source, ruby]
-----------------------------------------------------
expire_fragment(:controller => 'producst', :action => 'recent', :action_suffix => 'all_products)
expire_fragment(:controller => 'products', :action => 'recent', :action_suffix => 'all_products)
-----------------------------------------------------
If you don't want the cache block to bind to the action that called it, You can
also use globally keyed fragments by calling the cache method with a key, like
so:
[source, ruby]
-----------------------------------------------------
<% cache(:key => ['all_available_products', @latest_product.created_at].join(':')) do %>
All available products:
-----------------------------------------------------
This fragment is then available to all actions in the ProductsController using
the key and can be expired the same way:
[source, ruby]
-----------------------------------------------------
expire_fragment(:key => ['all_available_products', @latest_product.created_at].join(':'))
-----------------------------------------------------
[More: more examples? description of fragment keys and expiration, etc? pagination?]
@ -185,7 +203,7 @@ expire_fragment(:controller => 'producst', :action => 'recent', :action_suffix =
Cache sweeping is a mechanism which allows you to get around having a ton of
expire_{page,action,fragment} calls in your code by moving all the work
required to expire cached content into a ActionController::Caching::Sweeper
required to expire cached content into a `ActionController::Caching::Sweeper`
class that is an Observer and looks for changes to an object via callbacks,
and when a change occurs it expires the caches associated with that object n
an around or after filter.
@ -340,8 +358,7 @@ ActionController::Base.cache_store = :drb_store, "druby://localhost:9192"
-----------------------------------------------------
4) MemCached store: Works like DRbStore, but uses Danga's MemCache instead.
Requires the ruby-memcache library:
gem install ruby-memcache.
Rails uses the bundled memcached-client gem by default.
[source, ruby]
-----------------------------------------------------
@ -355,6 +372,68 @@ ActionController::Base.cache_store = :mem_cache_store, "localhost"
ActionController::Base.cache_store = MyOwnStore.new("parameter")
-----------------------------------------------------
+Note: config.cache_store can be used in place of
ActionController::Base.cache_store in your Rails::Initializer.run block in
environment.rb+
== Conditional GET support
Conditional GETs are a facility of the HTTP spec that provide a way for web
servers to tell browsers that the response to a GET request hasnt changed
since the last request and can be safely pulled from the browser cache.
They work by using the HTTP_IF_NONE_MATCH and HTTP_IF_MODIFIED_SINCE headers to
pass back and forth both a unique content identifier and the timestamp of when
the content was last changed. If the browser makes a request where the content
identifier (etag) or last modified since timestamp matches the servers version
then the server only needs to send back an empty response with a not modified
status.
It is the servers (i.e. our) responsibility to look for a last modified
timestamp and the if-none-match header and determine whether or not to send
back the full response. With conditional-get support in rails this is a pretty
easy task:
[source, ruby]
-----------------------------------------------------
class ProductsController < ApplicationController
def show
@product = Product.find(params[:id])
# If the request is stale according to the given timestamp and etag value
# (i.e. it needs to be processed again) then execute this block
if stale?(:last_modified => @product.updated_at.utc, :etag => @product)
respond_to do |wants|
# ... normal response processing
end
end
# If the request is fresh (i.e. it's not modified) then you don't need to do
# anything. The default render checks for this using the parameters
# used in the previous call to stale? and will automatically send a
# :not_modified. So that's it, you're done.
end
-----------------------------------------------------
If you dont have any special response processing and are using the default
rendering mechanism (i.e. youre not using respond_to or calling render
yourself) then youve got an easy helper in fresh_when:
[source, ruby]
-----------------------------------------------------
class ProductsController < ApplicationController
# This will automatically send back a :not_modified if the request is fresh,
# and will render the default template (product.*) if it's stale.
def show
@product = Product.find(params[:id])
fresh_when :last_modified => @product.published_at.utc, :etag => @article
end
end
-----------------------------------------------------
== Advanced Caching
Along with the built-in mechanisms outlined above, a number of excellent

View file

@ -99,7 +99,7 @@ Using generators will save you a large amount of time by writing *boilerplate co
Let's make our own controller with the controller generator. But what command should we use? Let's ask the generator:
NOTE: All Rails console utilities have help text. For commands that require a lot of input to run correctly, you can just try the command without any parameters (like `rails` or `./script/generate`). For others, you can try adding `--help` or `-h` to the end, as in `./script/server --help`.
NOTE: All Rails console utilities have help text. For commands that require a lot of input to run correctly, you can try the command without any parameters (like `rails` or `./script/generate`). For others, you can try adding `--help` or `-h` to the end, as in `./script/server --help`.
[source,shell]
------------------------------------------------------
@ -143,5 +143,111 @@ $ ./script/generate controller Greeting hello
create app/views/greetings/hello.html.erb
------------------------------------------------------
Look there! Now what all did this generate? It looks like it made sure a bunch of directories were in our application, and created a controller file, a functional test file, a helper for the view, and a view file. All from one command!
Look there! Now what all did this generate? It looks like it made sure a bunch of directories were in our application, and created a controller file, a functional test file, a helper for the view, and a view file.
Let's check out the controller and modify it a little (in `app/controllers/greeting_controller.rb`):
[source,ruby]
------------------------------------------------------
class GreetingController < ApplicationController
def hello
@message = "Hello, how are you today? I am exuberant!"
end
end
------------------------------------------------------
Then the view, to display our nice message (in `app/views/greeting/hello.html.erb`):
[source,html]
------------------------------------------------------
<h1>A Greeting for You!</h1>
<p><%= @message %></p>
------------------------------------------------------
Deal. Go check it out in your browser. Fire up your server. Remember? `./script/server` at the root of your Rails application should do it.
[source,shell]
------------------------------------------------------
$ ./script/server
=> Booting WEBrick...
------------------------------------------------------
The URL will be `http://localhost:3000/greetings/hello`. I'll wait for you to be suitably impressed.
NOTE: With a normal, plain-old Rails application, your URLs will generally follow the pattern of http://(host)/(controller)/(action), and a URL like http://(host)/(controller) will hit the *index* action of that controller.
"What about data, though?", you ask over a cup of coffee. Rails comes with a generator for data models too. Can you guess its generator name?
[source,shell]
------------------------------------------------------
$ ./script/generate model
Usage: ./script/generate model ModelName [field:type, field:type]
...
Examples:
`./script/generate model account`
creates an Account model, test, fixture, and migration:
Model: app/models/account.rb
Test: test/unit/account_test.rb
Fixtures: test/fixtures/accounts.yml
Migration: db/migrate/XXX_add_accounts.rb
`./script/generate model post title:string body:text published:boolean`
creates a Post model with a string title, text body, and published flag.
------------------------------------------------------
Let's set up a simple model called "HighScore" that will keep track of our highest score on video games we play. Then we'll wire up our controller and view to modify and list our scores.
[source,shell]
------------------------------------------------------
$ ./script/generate model HighScore id:integer game:string score:integer
exists app/models/
exists test/unit/
exists test/fixtures/
create app/models/high_score.rb
create test/unit/high_score_test.rb
create test/fixtures/high_scores.yml
create db/migrate
create db/migrate/20081126032945_create_high_scores.rb
------------------------------------------------------
Taking it from the top, we have the *models* directory, where all of your data models live. *test/unit*, where all the unit tests live (gasp! -- unit tests!), fixtures for those tests, a test, the *migrate* directory, where the database-modifying migrations live, and a migration to create the `high_scores` table with the right fields.
The migration requires that we *migrate*, that is, run some Ruby code (living in that `20081126032945_create_high_scores.rb`) to modify the schema of our database. Which database? The sqlite3 database that Rails will create for you when we run the `rake db:migrate` command. We'll talk more about Rake in-depth in a little while.
[source,shell]
------------------------------------------------------
$ rake db:migrate
(in /home/commandsapp)
== CreateHighScores: migrating ===============================================
-- create_table(:high_scores)
-> 0.0070s
== CreateHighScores: migrated (0.0077s) ======================================
------------------------------------------------------
NOTE: Let's talk about unit tests. Unit tests are code that tests and makes assertions about code. In unit testing, we take a little part of code, say a method of a model, and test its inputs and outputs. Unit tests are your friend. The sooner you make peace with the fact that your quality of life will drastically increase when you unit test your code, the better. Seriously. We'll make one in a moment.
Yo! Let's shove a small table into our greeting controller and view, listing our sweet scores.
[source,ruby]
------------------------------------------------------
class GreetingController < ApplicationController
def hello
if request.post?
score = HighScore.new(params[:high_score])
if score.save
flash[:notice] = "New score posted!"
end
end
@scores = HighScore.find(:all)
end
end
------------------------------------------------------
XXX: Go with scaffolding instead, modifying greeting controller for high scores seems dumb.

