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git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@1709 5ecf4fe2-1ee6-0310-87b1-e25e094e27de
1432 lines
64 KiB
Ruby
Executable file
1432 lines
64 KiB
Ruby
Executable file
require 'yaml'
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require 'active_record/deprecated_finders'
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module ActiveRecord #:nodoc:
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class ActiveRecordError < StandardError #:nodoc:
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end
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class SubclassNotFound < ActiveRecordError #:nodoc:
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end
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class AssociationTypeMismatch < ActiveRecordError #:nodoc:
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end
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class SerializationTypeMismatch < ActiveRecordError #:nodoc:
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end
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class AdapterNotSpecified < ActiveRecordError # :nodoc:
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end
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class AdapterNotFound < ActiveRecordError # :nodoc:
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end
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class ConnectionNotEstablished < ActiveRecordError #:nodoc:
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end
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class ConnectionFailed < ActiveRecordError #:nodoc:
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end
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class RecordNotFound < ActiveRecordError #:nodoc:
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end
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class StatementInvalid < ActiveRecordError #:nodoc:
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end
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class PreparedStatementInvalid < ActiveRecordError #:nodoc:
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end
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class StaleObjectError < ActiveRecordError #:nodoc:
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end
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class AttributeAssignmentError < ActiveRecordError #:nodoc:
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attr_reader :exception, :attribute
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def initialize(message, exception, attribute)
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@exception = exception
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@attribute = attribute
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@message = message
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end
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end
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class MultiparameterAssignmentErrors < ActiveRecordError #:nodoc:
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attr_reader :errors
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def initialize(errors)
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@errors = errors
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end
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end
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# Active Record objects doesn't specify their attributes directly, but rather infer them from the table definition with
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# which they're linked. Adding, removing, and changing attributes and their type is done directly in the database. Any change
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# is instantly reflected in the Active Record objects. The mapping that binds a given Active Record class to a certain
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# database table will happen automatically in most common cases, but can be overwritten for the uncommon ones.
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#
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# See the mapping rules in table_name and the full example in link:files/README.html for more insight.
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#
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# == Creation
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#
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# Active Records accepts constructor parameters either in a hash or as a block. The hash method is especially useful when
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# you're receiving the data from somewhere else, like a HTTP request. It works like this:
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#
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# user = User.new(:name => "David", :occupation => "Code Artist")
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# user.name # => "David"
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#
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# You can also use block initialization:
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#
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# user = User.new do |u|
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# u.name = "David"
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# u.occupation = "Code Artist"
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# end
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#
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# And of course you can just create a bare object and specify the attributes after the fact:
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#
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# user = User.new
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# user.name = "David"
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# user.occupation = "Code Artist"
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#
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# == Conditions
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#
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# Conditions can either be specified as a string or an array representing the WHERE-part of an SQL statement.
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# The array form is to be used when the condition input is tainted and requires sanitization. The string form can
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# be used for statements that doesn't involve tainted data. Examples:
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#
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# User < ActiveRecord::Base
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# def self.authenticate_unsafely(user_name, password)
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# find(:first, :conditions => "user_name = '#{user_name}' AND password = '#{password}'")
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# end
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#
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# def self.authenticate_safely(user_name, password)
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# find(:first, :conditions => [ "user_name = ? AND password = ?", user_name, password ])
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# end
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# end
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#
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# The <tt>authenticate_unsafely</tt> method inserts the parameters directly into the query and is thus susceptible to SQL-injection
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# attacks if the <tt>user_name</tt> and +password+ parameters come directly from a HTTP request. The <tt>authenticate_safely</tt> method,
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# on the other hand, will sanitize the <tt>user_name</tt> and +password+ before inserting them in the query, which will ensure that
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# an attacker can't escape the query and fake the login (or worse).
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#
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# When using multiple parameters in the conditions, it can easily become hard to read exactly what the fourth or fifth
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# question mark is supposed to represent. In those cases, you can resort to named bind variables instead. That's done by replacing
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# the question marks with symbols and supplying a hash with values for the matching symbol keys:
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#
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# Company.find(:first, [
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# "id = :id AND name = :name AND division = :division AND created_at > :accounting_date",
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# { :id => 3, :name => "37signals", :division => "First", :accounting_date => '2005-01-01' }
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# ])
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#
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# == Overwriting default accessors
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#
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# All column values are automatically available through basic accessors on the Active Record object, but some times you
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# want to specialize this behavior. This can be done by either by overwriting the default accessors (using the same
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# name as the attribute) calling read_attribute(attr_name) and write_attribute(attr_name, value) to actually change things.