View file

@ -16,210 +16,179 @@ after-initializer
== Using a Preinitializer
== Initialization Process Settings
== Configuring Rails Components
=== Configuring Active Record
+ActiveRecord::Base+ includej a variety of configuration options:
+logger+ accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then passed on to any new database connections made. You can retrieve this logger by calling +logger+ on either an ActiveRecord model class or an ActiveRecord model instance. Set to nil to disable logging.
+primary_key_prefix_type+ lets you adjust the naming for primary key columns. By default, Rails assumes that primary key columns are named +id+ (and this configuration option doesn't need to be set.) There are two other choices:
* +:table_name+ would make the primary key for the Customer class +customerid+
* +:table_name_with_underscore+ would make the primary key for the Customer class +customer_id+
+table_name_prefix+ lets you set a global string to be prepended to table names. If you set this to +northwest_+, then the Customer class will look for +northwest_customers+ as its table. The default is an empty string.
+table_name_suffix+ lets you set a global string to be appended to table names. If you set this to +_northwest+, then the Customer class will look for +customers_northwest+ as its table. The default is an empty string.
+pluralize_table_names+ specifies whether Rails will look for singular or plural table names in the database. If set to +true+ (the default), then the Customer class will use the +customers+ table. If set to +false+, then the Customers class will use the +customer+ table.
+colorize_logging+ (true by default) specifies whether or not to use ANSI color codes when logging information from ActiveRecord.
+default_timezone+ determines whether to use +Time.local+ (if set to +:local+) or +Time.utc+ (if set to +:utc+) when pulling dates and times from the database. The default is +:local+.
+schema_format+ controls the format for dumping the database schema to a file. The options are +:ruby+ (the default) for a database-independent version that depends on migrations, or +:sql+ for a set of (potentially database-dependent) SQL statements.
+timestamped_migrations+ controls whether migrations are numbered with serial integers or with timestamps. The default is +true+, to use timestamps, which are preferred if there are multiple developers working on the same application.
+lock_optimistically+ controls whether ActiveRecord will use optimistic locking. By default this is +true+.
The MySQL adapter adds one additional configuration option:
+ActiveRecord::ConnectionAdapters::MysqlAdapter.emulate_booleans+ controls whether ActiveRecord will consider all +tinyint(1)+ columns in a MySQL database to be booleans. By default this is +true+.
The schema dumper adds one additional configuration option:
+ActiveRecord::SchemaDumper.ignore_tables+ accepts an array of tables that should _not_ be included in any generated schema file. This setting is ignored unless +ActiveRecord::Base.schema_format == :ruby+.
=== Configuring Action Controller
ActionController::Base includes a number of configuration settings:
+asset_host+ provides a string that is prepended to all of the URL-generating helpers in +AssetHelper+. This is designed to allow moving all javascript, CSS, and image files to a separate asset host.
+consider_all_requests_local+ is generally set to +true+ during development and +false+ during production; if it is set to +true+, then any error will cause detailed debugging information to be dumped in the HTTP response. For finer-grained control, set this to +false+ and implement +local_request?+ to specify which requests should provide debugging information on errors.
+allow_concurrency+ should be set to +true+ to allow concurrent (threadsafe) action processing. Set to +false+ by default.
+param_parsers+ provides an array of handlers that can extract information from incoming HTTP requests and add it to the +params+ hash. By default, parsers for multipart forms, URL-encoded forms, XML, and JSON are active.
+default_charset+ specifies the default character set for all renders. The default is "utf-8".
+logger+ accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then used to log information from Action Controller. Set to nil to disable logging.
+resource_action_separator+ gives the token to be used between resources and actions when building or interpreting RESTful URLs. By default, this is "/".
+resource_path_names+ is a hash of default names for several RESTful actions. By default, the new action is named +new+ and the edit action is named +edit+.
+request_forgery_protection_token+ sets the token parameter name for RequestForgery. Calling +protect_from_forgery+ sets it to +:authenticity_token+ by default.
+optimise_named_routes+ turns on some optimizations in generating the routing table. It is set to +true+ by default.
+use_accept_header+ sets the rules for determining the response format. If this is set to +true+ (the default) then +respond_to+ and +Request#format+ will take the Accept header into account. If it is set to false then the request format will be determined solely by examining +params[:format]+. If there is no +format+ parameter, then the response format will be either HTML or Javascript depending on whether the request is an AJAX request.
+allow_forgery_protection+ enables or disables CSRF protection. By default this is +false+ in test mode and +true+ in all other modes.
+relative_url_root+ can be used to tell Rails that you are deploying to a subdirectory. The default is +ENV['RAILS_RELATIVE_URL_ROOT']+.
The caching code adds two additional settings:
+ActionController::Caching::Pages.page_cache_directory+ sets the directory where Rails will create cached pages for your web server. The default is +Rails.public_path+ (which is usually set to +RAILS_ROOT + "/public"+).
+ActionController::Caching::Pages.page_cache_extension+ sets the extension to be used when generating pages for the cache (this is ignored if the incoming request already has an extension). The default is +.html+.
The dispatcher includes one setting:
+ActionController::Dispatcher.error_file_path+ gives the path where Rails will look for error files such as +404.html+. The default is +Rails.public_path+.
The Active Record session store can also be configured:
+CGI::Session::ActiveRecordStore::Session.data_column_name+ sets the name of the column to use to store session data. By default it is 'data'
=== Configuring Action View
There are only a few configuration options for Action View, starting with four on +ActionView::Base+:
+debug_rjs+ specifies whether RJS responses should be wrapped in a try/catch block that alert()s the caught exception (and then re-raises it). The default is +false+.
+warn_cache_misses+ tells Rails to display a warning whenever an action results in a cache miss on your view paths. The default is +false+.
+field_error_proc+ provides an HTML generator for displaying errors that come from Active Record. The default is +Proc.new{ |html_tag, instance| "<div class=\"fieldWithErrors\">#{html_tag}</div>" }+
+default_form_builder+ tells Rails which form builder to use by default. The default is +ActionView::Helpers::FormBuilder+.
The ERB template handler supplies one additional option:
+ActionView::TemplateHandlers::ERB.erb_trim_mode+ gives the trim mode to be used by ERB. It defaults to +'-'+. See the link:http://www.ruby-doc.org/stdlib/libdoc/erb/rdoc/[ERB documentation] for more information.
=== Configuring Action Mailer
There are a number of settings available on +ActionMailer::Base+:
+template_root+ gives the root folder for Action Mailer templates.
+logger+ accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then used to log information from Action Mailer. Set to nil to disable logging.
+smtp_settings+ allows detailed configuration for the +:smtp+ delivery method. It accepts a hash of options, which can include any of these options:
* <tt>:address</tt> - Allows you to use a remote mail server. Just change it from its default "localhost" setting.
* <tt>:port</tt> - On the off chance that your mail server doesn't run on port 25, you can change it.
* <tt>:domain</tt> - If you need to specify a HELO domain, you can do it here.
* <tt>:user_name</tt> - If your mail server requires authentication, set the username in this setting.
* <tt>:password</tt> - If your mail server requires authentication, set the password in this setting.
* <tt>:authentication</tt> - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of <tt>:plain</tt>, <tt>:login</tt>, <tt>:cram_md5</tt>.
+sendmail_settings+ allows detailed configuration for the +sendmail+ delivery method. It accepts a hash of options, which can include any of these options:
* <tt>:location</tt> - The location of the sendmail executable. Defaults to <tt>/usr/sbin/sendmail</tt>.
* <tt>:arguments</tt> - The command line arguments. Defaults to <tt>-i -t</tt>.
+raise_delivery_errors+ specifies whether to raise an error if email delivery cannot be completed. It defaults to +true+.
+delivery_method+ defines the delivery method. The allowed values are <tt>:smtp</tt> (default), <tt>:sendmail</tt>, and <tt>:test</tt>.
+perform_deliveries+ specifies whether mail will actually be delivered. By default this is +true+; it can be convenient to set it to +false+ for testing.
+default_charset+ tells Action Mailer which character set to use for the body and for encoding the subject. It defaults to +utf-8+.
+default_content_type+ specifies the default content type used for the main part of the message. It defaults to "text/plain"
+default_mime_version+ is the default MIME version for the message. It defaults to +1.0+.
+default_implicit_parts_order+ - When a message is built implicitly (i.e. multiple parts are assembled from templates
which specify the content type in their filenames) this variable controls how the parts are ordered. Defaults to
<tt>["text/html", "text/enriched", "text/plain"]</tt>. Items that appear first in the array have higher priority in the mail client
and appear last in the mime encoded message.
=== Configuring Active Resource
There is a single configuration setting available on +ActiveResource::Base+:
+logger+ accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then used to log information from Active Resource. Set to nil to disable logging.
=== Configuring Active Support
There are a few configuration options available in Active Support:
+ActiveSupport::BufferedLogger.silencer+ is set to +false+ to disable the ability to silence logging in a block. The default is +true+.
+ActiveSupport::Cache::Store.logger+ specifies the logger to use within cache store operations.
+ActiveSupport::Logger.silencer+ is set to +false+ to disable the ability to silence logging in a block. The default is +true+.
=== Configuring Active Model
Active Model currently has a single configuration setting:
+ActiveModel::Errors.default_error_messages is an array containing all of the validation error messages.
== Using Initializers
organization, controlling load order
== Using an After-Initializer
== Rails Environment Settings
ENV
== Changelog ==
http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/28[Lighthouse ticket]
* November 5, 2008: Rough outline by link:../authors.html#mgunderloy[Mike Gunderloy]
actionmailer/lib/action_mailer/base.rb
257: cattr_accessor :logger
267: cattr_accessor :smtp_settings
273: cattr_accessor :sendmail_settings
276: cattr_accessor :raise_delivery_errors
282: cattr_accessor :perform_deliveries
285: cattr_accessor :deliveries
288: cattr_accessor :default_charset
291: cattr_accessor :default_content_type
294: cattr_accessor :default_mime_version
297: cattr_accessor :default_implicit_parts_order
299: cattr_reader :protected_instance_variables
actionmailer/Rakefile
36: rdoc.options << '--line-numbers' << '--inline-source' << '-A cattr_accessor=object'
actionpack/lib/action_controller/base.rb
263: cattr_reader :protected_instance_variables
273: cattr_accessor :asset_host
279: cattr_accessor :consider_all_requests_local
285: cattr_accessor :allow_concurrency
317: cattr_accessor :param_parsers
321: cattr_accessor :default_charset
325: cattr_accessor :logger
329: cattr_accessor :resource_action_separator
333: cattr_accessor :resources_path_names
337: cattr_accessor :request_forgery_protection_token
341: cattr_accessor :optimise_named_routes
351: cattr_accessor :use_accept_header
361: cattr_accessor :relative_url_root
actionpack/lib/action_controller/caching/pages.rb
55: cattr_accessor :page_cache_directory
58: cattr_accessor :page_cache_extension
actionpack/lib/action_controller/caching.rb
37: cattr_reader :cache_store
48: cattr_accessor :perform_caching
actionpack/lib/action_controller/dispatcher.rb
98: cattr_accessor :error_file_path
actionpack/lib/action_controller/mime_type.rb
24: cattr_reader :html_types, :unverifiable_types
actionpack/lib/action_controller/rescue.rb
36: base.cattr_accessor :rescue_responses
40: base.cattr_accessor :rescue_templates
actionpack/lib/action_controller/session/active_record_store.rb
60: cattr_accessor :data_column_name
170: cattr_accessor :connection
173: cattr_accessor :table_name
177: cattr_accessor :session_id_column
181: cattr_accessor :data_column
282: cattr_accessor :session_class
actionpack/lib/action_controller/vendor/html-scanner/html/sanitizer.rb
44: cattr_accessor :included_tags, :instance_writer => false
actionpack/lib/action_view/base.rb
189: cattr_accessor :debug_rjs
193: cattr_accessor :warn_cache_misses
actionpack/lib/action_view/helpers/active_record_helper.rb
7: cattr_accessor :field_error_proc
actionpack/lib/action_view/helpers/form_helper.rb
805: cattr_accessor :default_form_builder
actionpack/lib/action_view/template_handlers/erb.rb
47: cattr_accessor :erb_trim_mode
actionpack/test/active_record_unit.rb
5: cattr_accessor :able_to_connect
6: cattr_accessor :connected
actionpack/test/controller/filters_test.rb
286: cattr_accessor :execution_log
actionpack/test/template/form_options_helper_test.rb
3:TZInfo::Timezone.cattr_reader :loaded_zones
activemodel/lib/active_model/errors.rb
28: cattr_accessor :default_error_messages
activemodel/Rakefile
19: rdoc.options << '--line-numbers' << '--inline-source' << '-A cattr_accessor=object'
activerecord/lib/active_record/attribute_methods.rb
9: base.cattr_accessor :attribute_types_cached_by_default, :instance_writer => false
11: base.cattr_accessor :time_zone_aware_attributes, :instance_writer => false
activerecord/lib/active_record/base.rb
394: cattr_accessor :logger, :instance_writer => false
443: cattr_accessor :configurations, :instance_writer => false
450: cattr_accessor :primary_key_prefix_type, :instance_writer => false
456: cattr_accessor :table_name_prefix, :instance_writer => false
461: cattr_accessor :table_name_suffix, :instance_writer => false
467: cattr_accessor :pluralize_table_names, :instance_writer => false
473: cattr_accessor :colorize_logging, :instance_writer => false
478: cattr_accessor :default_timezone, :instance_writer => false
487: cattr_accessor :schema_format , :instance_writer => false
491: cattr_accessor :timestamped_migrations , :instance_writer => false
activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
11: cattr_accessor :connection_handler, :instance_writer => false
activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
166: cattr_accessor :emulate_booleans
activerecord/lib/active_record/fixtures.rb
498: cattr_accessor :all_loaded_fixtures
activerecord/lib/active_record/locking/optimistic.rb
38: base.cattr_accessor :lock_optimistically, :instance_writer => false
activerecord/lib/active_record/migration.rb
259: cattr_accessor :verbose
activerecord/lib/active_record/schema_dumper.rb
13: cattr_accessor :ignore_tables
activerecord/lib/active_record/serializers/json_serializer.rb
4: base.cattr_accessor :include_root_in_json, :instance_writer => false
activerecord/Rakefile
142: rdoc.options << '--line-numbers' << '--inline-source' << '-A cattr_accessor=object'
activerecord/test/cases/lifecycle_test.rb
61: cattr_reader :last_inherited
activerecord/test/cases/mixin_test.rb
9: cattr_accessor :forced_now_time
activeresource/lib/active_resource/base.rb
206: cattr_accessor :logger
activeresource/Rakefile
43: rdoc.options << '--line-numbers' << '--inline-source' << '-A cattr_accessor=object'
activesupport/lib/active_support/buffered_logger.rb
17: cattr_accessor :silencer
activesupport/lib/active_support/cache.rb
81: cattr_accessor :logger
activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
5:# cattr_accessor :hair_colors
10: def cattr_reader(*syms)
29: def cattr_writer(*syms)
50: def cattr_accessor(*syms)
51: cattr_reader(*syms)
52: cattr_writer(*syms)
activesupport/lib/active_support/core_ext/logger.rb
34: cattr_accessor :silencer
activesupport/test/core_ext/class/attribute_accessor_test.rb
6: cattr_accessor :foo
7: cattr_accessor :bar, :instance_writer => false
activesupport/test/core_ext/module/synchronization_test.rb
6: @target.cattr_accessor :mutex, :instance_writer => false
railties/doc/guides/html/creating_plugins.html
786: cattr_accessor <span style="color: #990000">:</span>yaffle_text_field<span style="color: #990000">,</span> <span style="color: #990000">:</span>yaffle_date_field
860: cattr_accessor <span style="color: #990000">:</span>yaffle_text_field<span style="color: #990000">,</span> <span style="color: #990000">:</span>yaffle_date_field
railties/lib/rails_generator/base.rb
93: cattr_accessor :logger
railties/Rakefile
265: rdoc.options << '--line-numbers' << '--inline-source' << '--accessor' << 'cattr_accessor=object'
railties/test/rails_info_controller_test.rb
12: cattr_accessor :local_request
Rakefile
32: rdoc.options << '-A cattr_accessor=object'
need to look for def self. ???

View file

@ -1,4 +1,4 @@
== Add an `acts_as_yaffle` method to Active Record ==
== Add an 'acts_as' method to Active Record ==
A common pattern in plugins is to add a method called 'acts_as_something' to models. In this case, you want to write a method called 'acts_as_yaffle' that adds a 'squawk' method to your models.

View file

@ -1,46 +1,104 @@
== Appendix ==
If you prefer to use RSpec instead of Test::Unit, you may be interested in the http://github.com/pat-maddox/rspec-plugin-generator/tree/master[RSpec Plugin Generator].
=== References ===
* http://nubyonrails.com/articles/the-complete-guide-to-rails-plugins-part-i
* http://nubyonrails.com/articles/2006/05/09/the-complete-guide-to-rails-plugins-part-ii
* http://github.com/technoweenie/attachment_fu/tree/master
* http://daddy.platte.name/2007/05/rails-plugins-keep-initrb-thin.html
* http://www.mbleigh.com/2008/6/11/gemplugins-a-brief-introduction-to-the-future-of-rails-plugins
* http://weblog.jamisbuck.org/2006/10/26/monkey-patching-rails-extending-routes-2.
=== Contents of 'lib/yaffle.rb' ===
*vendor/plugins/yaffle/lib/yaffle.rb:*
[source, ruby]
----------------------------------------------
require "yaffle/core_ext"
require "yaffle/acts_as_yaffle"
require "yaffle/commands"
require "yaffle/routing"
%w{ models controllers helpers }.each do |dir|
path = File.join(File.dirname(__FILE__), 'app', dir)
$LOAD_PATH << path
ActiveSupport::Dependencies.load_paths << path
ActiveSupport::Dependencies.load_once_paths.delete(path)
end
# optionally:
# Dir.glob(File.join(File.dirname(__FILE__), "db", "migrate", "*")).each do |file|
# require file
# end
----------------------------------------------
=== Final plugin directory structure ===
The final plugin should have a directory structure that looks something like this:
------------------------------------------------
|-- MIT-LICENSE
|-- README
|-- Rakefile
|-- generators
| `-- yaffle
| |-- USAGE
| |-- templates
| | `-- definition.txt
| `-- yaffle_generator.rb
|-- init.rb
|-- install.rb
|-- lib
| |-- acts_as_yaffle.rb
| |-- commands.rb
| |-- core_ext.rb
| |-- routing.rb
| `-- view_helpers.rb
|-- tasks
| `-- yaffle_tasks.rake
|-- test
| |-- acts_as_yaffle_test.rb
| |-- core_ext_test.rb
| |-- database.yml
| |-- debug.log
| |-- routing_test.rb
| |-- schema.rb
| |-- test_helper.rb
| `-- view_helpers_test.rb
|-- uninstall.rb
`-- yaffle_plugin.sqlite3.db
|-- MIT-LICENSE
|-- README
|-- Rakefile
|-- generators
| |-- yaffle_definition
| | |-- USAGE
| | |-- templates
| | | `-- definition.txt
| | `-- yaffle_definition_generator.rb
| |-- yaffle_migration
| | |-- USAGE
| | |-- templates
| | `-- yaffle_migration_generator.rb
| `-- yaffle_route
| |-- USAGE
| |-- templates
| `-- yaffle_route_generator.rb
|-- install.rb
|-- lib
| |-- app
| | |-- controllers
| | | `-- woodpeckers_controller.rb
| | |-- helpers
| | | `-- woodpeckers_helper.rb
| | `-- models
| | `-- woodpecker.rb
| |-- db
| | `-- migrate
| | `-- 20081116181115_create_birdhouses.rb
| |-- yaffle
| | |-- acts_as_yaffle.rb
| | |-- commands.rb
| | |-- core_ext.rb
| | `-- routing.rb
| `-- yaffle.rb
|-- pkg
| `-- yaffle-0.0.1.gem
|-- rails
| `-- init.rb
|-- tasks
| `-- yaffle_tasks.rake
|-- test
| |-- acts_as_yaffle_test.rb
| |-- core_ext_test.rb
| |-- database.yml
| |-- debug.log
| |-- definition_generator_test.rb
| |-- migration_generator_test.rb
| |-- route_generator_test.rb
| |-- routes_test.rb
| |-- schema.rb
| |-- test_helper.rb
| |-- woodpecker_test.rb
| |-- woodpeckers_controller_test.rb
| |-- wookpeckers_helper_test.rb
| |-- yaffle_plugin.sqlite3.db
| `-- yaffle_test.rb
`-- uninstall.rb
------------------------------------------------

View file

@ -1,10 +1,10 @@
== Add a controller ==
== Controllers ==
This section describes how to add a controller named 'woodpeckers' to your plugin that will behave the same as a controller in your main app. This is very similar to adding a model.
You can test your plugin's controller as you would test any other controller:
*vendor/plugins/yaffle/yaffle/woodpeckers_controller_test.rb:*
*vendor/plugins/yaffle/test/woodpeckers_controller_test.rb:*
[source, ruby]
----------------------------------------------
@ -19,6 +19,10 @@ class WoodpeckersControllerTest < Test::Unit::TestCase
@controller = WoodpeckersController.new
@request = ActionController::TestRequest.new
@response = ActionController::TestResponse.new
ActionController::Routing::Routes.draw do |map|
map.resources :woodpeckers
end
end
def test_index

View file

@ -1,11 +1,6 @@
== Extending core classes ==
This section will explain how to add a method to String that will be available anywhere in your rails app by:
* Writing tests for the desired behavior
* Creating and requiring the correct files
=== Creating the test ===
This section will explain how to add a method to String that will be available anywhere in your rails app.
In this example you will add a method to String named `to_squawk`. To begin, create a new test file with a few assertions:
@ -40,26 +35,6 @@ NoMethodError: undefined method `to_squawk' for "Hello World":String
Great - now you are ready to start development.
=== Organize your files ===
A common pattern in rails plugins is to set up the file structure like this:
--------------------------------------------------------
|-- lib
| |-- yaffle
| | `-- core_ext.rb
| `-- yaffle.rb
--------------------------------------------------------
The first thing we need to to is to require our 'lib/yaffle.rb' file from 'rails/init.rb':
*vendor/plugins/yaffle/rails/init.rb*
[source, ruby]
--------------------------------------------------------
require 'yaffle'
--------------------------------------------------------
Then in 'lib/yaffle.rb' require 'lib/core_ext.rb':
*vendor/plugins/yaffle/lib/yaffle.rb*
@ -92,13 +67,13 @@ $ ./script/console
=== Working with init.rb ===
When rails loads plugins it looks for the file named init.rb. However, when the plugin is initialized, 'init.rb' is invoked via `eval` (not `require`) so it has slightly different behavior.
When rails loads plugins it looks for the file named 'init.rb' or 'rails/init.rb'. However, when the plugin is initialized, 'init.rb' is invoked via `eval` (not `require`) so it has slightly different behavior.
Under certain circumstances if you reopen classes or modules in 'init.rb' you may inadvertently create a new class, rather than reopening an existing class. A better alternative is to reopen the class in a different file, and require that file from `init.rb`, as shown above.
If you must reopen a class in `init.rb` you can use `module_eval` or `class_eval` to avoid any issues:
*vendor/plugins/yaffle/init.rb*
*vendor/plugins/yaffle/rails/init.rb*
[source, ruby]
---------------------------------------------------
@ -111,7 +86,7 @@ end
Another way is to explicitly define the top-level module space for all modules and classes, like `::Hash`:
*vendor/plugins/yaffle/init.rb*
*vendor/plugins/yaffle/rails/init.rb*
[source, ruby]
---------------------------------------------------

View file

@ -0,0 +1,50 @@
== PluginGems ==
Turning your rails plugin into a gem is a simple and straightforward task. This section will cover how to turn your plugin into a gem. It will not cover how to distribute that gem.
Historically rails plugins loaded the plugin's 'init.rb' file. In fact some plugins contain all of their code in that one file. To be compatible with plugins, 'init.rb' was moved to 'rails/init.rb'.
It's common practice to put any developer-centric rake tasks (such as tests, rdoc and gem package tasks) in 'Rakefile'. A rake task that packages the gem might look like this:
*vendor/plugins/yaffle/Rakefile:*
[source, ruby]
----------------------------------------------
PKG_FILES = FileList[
'[a-zA-Z]*',
'generators/**/*',
'lib/**/*',
'rails/**/*',
'tasks/**/*',
'test/**/*'
]
spec = Gem::Specification.new do |s|
s.name = "yaffle"
s.version = "0.0.1"
s.author = "Gleeful Yaffler"
s.email = "yaffle@example.com"
s.homepage = "http://yafflers.example.com/"
s.platform = Gem::Platform::RUBY
s.summary = "Sharing Yaffle Goodness"
s.files = PKG_FILES.to_a
s.require_path = "lib"
s.has_rdoc = false
s.extra_rdoc_files = ["README"]
end
desc 'Turn this plugin into a gem.'
Rake::GemPackageTask.new(spec) do |pkg|
pkg.gem_spec = spec
end
----------------------------------------------
To build and install the gem locally, run the following commands:
----------------------------------------------
cd vendor/plugins/yaffle
rake gem
sudo gem install pkg/yaffle-0.0.1.gem
----------------------------------------------
To test this, create a new rails app, add 'config.gem "yaffle"' to environment.rb and all of your plugin's functionality will be available to you.

View file

@ -0,0 +1,144 @@
== Generator Commands ==
You may have noticed above that you can used one of the built-in rails migration commands `migration_template`. If your plugin needs to add and remove lines of text from existing files you will need to write your own generator methods.
This section describes how you you can create your own commands to add and remove a line of text from 'config/routes.rb'.
To start, add the following test method:
*vendor/plugins/yaffle/test/route_generator_test.rb*
[source, ruby]
-----------------------------------------------------------
require File.dirname(__FILE__) + '/test_helper.rb'
require 'rails_generator'
require 'rails_generator/scripts/generate'
require 'rails_generator/scripts/destroy'
class RouteGeneratorTest < Test::Unit::TestCase
def setup
FileUtils.mkdir_p(File.join(fake_rails_root, "config"))
end
def teardown
FileUtils.rm_r(fake_rails_root)
end
def test_generates_route
content = <<-END
ActionController::Routing::Routes.draw do |map|
map.connect ':controller/:action/:id'
map.connect ':controller/:action/:id.:format'
end
END
File.open(routes_path, 'wb') {|f| f.write(content) }
Rails::Generator::Scripts::Generate.new.run(["yaffle_route"], :destination => fake_rails_root)
assert_match /map\.yaffles/, File.read(routes_path)
end
def test_destroys_route
content = <<-END
ActionController::Routing::Routes.draw do |map|
map.yaffles
map.connect ':controller/:action/:id'
map.connect ':controller/:action/:id.:format'
end
END
File.open(routes_path, 'wb') {|f| f.write(content) }
Rails::Generator::Scripts::Destroy.new.run(["yaffle_route"], :destination => fake_rails_root)
assert_no_match /map\.yaffles/, File.read(routes_path)
end
private
def fake_rails_root
File.join(File.dirname(__FILE__), "rails_root")
end
def routes_path
File.join(fake_rails_root, "config", "routes.rb")
end
end
-----------------------------------------------------------
Run `rake` to watch the test fail, then make the test pass add the following:
*vendor/plugins/yaffle/lib/yaffle.rb*
[source, ruby]
-----------------------------------------------------------
require "yaffle/commands"
-----------------------------------------------------------
*vendor/plugins/yaffle/lib/yaffle/commands.rb*
[source, ruby]
-----------------------------------------------------------
require 'rails_generator'
require 'rails_generator/commands'
module Yaffle #:nodoc:
module Generator #:nodoc:
module Commands #:nodoc:
module Create
def yaffle_route
logger.route "map.yaffle"
look_for = 'ActionController::Routing::Routes.draw do |map|'
unless options[:pretend]
gsub_file('config/routes.rb', /(#{Regexp.escape(look_for)})/mi){|match| "#{match}\n map.yaffles\n"}
end
end
end
module Destroy
def yaffle_route
logger.route "map.yaffle"
gsub_file 'config/routes.rb', /\n.+?map\.yaffles/mi, ''
end
end
module List
def yaffle_route
end
end
module Update
def yaffle_route
end
end
end
end
end
Rails::Generator::Commands::Create.send :include, Yaffle::Generator::Commands::Create
Rails::Generator::Commands::Destroy.send :include, Yaffle::Generator::Commands::Destroy
Rails::Generator::Commands::List.send :include, Yaffle::Generator::Commands::List
Rails::Generator::Commands::Update.send :include, Yaffle::Generator::Commands::Update
-----------------------------------------------------------
*vendor/plugins/yaffle/generators/yaffle/yaffle_route_generator.rb*
[source, ruby]
-----------------------------------------------------------
class YaffleRouteGenerator < Rails::Generator::Base
def manifest
record do |m|
m.yaffle_route
end
end
end
-----------------------------------------------------------
To see this work, type:
-----------------------------------------------------------
./script/generate yaffle_route
./script/destroy yaffle_route
-----------------------------------------------------------
.Editor's note:
NOTE: If you haven't set up the custom route from above, 'script/destroy' will fail and you'll have to remove it manually.

View file

@ -0,0 +1,98 @@
== Generators ==
Many plugins ship with generators. When you created the plugin above, you specified the --with-generator option, so you already have the generator stubs in 'vendor/plugins/yaffle/generators/yaffle'.
Building generators is a complex topic unto itself and this section will cover one small aspect of generators: generating a simple text file.
=== Testing generators ===
Many rails plugin authors do not test their generators, however testing generators is quite simple. A typical generator test does the following:
* Creates a new fake rails root directory that will serve as destination
* Runs the generator
* Asserts that the correct files were generated
* Removes the fake rails root
This section will describe how to create a simple generator that adds a file. For the generator in this section, the test could look something like this:
*vendor/plugins/yaffle/test/definition_generator_test.rb*
[source, ruby]
------------------------------------------------------------------
require File.dirname(__FILE__) + '/test_helper.rb'
require 'rails_generator'
require 'rails_generator/scripts/generate'
class DefinitionGeneratorTest < Test::Unit::TestCase
def setup
FileUtils.mkdir_p(fake_rails_root)
@original_files = file_list
end
def teardown
FileUtils.rm_r(fake_rails_root)
end
def test_generates_correct_file_name
Rails::Generator::Scripts::Generate.new.run(["yaffle_definition"], :destination => fake_rails_root)
new_file = (file_list - @original_files).first
assert_equal "definition.txt", File.basename(new_file)
end
private
def fake_rails_root
File.join(File.dirname(__FILE__), 'rails_root')
end
def file_list
Dir.glob(File.join(fake_rails_root, "*"))
end
end
------------------------------------------------------------------
You can run 'rake' from the plugin directory to see this fail. Unless you are doing more advanced generator commands it typically suffices to just test the Generate script, and trust that rails will handle the Destroy and Update commands for you.
To make it pass, create the generator:
*vendor/plugins/yaffle/generators/yaffle_definition/yaffle_definition_generator.rb*
[source, ruby]
------------------------------------------------------------------
class YaffleDefinitionGenerator < Rails::Generator::Base
def manifest
record do |m|
m.file "definition.txt", "definition.txt"
end
end
end
------------------------------------------------------------------
=== The USAGE file ===
If you plan to distribute your plugin, developers will expect at least a minimum of documentation. You can add simple documentation to the generator by updating the USAGE file.
Rails ships with several built-in generators. You can see all of the generators available to you by typing the following at the command line:
------------------------------------------------------------------
./script/generate
------------------------------------------------------------------
You should see something like this:
------------------------------------------------------------------
Installed Generators
Plugins (vendor/plugins): yaffle_definition
Builtin: controller, integration_test, mailer, migration, model, observer, plugin, resource, scaffold, session_migration
------------------------------------------------------------------
When you run `script/generate yaffle_definition -h` you should see the contents of your 'vendor/plugins/yaffle/generators/yaffle_definition/USAGE'.
For this plugin, update the USAGE file could look like this:
------------------------------------------------------------------
Description:
Adds a file with the definition of a Yaffle to the app's main directory
------------------------------------------------------------------

View file

@ -1,4 +1,4 @@
== Add a helper ==
== Helpers ==
This section describes how to add a helper named 'WoodpeckersHelper' to your plugin that will behave the same as a helper in your main app. This is very similar to adding a model and a controller.
@ -30,8 +30,6 @@ This is just a simple test to make sure the helper is being loaded correctly. A
ActiveSupport::Dependencies.load_paths << path
ActiveSupport::Dependencies.load_once_paths.delete(path)
end
ActionView::Base.send :include, WoodpeckersHelper
----------------------------------------------

View file

@ -29,24 +29,32 @@ This guide describes how to build a test-driven plugin that will:
For the purpose of this guide pretend for a moment that you are an avid bird watcher. Your favorite bird is the Yaffle, and you want to create a plugin that allows other developers to share in the Yaffle goodness. First, you need to get setup for development.
include::test_setup.txt[]
include::setup.txt[]
include::tests.txt[]
include::core_ext.txt[]
include::acts_as_yaffle.txt[]
include::migration_generator.txt[]
include::generator_method.txt[]
include::models.txt[]
include::controllers.txt[]
include::helpers.txt[]
include::custom_route.txt[]
include::routes.txt[]
include::odds_and_ends.txt[]
include::generators.txt[]
include::generator_commands.txt[]
include::migrations.txt[]
include::tasks.txt[]
include::gems.txt[]
include::rdoc.txt[]
include::appendix.txt[]

View file

@ -1,156 +0,0 @@
== Create a generator ==
Many plugins ship with generators. When you created the plugin above, you specified the --with-generator option, so you already have the generator stubs in 'vendor/plugins/yaffle/generators/yaffle'.
Building generators is a complex topic unto itself and this section will cover one small aspect of generators: creating a generator that adds a time-stamped migration.
To create a generator you must:
* Add your instructions to the 'manifest' method of the generator
* Add any necessary template files to the templates directory
* Test the generator manually by running various combinations of `script/generate` and `script/destroy`
* Update the USAGE file to add helpful documentation for your generator
=== Testing generators ===
Many rails plugin authors do not test their generators, however testing generators is quite simple. A typical generator test does the following:
* Creates a new fake rails root directory that will serve as destination
* Runs the generator forward and backward, making whatever assertions are necessary
* Removes the fake rails root
For the generator in this section, the test could look something like this:
*vendor/plugins/yaffle/test/yaffle_generator_test.rb*
[source, ruby]
------------------------------------------------------------------
require File.dirname(__FILE__) + '/test_helper.rb'
require 'rails_generator'
require 'rails_generator/scripts/generate'
require 'rails_generator/scripts/destroy'
class GeneratorTest < Test::Unit::TestCase
def fake_rails_root
File.join(File.dirname(__FILE__), 'rails_root')
end
def file_list
Dir.glob(File.join(fake_rails_root, "db", "migrate", "*"))
end
def setup
FileUtils.mkdir_p(fake_rails_root)
@original_files = file_list
end
def teardown
FileUtils.rm_r(fake_rails_root)
end
def test_generates_correct_file_name
Rails::Generator::Scripts::Generate.new.run(["yaffle", "bird"], :destination => fake_rails_root)
new_file = (file_list - @original_files).first
assert_match /add_yaffle_fields_to_bird/, new_file
end
end
------------------------------------------------------------------
You can run 'rake' from the plugin directory to see this fail. Unless you are doing more advanced generator commands it typically suffices to just test the Generate script, and trust that rails will handle the Destroy and Update commands for you.
=== Adding to the manifest ===
This example will demonstrate how to use one of the built-in generator methods named 'migration_template' to create a migration file. To start, update your generator file to look like this:
*vendor/plugins/yaffle/generators/yaffle/yaffle_generator.rb*
[source, ruby]
------------------------------------------------------------------
class YaffleGenerator < Rails::Generator::NamedBase
def manifest
record do |m|
m.migration_template 'migration:migration.rb', "db/migrate", {:assigns => yaffle_local_assigns,
:migration_file_name => "add_yaffle_fields_to_#{custom_file_name}"
}
end
end
private
def custom_file_name
custom_name = class_name.underscore.downcase
custom_name = custom_name.pluralize if ActiveRecord::Base.pluralize_table_names
end
def yaffle_local_assigns
returning(assigns = {}) do
assigns[:migration_action] = "add"
assigns[:class_name] = "add_yaffle_fields_to_#{custom_file_name}"
assigns[:table_name] = custom_file_name
assigns[:attributes] = [Rails::Generator::GeneratedAttribute.new("last_squawk", "string")]
end
end
end
------------------------------------------------------------------
The generator creates a new file in 'db/migrate' with a timestamp and an 'add_column' statement. It reuses the built in rails `migration_template` method, and reuses the built-in rails migration template.
It's courteous to check to see if table names are being pluralized whenever you create a generator that needs to be aware of table names. This way people using your generator won't have to manually change the generated files if they've turned pluralization off.
=== Manually test the generator ===
To run the generator, type the following at the command line:
------------------------------------------------------------------
./script/generate yaffle bird
------------------------------------------------------------------
and you will see a new file:
*db/migrate/20080529225649_add_yaffle_fields_to_birds.rb*
[source, ruby]
------------------------------------------------------------------
class AddYaffleFieldsToBirds < ActiveRecord::Migration
def self.up
add_column :birds, :last_squawk, :string
end
def self.down
remove_column :birds, :last_squawk
end
end
------------------------------------------------------------------
=== The USAGE file ===
Rails ships with several built-in generators. You can see all of the generators available to you by typing the following at the command line:
------------------------------------------------------------------
script/generate
------------------------------------------------------------------
You should see something like this:
------------------------------------------------------------------
Installed Generators
Plugins (vendor/plugins): yaffle
Builtin: controller, integration_test, mailer, migration, model, observer, plugin, resource, scaffold, session_migration
------------------------------------------------------------------
When you run `script/generate yaffle` you should see the contents of your 'vendor/plugins/yaffle/generators/yaffle/USAGE' file.
For this plugin, update the USAGE file looks like this:
------------------------------------------------------------------
Description:
Creates a migration that adds yaffle squawk fields to the given model
Example:
./script/generate yaffle hickwall
This will create:
db/migrate/TIMESTAMP_add_yaffle_fields_to_hickwall
------------------------------------------------------------------

View file

@ -0,0 +1,213 @@
== Migrations ==
If your plugin requires changes to the app's database you will likely want to somehow add migrations. Rails does not include any built-in support for calling migrations from plugins, but you can still make it easy for developers to call migrations from plugins.
If you have a very simple needs, like creating a table that will always have the same name and columns, then you can use a more simple solution, like creating a custom rake task or method. If your migration needs user input to supply table names or other options, you probably want to opt for generating a migration.
Let's say you have the following migration in your plugin:
*vendor/plugins/yaffle/lib/db/migrate/20081116181115_create_birdhouses.rb:*
[source, ruby]
----------------------------------------------
class CreateBirdhouses < ActiveRecord::Migration
def self.up
create_table :birdhouses, :force => true do |t|
t.string :name
t.timestamps
end
end
def self.down
drop_table :birdhouses
end
end
----------------------------------------------
Here are a few possibilities for how to allow developers to use your plugin migrations:
=== Create a custom rake task ===
*vendor/plugins/yaffle/lib/db/migrate/20081116181115_create_birdhouses.rb:*
[source, ruby]
----------------------------------------------
class CreateBirdhouses < ActiveRecord::Migration
def self.up
create_table :birdhouses, :force => true do |t|
t.string :name
t.timestamps
end
end
def self.down
drop_table :birdhouses
end
end
----------------------------------------------
*vendor/plugins/yaffle/tasks/yaffle.rake:*
[source, ruby]
----------------------------------------------
namespace :db do
namespace :migrate do
desc "Migrate the database through scripts in vendor/plugins/yaffle/lib/db/migrate and update db/schema.rb by invoking db:schema:dump. Target specific version with VERSION=x. Turn off output with VERBOSE=false."
task :yaffle => :environment do
ActiveRecord::Migration.verbose = ENV["VERBOSE"] ? ENV["VERBOSE"] == "true" : true
ActiveRecord::Migrator.migrate("vendor/plugins/yaffle/lib/db/migrate/", ENV["VERSION"] ? ENV["VERSION"].to_i : nil)
Rake::Task["db:schema:dump"].invoke if ActiveRecord::Base.schema_format == :ruby
end
end
end
----------------------------------------------
=== Call migrations directly ===
*vendor/plugins/yaffle/lib/yaffle.rb:*
[source, ruby]
----------------------------------------------
Dir.glob(File.join(File.dirname(__FILE__), "db", "migrate", "*")).each do |file|
require file
end
----------------------------------------------
*db/migrate/20081116181115_create_birdhouses.rb:*
[source, ruby]
----------------------------------------------
class CreateBirdhouses < ActiveRecord::Migration
def self.up
Yaffle::CreateBirdhouses.up
end
def self.down
Yaffle::CreateBirdhouses.down
end
end
----------------------------------------------
.Editor's note:
NOTE: several plugin frameworks such as Desert and Engines provide more advanced plugin functionality.
=== Generate migrations ===
Generating migrations has several advantages over other methods. Namely, you can allow other developers to more easily customize the migration. The flow looks like this:
* call your script/generate script and pass in whatever options they need
* examine the generated migration, adding/removing columns or other options as necessary
This example will demonstrate how to use one of the built-in generator methods named 'migration_template' to create a migration file. Extending the rails migration generator requires a somewhat intimate knowledge of the migration generator internals, so it's best to write a test first:
*vendor/plugins/yaffle/test/yaffle_migration_generator_test.rb*
[source, ruby]
------------------------------------------------------------------
require File.dirname(__FILE__) + '/test_helper.rb'
require 'rails_generator'
require 'rails_generator/scripts/generate'
class MigrationGeneratorTest < Test::Unit::TestCase
def setup
FileUtils.mkdir_p(fake_rails_root)
@original_files = file_list
end
def teardown
ActiveRecord::Base.pluralize_table_names = true
FileUtils.rm_r(fake_rails_root)
end
def test_generates_correct_file_name
Rails::Generator::Scripts::Generate.new.run(["yaffle_migration", "some_name_nobody_is_likely_to_ever_use_in_a_real_migration"], :destination => fake_rails_root)
new_file = (file_list - @original_files).first
assert_match /add_yaffle_fields_to_some_name_nobody_is_likely_to_ever_use_in_a_real_migrations/, new_file
assert_match /add_column :some_name_nobody_is_likely_to_ever_use_in_a_real_migrations do |t|/, File.read(new_file)
end
def test_pluralizes_properly
ActiveRecord::Base.pluralize_table_names = false
Rails::Generator::Scripts::Generate.new.run(["yaffle_migration", "some_name_nobody_is_likely_to_ever_use_in_a_real_migration"], :destination => fake_rails_root)
new_file = (file_list - @original_files).first
assert_match /add_yaffle_fields_to_some_name_nobody_is_likely_to_ever_use_in_a_real_migration/, new_file
assert_match /add_column :some_name_nobody_is_likely_to_ever_use_in_a_real_migration do |t|/, File.read(new_file)
end
private
def fake_rails_root
File.join(File.dirname(__FILE__), 'rails_root')
end
def file_list
Dir.glob(File.join(fake_rails_root, "db", "migrate", "*"))
end
end
------------------------------------------------------------------
.Editor's note:
NOTE: the migration generator checks to see if a migation already exists, and it's hard-coded to check the 'db/migrate' directory. As a result, if your test tries to generate a migration that already exists in the app, it will fail. The easy workaround is to make sure that the name you generate in your test is very unlikely to actually appear in the app.
After running the test with 'rake' you can make it pass with:
*vendor/plugins/yaffle/generators/yaffle/yaffle_generator.rb*
[source, ruby]
------------------------------------------------------------------
class YaffleMigrationGenerator < Rails::Generator::NamedBase
def manifest
record do |m|
m.migration_template 'migration:migration.rb', "db/migrate", {:assigns => yaffle_local_assigns,
:migration_file_name => "add_yaffle_fields_to_#{custom_file_name}"
}
end
end
private
def custom_file_name
custom_name = class_name.underscore.downcase
custom_name = custom_name.pluralize if ActiveRecord::Base.pluralize_table_names
custom_name
end
def yaffle_local_assigns
returning(assigns = {}) do
assigns[:migration_action] = "add"
assigns[:class_name] = "add_yaffle_fields_to_#{custom_file_name}"
assigns[:table_name] = custom_file_name
assigns[:attributes] = [Rails::Generator::GeneratedAttribute.new("last_squawk", "string")]
end
end
end
------------------------------------------------------------------
The generator creates a new file in 'db/migrate' with a timestamp and an 'add_column' statement. It reuses the built in rails `migration_template` method, and reuses the built-in rails migration template.
It's courteous to check to see if table names are being pluralized whenever you create a generator that needs to be aware of table names. This way people using your generator won't have to manually change the generated files if they've turned pluralization off.
To run the generator, type the following at the command line:
------------------------------------------------------------------
./script/generate yaffle_migration bird
------------------------------------------------------------------
and you will see a new file:
*db/migrate/20080529225649_add_yaffle_fields_to_birds.rb*
[source, ruby]
------------------------------------------------------------------
class AddYaffleFieldsToBirds < ActiveRecord::Migration
def self.up
add_column :birds, :last_squawk, :string
end
def self.down
remove_column :birds, :last_squawk
end
end
------------------------------------------------------------------

View file

@ -1,4 +1,4 @@
== Add a model ==
== Models ==
This section describes how to add a model named 'Woodpecker' to your plugin that will behave the same as a model in your main app. When storing models, controllers, views and helpers in your plugin, it's customary to keep them in directories that match the rails directories. For this example, create a file structure like this:
@ -66,11 +66,9 @@ Finally, add the following to your plugin's 'schema.rb':
[source, ruby]
----------------------------------------------
ActiveRecord::Schema.define(:version => 0) do
create_table :woodpeckers, :force => true do |t|
t.string :name
end
create_table :woodpeckers, :force => true do |t|
t.string :name
end
----------------------------------------------
Now your test should be passing, and you should be able to use the Woodpecker model from within your rails app, and any changes made to it are reflected immediately when running in development mode.
Now your test should be passing, and you should be able to use the Woodpecker model from within your rails app, and any changes made to it are reflected immediately when running in development mode.

View file

@ -1,69 +0,0 @@
== Odds and ends ==
=== Generate RDoc Documentation ===
Once your plugin is stable, the tests pass on all database and you are ready to deploy do everyone else a favor and document it! Luckily, writing documentation for your plugin is easy.
The first step is to update the README file with detailed information about how to use your plugin. A few key things to include are:
* Your name.
* How to install.
* How to add the functionality to the app (several examples of common use cases).
* Warning, gotchas or tips that might help save users time.
Once your README is solid, go through and add rdoc comments to all of the methods that developers will use.
Before you generate your documentation, be sure to go through and add nodoc comments to those modules and methods that are not important to your users.
Once your comments are good to go, navigate to your plugin directory and run:
rake rdoc
=== Write custom Rake tasks in your plugin ===
When you created the plugin with the built-in rails generator, it generated a rake file for you in 'vendor/plugins/yaffle/tasks/yaffle.rake'. Any rake task you add here will be available to the app.
Many plugin authors put all of their rake tasks into a common namespace that is the same as the plugin, like so:
*vendor/plugins/yaffle/tasks/yaffle.rake*
[source, ruby]
---------------------------------------------------------
namespace :yaffle do
desc "Prints out the word 'Yaffle'"
task :squawk => :environment do
puts "squawk!"
end
end
---------------------------------------------------------
When you run `rake -T` from your plugin you will see:
---------------------------------------------------------
yaffle:squawk # Prints out the word 'Yaffle'
---------------------------------------------------------
You can add as many files as you want in the tasks directory, and if they end in .rake Rails will pick them up.
=== Store plugins in alternate locations ===
You can store plugins wherever you want - you just have to add those plugins to the plugins path in 'environment.rb'.
Since the plugin is only loaded after the plugin paths are defined, you can't redefine this in your plugins - but it may be good to now.
You can even store plugins inside of other plugins for complete plugin madness!
[source, ruby]
---------------------------------------------------------
config.plugin_paths << File.join(RAILS_ROOT,"vendor","plugins","yaffle","lib","plugins")
---------------------------------------------------------
=== Create your own Plugin Loaders and Plugin Locators ===
If the built-in plugin behavior is inadequate, you can change almost every aspect of the location and loading process. You can write your own plugin locators and plugin loaders, but that's beyond the scope of this tutorial.
=== Use Custom Plugin Generators ===
If you are an RSpec fan, you can install the `rspec_plugin_generator` gem, which will generate the spec folder and database for you. See http://github.com/pat-maddox/rspec-plugin-generator/tree/master.

View file

@ -0,0 +1,18 @@
== RDoc Documentation ==
Once your plugin is stable and you are ready to deploy do everyone else a favor and document it! Luckily, writing documentation for your plugin is easy.
The first step is to update the README file with detailed information about how to use your plugin. A few key things to include are:
* Your name
* How to install
* How to add the functionality to the app (several examples of common use cases)
* Warning, gotchas or tips that might help save users time
Once your README is solid, go through and add rdoc comments to all of the methods that developers will use. It's also customary to add '#:nodoc:' comments to those parts of the code that are not part of the public api.
Once your comments are good to go, navigate to your plugin directory and run:
---------------------------------------------------------
rake rdoc
---------------------------------------------------------

View file

@ -1,6 +1,8 @@
== Add a Custom Route ==
== Routes ==
Testing routes in plugins can be complex, especially if the controllers are also in the plugin itself. Jamis Buck showed a great example of this in http://weblog.jamisbuck.org/2006/10/26/monkey-patching-rails-extending-routes-2.
In a standard 'routes.rb' file you use routes like 'map.connect' or 'map.resources'. You can add your own custom routes from a plugin. This section will describe how to add a custom method called that can be called with 'map.yaffles'.
Testing routes from plugins is slightly different from testing routes in a standard rails app. To begin, add a test like this:
*vendor/plugins/yaffle/test/routing_test.rb*
@ -22,10 +24,6 @@ class RoutingTest < Test::Unit::TestCase
private
# yes, I know about assert_recognizes, but it has proven problematic to
# use in these tests, since it uses RouteSet#recognize (which actually
# tries to instantiate the controller) and because it uses an awkward
# parameter order.
def assert_recognition(method, path, options)
result = ActionController::Routing::Routes.recognize_path(path, :method => method)
assert_equal options, result
@ -33,15 +31,16 @@ class RoutingTest < Test::Unit::TestCase
end
--------------------------------------------------------
*vendor/plugins/yaffle/init.rb*
Once you see the tests fail by running 'rake', you can make them pass with:
*vendor/plugins/yaffle/lib/yaffle.rb*
[source, ruby]
--------------------------------------------------------
require "routing"
ActionController::Routing::RouteSet::Mapper.send :include, Yaffle::Routing::MapperExtensions
require "yaffle/routing"
--------------------------------------------------------
*vendor/plugins/yaffle/lib/routing.rb*
*vendor/plugins/yaffle/lib/yaffle/routing.rb*
[source, ruby]
--------------------------------------------------------
@ -54,6 +53,8 @@ module Yaffle #:nodoc:
end
end
end
ActionController::Routing::RouteSet::Mapper.send :include, Yaffle::Routing::MapperExtensions
--------------------------------------------------------
*config/routes.rb*
@ -61,7 +62,6 @@ end
[source, ruby]
--------------------------------------------------------
ActionController::Routing::Routes.draw do |map|
...
map.yaffles
end
--------------------------------------------------------

View file

@ -0,0 +1,84 @@
== Setup ==
=== Create the basic app ===
The examples in this guide require that you have a working rails application. To create a simple rails app execute:
------------------------------------------------
gem install rails
rails yaffle_guide
cd yaffle_guide
script/generate scaffold bird name:string
rake db:migrate
script/server
------------------------------------------------
Then navigate to http://localhost:3000/birds. Make sure you have a functioning rails app before continuing.
.Editor's note:
NOTE: The aforementioned instructions will work for sqlite3. For more detailed instructions on how to create a rails app for other databases see the API docs.
=== Generate the plugin skeleton ===
Rails ships with a plugin generator which creates a basic plugin skeleton. Pass the plugin name, either 'CamelCased' or 'under_scored', as an argument. Pass `\--with-generator` to add an example generator also.
This creates a plugin in 'vendor/plugins' including an 'init.rb' and 'README' as well as standard 'lib', 'task', and 'test' directories.
Examples:
----------------------------------------------
./script/generate plugin yaffle
./script/generate plugin yaffle --with-generator
----------------------------------------------
To get more detailed help on the plugin generator, type `./script/generate plugin`.
Later on this guide will describe how to work with generators, so go ahead and generate your plugin with the `\--with-generator` option now:
----------------------------------------------
./script/generate plugin yaffle --with-generator
----------------------------------------------
You should see the following output:
----------------------------------------------
create vendor/plugins/yaffle/lib
create vendor/plugins/yaffle/tasks
create vendor/plugins/yaffle/test
create vendor/plugins/yaffle/README
create vendor/plugins/yaffle/MIT-LICENSE
create vendor/plugins/yaffle/Rakefile
create vendor/plugins/yaffle/init.rb
create vendor/plugins/yaffle/install.rb
create vendor/plugins/yaffle/uninstall.rb
create vendor/plugins/yaffle/lib/yaffle.rb
create vendor/plugins/yaffle/tasks/yaffle_tasks.rake
create vendor/plugins/yaffle/test/core_ext_test.rb
create vendor/plugins/yaffle/generators
create vendor/plugins/yaffle/generators/yaffle
create vendor/plugins/yaffle/generators/yaffle/templates
create vendor/plugins/yaffle/generators/yaffle/yaffle_generator.rb
create vendor/plugins/yaffle/generators/yaffle/USAGE
----------------------------------------------
=== Organize your files ===
To make it easy to organize your files and to make the plugin more compatible with GemPlugins, start out by altering your file system to look like this:
--------------------------------------------------------
|-- lib
| |-- yaffle
| `-- yaffle.rb
`-- rails
|
`-- init.rb
--------------------------------------------------------
*vendor/plugins/yaffle/rails/init.rb*
[source, ruby]
--------------------------------------------------------
require 'yaffle'
--------------------------------------------------------
Now you can add any 'require' statements to 'lib/yaffle.rb' and keep 'init.rb' clean.

View file

@ -0,0 +1,27 @@
== Rake tasks ==
When you created the plugin with the built-in rails generator, it generated a rake file for you in 'vendor/plugins/yaffle/tasks/yaffle.rake'. Any rake task you add here will be available to the app.
Many plugin authors put all of their rake tasks into a common namespace that is the same as the plugin, like so:
*vendor/plugins/yaffle/tasks/yaffle.rake*
[source, ruby]
---------------------------------------------------------
namespace :yaffle do
desc "Prints out the word 'Yaffle'"
task :squawk => :environment do
puts "squawk!"
end
end
---------------------------------------------------------
When you run `rake -T` from your plugin you will see:
---------------------------------------------------------
yaffle:squawk # Prints out the word 'Yaffle'
---------------------------------------------------------
You can add as many files as you want in the tasks directory, and if they end in .rake Rails will pick them up.
Note that tasks from 'vendor/plugins/yaffle/Rakefile' are not available to the main app.

View file

@ -0,0 +1,165 @@
== Tests ==
In this guide you will learn how to test your plugin against multiple different database adapters using Active Record. To setup your plugin to allow for easy testing you'll need to add 3 files:
* A 'database.yml' file with all of your connection strings
* A 'schema.rb' file with your table definitions
* A test helper method that sets up the database
=== Test Setup ===
*vendor/plugins/yaffle/test/database.yml:*
----------------------------------------------
sqlite:
:adapter: sqlite
:dbfile: vendor/plugins/yaffle/test/yaffle_plugin.sqlite.db
sqlite3:
:adapter: sqlite3
:dbfile: vendor/plugins/yaffle/test/yaffle_plugin.sqlite3.db
postgresql:
:adapter: postgresql
:username: postgres
:password: postgres
:database: yaffle_plugin_test
:min_messages: ERROR
mysql:
:adapter: mysql
:host: localhost
:username: root
:password: password
:database: yaffle_plugin_test
----------------------------------------------
For this guide you'll need 2 tables/models, Hickwalls and Wickwalls, so add the following:
*vendor/plugins/yaffle/test/schema.rb:*
[source, ruby]
----------------------------------------------
ActiveRecord::Schema.define(:version => 0) do
create_table :hickwalls, :force => true do |t|
t.string :name
t.string :last_squawk
t.datetime :last_squawked_at
end
create_table :wickwalls, :force => true do |t|
t.string :name
t.string :last_tweet
t.datetime :last_tweeted_at
end
create_table :woodpeckers, :force => true do |t|
t.string :name
end
end
----------------------------------------------
*vendor/plugins/yaffle/test/test_helper.rb:*
[source, ruby]
----------------------------------------------
ENV['RAILS_ENV'] = 'test'
ENV['RAILS_ROOT'] ||= File.dirname(__FILE__) + '/../../../..'
require 'test/unit'
require File.expand_path(File.join(ENV['RAILS_ROOT'], 'config/environment.rb'))
def load_schema
config = YAML::load(IO.read(File.dirname(__FILE__) + '/database.yml'))
ActiveRecord::Base.logger = Logger.new(File.dirname(__FILE__) + "/debug.log")
db_adapter = ENV['DB']
# no db passed, try one of these fine config-free DBs before bombing.
db_adapter ||=
begin
require 'rubygems'
require 'sqlite'
'sqlite'
rescue MissingSourceFile
begin
require 'sqlite3'
'sqlite3'
rescue MissingSourceFile
end
end
if db_adapter.nil?
raise "No DB Adapter selected. Pass the DB= option to pick one, or install Sqlite or Sqlite3."
end
ActiveRecord::Base.establish_connection(config[db_adapter])
load(File.dirname(__FILE__) + "/schema.rb")
require File.dirname(__FILE__) + '/../rails/init.rb'
end
----------------------------------------------
Now whenever you write a test that requires the database, you can call 'load_schema'.
=== Run the plugin tests ===
Once you have these files in place, you can write your first test to ensure that your plugin-testing setup is correct. By default rails generates a file in 'vendor/plugins/yaffle/test/yaffle_test.rb' with a sample test. Replace the contents of that file with:
*vendor/plugins/yaffle/test/yaffle_test.rb:*
[source, ruby]
----------------------------------------------
require File.dirname(__FILE__) + '/test_helper.rb'
class YaffleTest < Test::Unit::TestCase
load_schema
class Hickwall < ActiveRecord::Base
end
class Wickwall < ActiveRecord::Base
end
def test_schema_has_loaded_correctly
assert_equal [], Hickwall.all
assert_equal [], Wickwall.all
end
end
----------------------------------------------
To run this, go to the plugin directory and run `rake`:
----------------------------------------------
cd vendor/plugins/yaffle
rake
----------------------------------------------
You should see output like:
----------------------------------------------
/opt/local/bin/ruby -Ilib:lib "/opt/local/lib/ruby/gems/1.8/gems/rake-0.8.3/lib/rake/rake_test_loader.rb" "test/yaffle_test.rb"
-- create_table(:hickwalls, {:force=>true})
-> 0.0220s
-- create_table(:wickwalls, {:force=>true})
-> 0.0077s
-- initialize_schema_migrations_table()
-> 0.0007s
-- assume_migrated_upto_version(0)
-> 0.0007s
Loaded suite /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.3/lib/rake/rake_test_loader
Started
.
Finished in 0.002236 seconds.
1 test, 1 assertion, 0 failures, 0 errors
----------------------------------------------
By default the setup above runs your tests with sqlite or sqlite3. To run tests with one of the other connection strings specified in database.yml, pass the DB environment variable to rake:
----------------------------------------------
rake DB=sqlite
rake DB=sqlite3
rake DB=mysql
rake DB=postgresql
----------------------------------------------
Now you are ready to test-drive your plugin!

View file

@ -13,6 +13,8 @@ This guide covers the +find+ method defined in +ActiveRecord::Base+, as well as
If you're used to using raw SQL to find database records, you'll find that there are generally better ways to carry out the same operations in Rails. Active Record insulates you from the need to use SQL in most cases.
The SQL in your log may have some quoting, and that quoting depends on the backend (MySQL, for example, puts backticks around field and table names). Attempting to copy the raw SQL contained within this guide may not work in your database system. Please consult the database systems manual before attempting to execute any SQL.
== The Sample Models
This guide demonstrates finding using the following models:
@ -52,16 +54,16 @@ Active Record will perform queries on the database for you and is compatible wit
[source, sql]
-------------------------------------------------------
SELECT * FROM +clients+ WHERE (+clients+.+id+ = 1)
SELECT * FROM clients WHERE (clients.id = 1)
-------------------------------------------------------
NOTE: Because this is a standard table created from a migration in Rail, the primary key is defaulted to 'id'. If you have specified a different primary key in your migrations, this is what Rails will find on when you call the find method, not the id column.
NOTE: Because this is a standard table created from a migration in Rails, the primary key is defaulted to 'id'. If you have specified a different primary key in your migrations, this is what Rails will find on when you call the find method, not the id column.
If you wanted to find clients with id 1 or 2, you call +Client.find([1,2])+ or +Client.find(1,2)+ and then this will be executed as:
[source, sql]
-------------------------------------------------------
SELECT * FROM +clients+ WHERE (+clients+.+id+ IN (1,2))
SELECT * FROM clients WHERE (clients.id IN (1,2))
-------------------------------------------------------
-------------------------------------------------------
@ -76,7 +78,7 @@ Note that if you pass in a list of numbers that the result will be returned as a
NOTE: If +find(id)+ or +find([id1, id2])+ fails to find any records, it will raise a +RecordNotFound+ exception.
If you wanted to find the first client you would simply type +Client.first+ and that would find the first client created in your clients table:
If you wanted to find the first Client object you would simply type +Client.first+ and that would find the first client in your clients table:
-------------------------------------------------------
>> Client.first
@ -84,7 +86,7 @@ If you wanted to find the first client you would simply type +Client.first+ and
created_at: "2008-09-28 15:38:50", updated_at: "2008-09-28 15:38:50">
-------------------------------------------------------
If you were running script/server you might see the following output:
If you were reading your log file (the default is log/development.log) you may see something like this:
[source,sql]
-------------------------------------------------------
@ -93,20 +95,29 @@ SELECT * FROM clients LIMIT 1
Indicating the query that Rails has performed on your database.
To find the last client you would simply type +Client.find(:last)+ and that would find the last client created in your clients table:
To find the last Client object you would simply type +Client.last+ and that would find the last client created in your clients table:
-------------------------------------------------------
>> Client.find(:last)
>> Client.last
=> #<Client id: 2, name: => "Michael", locked: false, orders_count: 3,
created_at: "2008-09-28 13:12:40", updated_at: "2008-09-28 13:12:40">
-------------------------------------------------------
If you were reading your log file (the default is log/development.log) you may see something like this:
[source,sql]
-------------------------------------------------------
SELECT * FROM clients ORDER BY id DESC LIMIT 1
-------------------------------------------------------
NOTE: Please be aware that the syntax that Rails uses to find the first record in the table means that it may not be the actual first record. If you want the actual first record based on a field in your table (e.g. +created_at+) specify an order option in your find call. The last method call works differently: it finds the last record on your table based on the primary key column.
[source,sql]
-------------------------------------------------------
SELECT * FROM clients ORDER BY clients.id DESC LIMIT 1
-------------------------------------------------------
To find all the clients you would simply type +Client.all+ and that would find all the clients in your clients table:
To find all the Client objects you would simply type +Client.all+ and that would find all the clients in your clients table:
-------------------------------------------------------
>> Client.all
@ -114,11 +125,11 @@ To find all the clients you would simply type +Client.all+ and that would find a
created_at: "2008-09-28 15:38:50", updated_at: "2008-09-28 15:38:50">,
#<Client id: 2, name: => "Michael", locked: false, orders_count: 3,
created_at: "2008-09-28 13:12:40", updated_at: "2008-09-28 13:12:40">]
-------------------------------------------------------
-------------------------------------------------------
As alternatives to calling +Client.first+, +Client.last+, and +Client.all+, you can use the class methods +Client.first+, +Client.last+, and +Client.all+ instead. +Client.first+, +Client.last+ and +Client.all+ just call their longer counterparts: +Client.find(:first)+, +Client.find(:last)+ and +Client.find(:all)+ respectively.
You may see in Rails code that there are calls to methods such as +Client.find(:all)+, +Client.find(:first)+ and +Client.find(:last)+. These methods are just alternatives to +Client.all+, +Client.first+ and +Client.last+ respectively.
Be aware that +Client.first+/+Client.find(:first)+ and +Client.last+/+Client.find(:last)+ will both return a single object, where as +Client.all+/+Client.find(:all)+ will return an array of Client objects, just as passing in an array of ids to find will do also.
Be aware that +Client.first+/+Client.find(:first)+ and +Client.last+/+Client.find(:last)+ will both return a single object, where as +Client.all+/+Client.find(:all)+ will return an array of Client objects, just as passing in an array of ids to +find+ will do also.
== Conditions
@ -132,19 +143,20 @@ WARNING: Building your own conditions as pure strings can leave you vulnerable t
=== Array Conditions ===
Now what if that number could vary, say as a parameter from somewhere, or perhaps from the user's level status somewhere? The find then becomes something like +Client.first(:conditions => ["orders_count = ?", params[:orders]])+. Active Record will go through the first element in the conditions value and any additional elements will replace the question marks (?) in the first element. If you want to specify two conditions, you can do it like +Client.first(:conditions => ["orders_count = ? AND locked = ?", params[:orders], false])+. In this example, the first question mark will be replaced with the value in params orders and the second will be replaced with true and this will find the first record in the table that has '2' as its value for the orders_count field and 'false' for its locked field.
Now what if that number could vary, say as a parameter from somewhere, or perhaps from the user's level status somewhere? The find then becomes something like +Client.first(:conditions => ["orders_count = ?", params[:orders]])+. Active Record will go through the first element in the conditions value and any additional elements will replace the question marks (?) in the first element. If you want to specify two conditions, you can do it like +Client.first(:conditions => ["orders_count = ? AND locked = ?", params[:orders], false])+. In this example, the first question mark will be replaced with the value in +params[:orders]+ and the second will be replaced with +false+ and this will find the first record in the table that has '2' as its value for the +orders_count+ field and +false+ for its locked field.
The reason for doing code like:
[source, ruby]
-------------------------------------------------------
+Client.first(:conditions => ["orders_count = ?", params[:orders]])+
Client.first(:conditions => ["orders_count = ?", params[:orders]])
-------------------------------------------------------
instead of:
[source, ruby]
-------------------------------------------------------
+Client.first(:conditions => "orders_count = #{params[:orders]}")+
Client.first(:conditions => "orders_count = #{params[:orders]}")
-------------------------------------------------------
is because of parameter safety. Putting the variable directly into the conditions string will pass the variable to the database *as-is*. This means that it will be an unescaped variable directly from a user who may have malicious intent. If you do this, you put your entire database at risk because once a user finds out he or she can exploit your database they can do just about anything to it. Never ever put your parameters directly inside the conditions string.
@ -163,7 +175,7 @@ This would generate the proper query which is great for small ranges but not so
[source, sql]
-------------------------------------------------------
SELECT * FROM +users+ WHERE (created_at IN
SELECT * FROM users WHERE (created_at IN
('2007-12-31','2008-01-01','2008-01-02','2008-01-03','2008-01-04','2008-01-05',
'2008-01-06','2008-01-07','2008-01-08','2008-01-09','2008-01-10','2008-01-11',
'2008-01-12','2008-01-13','2008-01-14','2008-01-15','2008-01-16','2008-01-17',
@ -183,7 +195,7 @@ Client.all(:conditions => ["created_at IN (?)",
[source, sql]
-------------------------------------------------------
SELECT * FROM +users+ WHERE (created_at IN
SELECT * FROM users WHERE (created_at IN
('2007-12-01 00:00:00', '2007-12-01 00:00:01' ...
'2007-12-01 23:59:59', '2007-12-02 00:00:00'))
-------------------------------------------------------
@ -214,7 +226,7 @@ Client.all(:conditions =>
Just like in Ruby.
=== Hash Conditions ===
=== Placeholder Conditions ===
Similar to the array style of params you can also specify keys in your conditions:
@ -234,6 +246,8 @@ If you're getting a set of records and want to force an order, you can use +Clie
To select certain fields, you can use the select option like this: +Client.first(:select => "viewable_by, locked")+. This select option does not use an array of fields, but rather requires you to type SQL-like code. The above code will execute +SELECT viewable_by, locked FROM clients LIMIT 0,1+ on your database.
You can also call SQL functions within the select option. For example, if you would like to only grab a single record per unique value in a certain field by using the +DISTINCT+ function you can do it like this: +Client.all(:select => "DISTINCT(name)")+.
== Limit & Offset
If you want to limit the amount of records to a certain subset of all the records retrieved you usually use limit for this, sometimes coupled with offset. Limit is the maximum number of records that will be retrieved from a query, and offset is the number of records it will start reading from from the first record of the set. Take this code for example:
@ -277,7 +291,7 @@ The SQL that would be executed would be something like this:
[source, sql]
-------------------------------------------------------
SELECT * FROM +orders+ GROUP BY date(created_at)
SELECT * FROM orders GROUP BY date(created_at)
-------------------------------------------------------
== Read Only
@ -357,20 +371,27 @@ Client.first(:include => "orders", :conditions =>
== Dynamic finders
For every field (also known as an attribute) you define in your table, Active Record provides a finder method. If you have a field called +name+ on your Client model for example, you get +find_by_name+ and +find_all_by_name+ for free from Active Record. If you have also have a +locked+ field on the client model, you also get +find_by_locked+ and +find_all_by_locked+. If you want to find both by name and locked, you can chain these finders together by simply typing +and+ between the fields for example +Client.find_by_name_and_locked('Ryan', true)+. These finders are an excellent alternative to using the conditions option, mainly because it's shorter to type +find_by_name(params[:name])+ than it is to type +first(:conditions => ["name = ?", params[:name]])+.
For every field (also known as an attribute) you define in your table, Active Record provides a finder method. If you have a field called +name+ on your Client model for example, you get +find_by_name+ and +find_all_by_name+ for free from Active Record. If you have also have a +locked+ field on the client model, you also get +find_by_locked+ and +find_all_by_locked+.
You can do +find_last_by_*+ methods too which will find the last record matching your parameter.
You can specify an exclamation point (!) on the end of the dynamic finders to get them to raise an +ActiveRecord::RecordNotFound+ error if they do not return any records, like +Client.find_by_name!('Ryan')+
If you want to find both by name and locked, you can chain these finders together by simply typing +and+ between the fields for example +Client.find_by_name_and_locked('Ryan', true)+.
There's another set of dynamic finders that let you find or create/initialize objects if they aren't find. These work in a similar fashion to the other finders and can be used like +find_or_create_by_name(params[:name])+. Using this will firstly perform a find and then create if the find returns nil. The SQL looks like this for +Client.find_or_create_by_name('Ryan')+:
[source,sql]
-------------------------------------------------------
SELECT * FROM +clients+ WHERE (+clients+.+name+ = 'Ryan') LIMIT 1
SELECT * FROM clients WHERE (clients.name = 'Ryan') LIMIT 1
BEGIN
INSERT INTO +clients+ (+name+, +updated_at+, +created_at+, +orders_count+, +locked+)
INSERT INTO clients (name, updated_at, created_at, orders_count, locked)
VALUES('Ryan', '2008-09-28 15:39:12', '2008-09-28 15:39:12', '0', '0')
COMMIT
-------------------------------------------------------
+find_or_create+'s sibling, +find_or_initialize+, will find an object and if it does not exist will call +new+ with the parameters you passed in. For example:
+find_or_create+'s sibling, +find_or_initialize+, will find an object and if it does not exist will act similar to calling +new+ with the parameters you passed in. For example:
[source, ruby]
-------------------------------------------------------
@ -379,6 +400,7 @@ client = Client.find_or_initialize_by_name('Ryan')
will either assign an existing client object with the name 'Ryan' to the client local variable, or initialize new object similar to calling +Client.new(:name => 'Ryan')+. From here, you can modify other fields in client by calling the attribute setters on it: +client.locked = true+ and when you want to write it to the database just call +save+ on it.
== Finding By SQL
If you'd like to use your own SQL to find records a table you can use +find_by_sql+. The +find_by_sql+ method will return an array of objects even if it only returns a single record in it's call to the database. For example you could run this query:
@ -571,7 +593,7 @@ Which will execute:
[source, sql]
-------------------------------------------------------
SELECT count(*) AS count_all FROM +clients+ WHERE (first_name = 1)
SELECT count(*) AS count_all FROM clients WHERE (first_name = 1)
-------------------------------------------------------
You can also use +include+ or +joins+ for this to do something a little more complex:
@ -585,8 +607,8 @@ Which will execute:
[source, sql]
-------------------------------------------------------
SELECT count(DISTINCT +clients+.id) AS count_all FROM +clients+
LEFT OUTER JOIN +orders+ ON orders.client_id = client.id WHERE
SELECT count(DISTINCT clients.id) AS count_all FROM clients
LEFT OUTER JOIN orders ON orders.client_id = client.id WHERE
(clients.first_name = 'name' AND orders.status = 'received')
-------------------------------------------------------
@ -655,6 +677,10 @@ Thanks to Mike Gunderloy for his tips on creating this guide.
http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16[Lighthouse ticket]
* December 1 2008: Added using an SQL function example to Selecting Certain Fields section as per http://rails.lighthouseapp.com/projects/16213/tickets/36-adding-an-example-for-using-distinct-to-ar-finders[this ticket]
* November 23 2008: Added documentation for +find_by_last+ and +find_by_bang!+
* November 21 2008: Fixed all points specified in http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16-activerecord-finders#ticket-16-13[this comment] and http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16-activerecord-finders#ticket-16-14[this comment]
* November 18 2008: Fixed all points specified in http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16-activerecord-finders#ticket-16-11[this comment]
* November 8, 2008: Editing pass by link:../authors.html#mgunderloy[Mike Gunderloy] . First release version.
* October 27, 2008: Added scoped section, added named params for conditions and added sub-section headers for conditions section by Ryan Bigg
* October 27, 2008: Fixed up all points specified in http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16-activerecord-finders#ticket-16-6[this comment] with an exception of the final point by Ryan Bigg

View file

@ -154,6 +154,13 @@ And if you're using PostgreSQL for data storage, run this command:
$ rails blog -d postgresql
-------------------------------------------------------
After you create the blog application, switch to its folder to continue work directly in that application:
[source, shell]
-------------------------------------------------------
$ cd blog
-------------------------------------------------------
In any case, Rails will create a folder in your working directory called +blog+. Open up that folder and explore its contents. Most of the work in this tutorial will happen in the +app/+ folder, but here's a basic rundown on the function of each folder that Rails creates in a new application by default:
[grid="all"]
@ -239,6 +246,15 @@ development:
Change the username and password in the +development+ section as appropriate.
==== Creating the Database
Now that you have your database configured, it's time to have Rails create an empty database for you. You can do this by running a rake command:
[source, shell]
-------------------------------------------------------
$ rake db:create
-------------------------------------------------------
== Hello, Rails!
One of the traditional places to start with a new language is by getting some text up on screen quickly. To do that in Rails, you need to create at minimum a controller and a view. Fortunately, you can do that in a single command. Enter this command in your terminal:
@ -370,7 +386,7 @@ end
If you were to translate that into words, it says something like: when this migration is run, create a table named +posts+ with two string columns (+name+ and +title+) and a text column (+content+), and generate timestamp fields to track record creation and updating. You can learn the detailed syntax for migrations in the link:../migrations.html[Rails Database Migrations] guide.
At this point, you need to do two things: create the database and run the migration. You can use rake commands at the terminal for both of those tasks:
At this point, you can use a rake command to run the migration:
[source, shell]
-------------------------------------------------------
@ -378,7 +394,7 @@ $ rake db:create
$ rake db:migrate
-------------------------------------------------------
NOTE: Because you're working in the development environment by default, both of these commands will apply to the database defined in the +development+ section of your +config/database.yml+ file.
NOTE: Because you're working in the development environment by default, this command will apply to the database defined in the +development+ section of your +config/database.yml+ file.
=== Adding a Link
@ -748,7 +764,7 @@ At this point, its worth looking at some of the tools that Rails provides to
=== Using Partials to Eliminate View Duplication
As you saw earlier, the scaffold-generated views for the +new+ and +edit+ actions are largely identical. You can pull the shared code out into a +partial+ template. This requires editing the new and edit views, and adding a new template:
As you saw earlier, the scaffold-generated views for the +new+ and +edit+ actions are largely identical. You can pull the shared code out into a +partial+ template. This requires editing the new and edit views, and adding a new template. The new +_form.html.erb+ template should be saved in the same +app/views/posts+ folder as the files from which it is being extracted:
+new.html.erb+:
@ -1021,7 +1037,7 @@ class CommentsController < ApplicationController
def show
@post = Post.find(params[:post_id])
@comment = Comment.find(params[:id])
@comment = @post.comments.find(params[:id])
end
def new
@ -1033,7 +1049,7 @@ class CommentsController < ApplicationController
@post = Post.find(params[:post_id])
@comment = @post.comments.build(params[:comment])
if @comment.save
redirect_to post_comment_path(@post, @comment)
redirect_to post_comment_url(@post, @comment)
else
render :action => "new"
end
@ -1041,14 +1057,14 @@ class CommentsController < ApplicationController
def edit
@post = Post.find(params[:post_id])
@comment = Comment.find(params[:id])
@comment = @post.comments.find(params[:id])
end
def update
@post = Post.find(params[:post_id])
@comment = Comment.find(params[:id])
if @comment.update_attributes(params[:comment])
redirect_to post_comment_path(@post, @comment)
redirect_to post_comment_url(@post, @comment)
else
render :action => "edit"
end
@ -1219,7 +1235,7 @@ Note that each post has its own individual comments collection, accessible as +@
Now that you've seen your first Rails application, you should feel free to update it and experiment on your own. But you don't have to do everything without help. As you need assistance getting up and running with Rails, feel free to consult these support resources:
* The link:http://manuals.rubyonrails.org/[Ruby On Rails guides]
* The link:http://guides.rubyonrails.org/[Ruby On Rails guides]
* The link:http://groups.google.com/group/rubyonrails-talk[Ruby on Rails mailing list]
* The #rubyonrails channel on irc.freenode.net
* The link:http://wiki.rubyonrails.org/rails[Rails wiki]

View file

@ -0,0 +1,542 @@
The Rails Internationalization API
==================================
The Ruby I18n gem which is shipped with Ruby on Rails (starting from Rails 2.2) provides an easy-to-use and extensible framework for translating your application to a single custom language other than English or providing multi-language support in your application.
== How I18n in Ruby on Rails works
Internationalization is a complex problem. Natural languages differ in so many ways that it is hard to provide tools for solving all problems at once. For that reason the Rails I18n API focusses on:
* providing support for English and similar languages out of the box
* making it easy to customize and extend everything for other languages
=== The overall architecture of the library
To solve this the Ruby I18n gem is split into two parts:
* The public API which is just a Ruby module with a bunch of public methods and definitions how the library works.
* A shipped backend (which is intentionally named the Simple backend) that implements these methods.
As a user you should always only access the public methods on the I18n module but it is useful to know about the capabilities of the backend you use and maybe exchange the shipped Simple backend with a more powerful one.
=== The public I18n API
We will go into more detail about the public methods later but here's a quick overview. The most important methods are:
[source, ruby]
-------------------------------------------------------
translate # lookup translations
localize # localize Date and Time objects to local formats
-------------------------------------------------------
There are also attribute readers and writers for the following attributes:
[source, ruby]
-------------------------------------------------------
load_path # announce your custom translation files
locale # get and set the current locale
default_locale # get and set the default locale
exception_handler # use a different exception_handler
backend # use a different backend
-------------------------------------------------------
== Walkthrough: setup a simple I18n'ed Rails application
There are just a few, simple steps to get up and running with a I18n support for your application.
=== Configure the I18n module
First of all you want to tell the I18n library where it can find your custom translation files. You might also want to set your default locale to something else than English.
You can pick whatever directory and translation file naming scheme makes sense for you. The simplest thing possible is probably to put the following into an initializer:
[source, ruby]
-------------------------------------------------------
# in config/initializer/locale.rb
# tell the I18n library where to find your translations
I18n.load_path += Dir[ File.join(RAILS_ROOT, 'lib', 'locale', '*.{rb,yml}') ]
# you can omit this if you're happy with English as a default locale
I18n.default_locale = :"pt"
-------------------------------------------------------
I18n.load_path is just a Ruby Array of paths to your translation files. The backend will lazy-load these translations when a translation is looked up for the first time. This makes it possible to just swap the backend with something else even after translations have already been announced.
=== Set the locale in each request
By default the I18n library will use the I18n.default_locale for looking up translations (if you do not specify a locale for a lookup) and this will, by default, en (English).
If you want to translate your Rails application to a single language other than English you can set I18n.default_locale to your locale. If you want to change the locale on a per-request basis though you can set it in a before_filter on the ApplicationController like this:
[source, ruby]
-------------------------------------------------------
before_filter :set_locale
def set_locale
# if this is nil then I18n.default_locale will be used
I18n.locale = params[:locale]
end
-------------------------------------------------------
This will already work for URLs where you pass the locale as a query parameter as in example.com?locale=pt-BR (which is what Google also does). (TODO hints about other approaches in the resources section).
Now you've initialized I18n support for your application and told it which locale should be used. With that in place you're now ready for the really interesting stuff.
=== Internationalize your application
The process of "internationalization" usually means to abstract all strings and other locale specific bits out of your application (TODO reference to wikipedia). The process of "localization" means to then provide translations and localized formats for these bits.
So, let's internationalize something. You most probably have something like this in one of your applications:
[source, ruby]
-------------------------------------------------------
# config/routes.rb
ActionController::Routing::Routes.draw do |map|
map.root :controller => 'home', :action => 'index'
end
# app/controllers/home_controller.rb
class HomeController < ApplicationController
def index
flash[:notice] = "Hello flash!"
end
end
# app/views/home/index.html.erb
<h1>Hello world!</h1>
<p><%= flash[:notice] %></p>
-------------------------------------------------------
TODO screenshot
Obviously there are two strings that are localized to English. In order to internationalize this code replace these strings with calls to Rails' #t helper with a key that makes sense for the translation:
[source, ruby]
-------------------------------------------------------
# app/controllers/home_controller.rb
class HomeController < ApplicationController
def index
flash[:notice] = t(:hello_flash)
end
end
# app/views/home/index.html.erb
<h1><%=t :hello_world %></h1>
<p><%= flash[:notice] %></p>
-------------------------------------------------------
TODO insert note about #t helper compared to I18n.t
TODO insert note/reference about structuring translation keys
When you now render this view it will show an error message that tells you that the translations for the keys :hello_world and :hello_flash are missing.
TODO screenshot
So let's add the missing translations (i.e. do the "localization" part):
[source, ruby]
-------------------------------------------------------
# lib/locale/en.yml
en-US:
hello_world: Hello World
hello_flash: Hello Flash
# lib/locale/pirate.yml
pirate:
hello_world: Ahoy World
hello_flash: Ahoy Flash
-------------------------------------------------------
There you go. Your application now shows:
TODO screenshot
[source, ruby]
-------------------------------------------------------
I18n.t 'store.title'
I18n.l Time.now
-------------------------------------------------------
== Overview of the I18n API features
The following purposes are covered:
* lookup translations
* interpolate data into translations
* pluralize translations
* localize dates, numbers, currency etc.
=== Looking up translations
==== Basic lookup, scopes and nested keys
Translations are looked up by keys which can be both Symbols or Strings, so these calls are equivalent:
[source, ruby]
-------------------------------------------------------
I18n.t :message
I18n.t 'message'
-------------------------------------------------------
translate also takes a :scope option which can contain one or many additional keys that will be used to specify a “namespace” or scope for a translation key:
[source, ruby]
-------------------------------------------------------
I18n.t :invalid, :scope => [:active_record, :error_messages]
-------------------------------------------------------
This looks up the :invalid message in the ActiveRecord error messages.
Additionally, both the key and scopes can be specified as dot separated keys as in:
[source, ruby]
-------------------------------------------------------
I18n.translate :"active_record.error_messages.invalid"
-------------------------------------------------------
Thus the following calls are equivalent:
[source, ruby]
-------------------------------------------------------
I18n.t 'active_record.error_messages.invalid'
I18n.t 'error_messages.invalid', :scope => :active_record
I18n.t :invalid, :scope => 'active_record.error_messages'
I18n.t :invalid, :scope => [:active_record, :error_messages]
-------------------------------------------------------
==== Defaults
When a default option is given its value will be returned if the translation is missing:
[source, ruby]
-------------------------------------------------------
I18n.t :missing, :default => 'Not here'
# => 'Not here'
-------------------------------------------------------
If the default value is a Symbol it will be used as a key and translated. One can provide multiple values as default. The first one that results in a value will be returned.
E.g. the following first tries to translate the key :missing and then the key :also_missing. As both do not yield a result the string Not here will be returned:
[source, ruby]
-------------------------------------------------------
I18n.t :missing, :default => [:also_missing, 'Not here']
# => 'Not here'
-------------------------------------------------------
==== Bulk and namespace lookup
To lookup multiple translations at once an array of keys can be passed:
[source, ruby]
-------------------------------------------------------
I18n.t [:odd, :even], :scope => 'active_record.error_messages'
# => ["must be odd", "must be even"]
-------------------------------------------------------
Also, a key can translate to a (potentially nested) hash as grouped translations. E.g. one can receive all ActiveRecord error messages as a Hash with:
[source, ruby]
-------------------------------------------------------
I18n.t 'active_record.error_messages'
# => { :inclusion => "is not included in the list", :exclusion => ... }
-------------------------------------------------------
=== Interpolation
TODO explain what this is good for
All options besides :default and :scope that are passed to #translate will be interpolated to the translation:
[source, ruby]
-------------------------------------------------------
I18n.backend.store_translations 'en', :thanks => 'Thanks {{name}}!'
I18n.translate :thanks, :name => 'Jeremy'
# => 'Thanks Jeremy!'
-------------------------------------------------------
If a translation uses :default or :scope as a interpolation variable an I18n::ReservedInterpolationKey exception is raised. If a translation expects an interpolation variable but it has not been passed to #translate an I18n::MissingInterpolationArgument exception is raised.
=== Pluralization
TODO explain what this is good for
The :count interpolation variable has a special role in that it both is interpolated to the translation and used to pick a pluralization from the translations according to the pluralization rules defined by CLDR:
[source, ruby]
-------------------------------------------------------
I18n.backend.store_translations 'en-US', :inbox => { # TODO change this
:one => '1 message',
:other => '{{count}} messages'
}
I18n.translate :inbox, :count => 2
# => '2 messages'
-------------------------------------------------------
The algorithm for pluralizations in en-US is as simple as:
[source, ruby]
-------------------------------------------------------
entry[count == 1 ? 0 : 1]
-------------------------------------------------------
I.e. the translation denoted as :one is regarded as singular, the other is used as plural (including the count being zero).
If the lookup for the key does not return an Hash suitable for pluralization an I18n::InvalidPluralizationData exception is raised.
=== Setting and passing a locale
The locale can be either set pseudo-globally to I18n.locale (which uses Thread.current like, e.g., Time.zone) or can be passed as an option to #translate and #localize.
If no locale is passed I18n.locale is used:
[source, ruby]
-------------------------------------------------------
I18n.locale = :'de'
I18n.t :foo
I18n.l Time.now
-------------------------------------------------------
Explicitely passing a locale:
[source, ruby]
-------------------------------------------------------
I18n.t :foo, :locale => :'de'
I18n.l Time.now, :locale => :'de'
-------------------------------------------------------
I18n.locale defaults to I18n.default_locale which defaults to :'en'. The default locale can be set like this:
[source, ruby]
-------------------------------------------------------
I18n.default_locale = :'de'
-------------------------------------------------------
== How to store your custom translations
The shipped Simple backend allows you to store translations in both plain Ruby and YAML format. (2)
For example a Ruby Hash providing translations can look like this:
[source, ruby]
-------------------------------------------------------
{
:'pt-BR' => {
:foo => {
:bar => "baz"
}
}
}
-------------------------------------------------------
The equivalent YAML file would look like this:
[source, ruby]
-------------------------------------------------------
"pt-BR":
foo:
bar: baz
-------------------------------------------------------
As you see in both cases the toplevel key is the locale. :foo is a namespace key and :bar is the key for the translation "baz".
Here is a "real" example from the ActiveSupport en-US translations YAML file:
[source, ruby]
-------------------------------------------------------
"en":
date:
formats:
default: "%Y-%m-%d"
short: "%b %d"
long: "%B %d, %Y"
-------------------------------------------------------
So, all of the following equivalent lookups will return the :short date format "%B %d":
[source, ruby]
-------------------------------------------------------
I18n.t 'date.formats.short'
I18n.t 'formats.short', :scope => :date
I18n.t :short, :scope => 'date.formats'
I18n.t :short, :scope => [:date, :formats]
-------------------------------------------------------
=== Translations for ActiveRecord models
You can use the methods Model.human_name and Model.human_attribute_name(attribute) to transparently lookup translations for your model and attribute names.
For example when you add the following translations:
en:
activerecord:
models:
user: Dude
attributes:
user:
login: "Handle"
# will translate User attribute "login" as "Handle"
Then User.human_name will return "Dude" and User.human_attribute_name(:login) will return "Handle".
==== Error message scopes
ActiveRecord validation error messages can also be translated easily. ActiveRecord gives you a couple of namespaces where you can place your message translations in order to provide different messages and translation for certain models, attributes and/or validations. It also transparently takes single table inheritance into account.
This gives you quite powerful means to flexibly adjust your messages to your application's needs.
Consider a User model with a validates_presence_of validation for the name attribute like this:
[source, ruby]
-------------------------------------------------------
class User < ActiveRecord::Base
validates_presence_of :name
end
-------------------------------------------------------
The key for the error message in this case is :blank. So ActiveRecord will first try to look up an error message with:
[source, ruby]
-------------------------------------------------------
activerecord.errors.messages.models.user.attributes.name.blank
-------------------------------------------------------
If it's not there it will try:
[source, ruby]
-------------------------------------------------------
activerecord.errors.messages.models.user.blank
-------------------------------------------------------
If this is also not there it will use the default message from:
[source, ruby]
-------------------------------------------------------
activerecord.errors.messages.blank
-------------------------------------------------------
When your models are additionally using inheritance then the messages are looked up for the inherited model class names are looked up.
For example, you might have an Admin model inheriting from User:
[source, ruby]
-------------------------------------------------------
class Admin < User
validates_presence_of :name
end
-------------------------------------------------------
Then ActiveRecord will look for messages in this order:
[source, ruby]
-------------------------------------------------------
activerecord.errors.models.admin.attributes.title.blank
activerecord.errors.models.admin.blank
activerecord.errors.models.user.attributes.title.blank
activerecord.errors.models.user.blank
activerecord.errors.messages.blank
-------------------------------------------------------
This way you can provide special translations for various error messages at different points in your models inheritance chain and in the attributes, models or default scopes.
==== Error message interpolation
The translated model name and translated attribute name are always available for interpolation.
So, for example, instead of the default error message "can not be blank" you could use the attribute name like this: "Please fill in your {{attribute}}".
Count and/or value are available where applicable. Count can be used for pluralization if present:
[grid="all"]
`---------------------------`----------------`---------------`----------------
validation with option message interpolation
validates_confirmation_of - :confirmation -
validates_acceptance_of - :accepted -
validates_presence_of - :blank -
validates_length_of :within, :in :too_short count
validates_length_of :within, :in :too_long count
validates_length_of :is :wrong_length count
validates_length_of :minimum :too_short count
validates_length_of :maximum :too_long count
validates_uniqueness_of - :taken value
validates_format_of - :invalid value
validates_inclusion_of - :inclusion value
validates_exclusion_of - :exclusion value
validates_associated - :invalid value
validates_numericality_of - :not_a_number value
validates_numericality_of :odd :odd value
validates_numericality_of :even :even value
------------------------------------------------------------------------------
==== Translations for the ActiveRecord error_messages_for helper
If you are using the ActiveRecord error_messages_for helper you will want to add translations for it.
Rails ships with the following translations:
[source, ruby]
-------------------------------------------------------
"en":
activerecord:
errors:
template:
header:
one: "1 error prohibited this {{model}} from being saved"
other: "{{count}} errors prohibited this {{model}} from being saved"
body: "There were problems with the following fields:"
-------------------------------------------------------
=== Other translations and localizations
Rails uses fixed strings and other localizations, such as format strings and other format information in a couple of helpers.
TODO list helpers and available keys
== Customize your I18n setup
=== Using different backends
For several reasons the shipped Simple backend only does the "simplest thing that ever could work" _for Ruby on Rails_ (1) ... which means that it is only guaranteed to work for English and, as a side effect, languages that are very similar to English. Also, the simple backend is only capable of reading translations but can not dynamically store them to any format.
That does not mean you're stuck with these limitations though. The Ruby I18n gem makes it very easy to exchange the Simple backend implementation with something else that fits better for your needs. E.g. you could exchange it with Globalize's Static backend:
[source, ruby]
-------------------------------------------------------
I18n.backend = Globalize::Backend::Static.new
-------------------------------------------------------
TODO expand this ...? list some backends and their features?
=== Using different exception handlers
TODO
* Explain what exceptions are raised and why we are using exceptions for communication from backend to frontend.
* Explain the default behaviour.
* Explain the :raise option
* Example 1: the Rails #t helper uses a custom exception handler that catches I18n::MissingTranslationData and wraps the message into a span with the CSS class "translation_missing"
* Example 2: for tests you might want a handler that just raises all exceptions all the time
* Example 3: a handler
== Resources
* http://rails-i18n.org
== Footnotes
(1) One of these reasons is that we don't want to any unnecessary load for applications that do not need any I18n capabilities, so we need to keep the I18n library as simple as possible for English. Another reason is that it is virtually impossible to implement a one-fits-all solution for all problems related to I18n for all existing languages. So a solution that allows us to exchange the entire implementation easily is appropriate anyway. This also makes it much easier to experiment with custom features and extensions.
(2) Other backends might allow or require to use other formats, e.g. a GetText backend might allow to read GetText files.
== Credits
== NOTES
How to contribute?

View file

@ -113,6 +113,16 @@ This guide covers ways to analyze and optimize your running Rails code.
This guide covers how to build a plugin to extend the functionality of Rails.
***********************************************************
.link:i18n.html[The Rails Internationalization API]
***********************************************************
CAUTION: still a basic draft
This guide introduces you to the basic concepts and features of the Rails I18n API and shows you how to localize your application.
***********************************************************
Authors who have contributed to complete guides are listed link:authors.html[here].
This work is licensed under a link:http://creativecommons.org/licenses/by-nc-sa/3.0/[Creative Commons Attribution-Noncommercial-Share Alike 3.0 License]

View file

@ -1,7 +1,7 @@
Migrations
==========
Migrations are a convenient way for you to alter your database in a structured and organised manner. You could edit fragments of SQL by hand but you would then be responsible for telling other developers that they need to go and run it. You'd also have to keep track of which changes need to be run against the production machines next time you deploy. Active Record tracks which migrations have already been run so all you have to do is update your source and run `rake db:migrate`. Active Record will work out which migrations should be run.
Migrations are a convenient way for you to alter your database in a structured and organised manner. You could edit fragments of SQL by hand but you would then be responsible for telling other developers that they need to go and run it. You'd also have to keep track of which changes need to be run against the production machines next time you deploy. Active Record tracks which migrations have already been run so all you have to do is update your source and run `rake db:migrate`. Active Record will work out which migrations should be run. It will also update your db/schema.rb file to match the structure of your database.
Migrations also allow you to describe these transformations using Ruby. The great thing about this is that (like most of Active Record's functionality) it is database independent: you don't need to worry about the precise syntax of CREATE TABLE any more that you worry about variations on SELECT * (you can drop down to raw SQL for database specific features). For example you could use SQLite3 in development, but MySQL in production.

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@ -2,6 +2,8 @@
Rails provides a set of rake tasks to work with migrations which boils down to running certain sets of migrations. The very first migration related rake task you use will probably be `db:migrate`. In its most basic form it just runs the `up` method for all the migrations that have not yet been run. If there are no such migrations it exits.
Note that running the `db:migrate` also invokes the `db:schema:dump` task, which will update your db/schema.rb file to match the structure of your database.
If you specify a target version, Active Record will run the required migrations (up or down) until it has reached the specified version. The
version is the numerical prefix on the migration's filename. For example to migrate to version 20080906120000 run

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@ -424,7 +424,7 @@ In this case, all of the normal routes except the route for +destroy+ (a +DELETE
In addition to an action or a list of actions, you can also supply the special symbols +:all+ or +:none+ to the +:only+ and +:except+ options.
TIP: If your application has many RESTful routes, using +:only+ and +:accept+ to generate only the routes that you actually need can cut down on memory use and speed up the routing process.
TIP: If your application has many RESTful routes, using +:only+ and +:except+ to generate only the routes that you actually need can cut down on memory use and speed up the routing process.
=== Nested Resources
@ -738,7 +738,7 @@ You do not need to explicitly use the +:controller+ and +:action+ symbols within
[source, ruby]
-------------------------------------------------------
map.connect 'photo/:id', :controller => 'photos', :action => 'show'
map.connect 'photos/:id', :controller => 'photos', :action => 'show'
-------------------------------------------------------
With this route, an incoming URL of +/photos/12+ would be dispatched to the +show+ action within the +Photos+ controller.
@ -747,7 +747,7 @@ You an also define other defaults in a route by supplying a hash for the +:defau
[source, ruby]
-------------------------------------------------------
map.connect 'photo/:id', :controller => 'photos', :action => 'show', :defaults => { :format => 'jpg' }
map.connect 'photos/:id', :controller => 'photos', :action => 'show', :defaults => { :format => 'jpg' }
-------------------------------------------------------
With this route, an incoming URL of +photos/12+ would be dispatched to the +show+ action within the +Photos+ controller, and +params[:format]+ will be set to +jpg+.
@ -886,7 +886,7 @@ For better readability, you can specify an already-created route in your call to
[source, ruby]
-------------------------------------------------------
map.index :controller => "pages", :action => "main"
map.index 'index', :controller => "pages", :action => "main"
map.root :index
-------------------------------------------------------

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@ -97,6 +97,10 @@ ul li {
background-position: 0 0.55em;
}
ul li p {
margin-bottom: 0.5em;
}
/* ----------------------------------------------------------------------------
Structure
---------------------------------------------------------------------------- */

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@ -229,7 +229,7 @@ NOTE: +db:test:prepare+ will fail with an error if db/schema.rb doesn't exists.
==== Rake Tasks for Preparing you Application for Testing ==
[grid="all"]
--------------------------------`----------------------------------------------------
------------------------------------------------------------------------------------
Tasks Description
------------------------------------------------------------------------------------
+rake db:test:clone+ Recreate the test database from the current environment's database schema
@ -239,7 +239,7 @@ Tasks Description
+rake db:test:purge+ Empty the test database.
------------------------------------------------------------------------------------
TIP: You can see all these rake tasks and their descriptions by running +rake --tasks --describe+
TIP: You can see all these rake tasks and their descriptions by running +rake \-\-tasks \-\-describe+
=== Running Tests ===
@ -768,7 +768,7 @@ end
You don't need to set up and run your tests by hand on a test-by-test basis. Rails comes with a number of rake tasks to help in testing. The table below lists all rake tasks that come along in the default Rakefile when you initiate a Rail project.
[grid="all"]
--------------------------------`----------------------------------------------------
------------------------------------------------------------------------------------
Tasks Description
------------------------------------------------------------------------------------
+rake test+ Runs all unit, functional and integration tests. You can also simply run +rake+ as the _test_ target is the default.

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@ -110,7 +110,7 @@ namespace :db do
end
desc "Migrate the database through scripts in db/migrate. Target specific version with VERSION=x. Turn off output with VERBOSE=false."
desc "Migrate the database through scripts in db/migrate and update db/schema.rb by invoking db:schema:dump. Target specific version with VERSION=x. Turn off output with VERBOSE=false."
task :migrate => :environment do
ActiveRecord::Migration.verbose = ENV["VERBOSE"] ? ENV["VERBOSE"] == "true" : true
ActiveRecord::Migrator.migrate("db/migrate/", ENV["VERSION"] ? ENV["VERSION"].to_i : nil)