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# Example:
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#
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# class Song < ActiveRecord::Base
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# # Uses an integer of seconds to hold the length of the song
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#
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# def length=(minutes)
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# write_attribute(:length, minutes * 60)
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# end
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#
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# def length
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# read_attribute(:length) / 60
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# end
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# end
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#
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# You can alternatively use self[:attribute]=(value) and self[:attribute] instead of write_attribute(:attribute, vaule) and
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# read_attribute(:attribute) as a shorter form.
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#
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# == Accessing attributes before they have been type casted
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#
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# Some times you want to be able to read the raw attribute data without having the column-determined type cast run its course first.
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# That can be done by using the <attribute>_before_type_cast accessors that all attributes have. For example, if your Account model
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# has a balance attribute, you can call account.balance_before_type_cast or account.id_before_type_cast.
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#
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# This is especially useful in validation situations where the user might supply a string for an integer field and you want to display
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# the original string back in an error message. Accessing the attribute normally would type cast the string to 0, which isn't what you
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# want.
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#
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# == Dynamic attribute-based finders
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#
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# Dynamic attribute-based finders are a cleaner way of getting objects by simple queries without turning to SQL. They work by
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# appending the name of an attribute to <tt>find_by_</tt> or <tt>find_all_by_</tt>, so you get finders like Person.find_by_user_name,
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# Person.find_all_by_last_name, Payment.find_by_transaction_id. So instead of writing
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# <tt>Person.find(:first, ["user_name = ?", user_name])</tt>, you just do <tt>Person.find_by_user_name(user_name)</tt>.
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# And instead of writing <tt>Person.find(:all, ["last_name = ?", last_name])</tt>, you just do <tt>Person.find_all_by_last_name(last_name)</tt>.
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#
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# It's also possible to use multiple attributes in the same find by separating them with "_and_", so you get finders like
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# <tt>Person.find_by_user_name_and_password</tt> or even <tt>Payment.find_by_purchaser_and_state_and_country</tt>. So instead of writing
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# <tt>Person.find(:first, ["user_name = ? AND password = ?", user_name, password])</tt>, you just do
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# <tt>Person.find_by_user_name_and_password(user_name, password)</tt>.
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#
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# It's even possible to use all the additional parameters to find. For example, the full interface for Payment.find_all_by_amount
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# is actually Payment.find_all_by_amount(amount, options). And the full interface to Person.find_by_user_name is
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# actually Person.find_by_user_name(user_name, options). So you could call <tt>Payment.find_all_by_amount(50, :order => "created_on")</tt>.
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#
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# == Saving arrays, hashes, and other non-mappable objects in text columns
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#
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# Active Record can serialize any object in text columns using YAML. To do so, you must specify this with a call to the class method +serialize+.
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# This makes it possible to store arrays, hashes, and other non-mappeable objects without doing any additional work. Example:
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#
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# class User < ActiveRecord::Base
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# serialize :preferences
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# end
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#
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# user = User.create(:preferences) => { "background" => "black", "display" => large })
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# User.find(user.id).preferences # => { "background" => "black", "display" => large }
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#
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# You can also specify an class option as the second parameter that'll raise an exception if a serialized object is retrieved as a
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# descendent of a class not in the hierarchy. Example:
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#
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# class User < ActiveRecord::Base
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# serialize :preferences, Hash
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# end
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#
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# user = User.create(:preferences => %w( one two three ))
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# User.find(user.id).preferences # raises SerializationTypeMismatch
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#
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# == Single table inheritance
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#
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# Active Record allows inheritance by storing the name of the class in a column that by default is called "type" (can be changed
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# by overwriting <tt>Base.inheritance_column</tt>). This means that an inheritance looking like this:
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#
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# class Company < ActiveRecord::Base; end
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# class Firm < Company; end
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# class Client < Company; end
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# class PriorityClient < Client; end
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#
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# When you do Firm.create(:name => "37signals"), this record will be saved in the companies table with type = "Firm". You can then
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# fetch this row again using Company.find(:first, "name = '37signals'") and it will return a Firm object.
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#
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# If you don't have a type column defined in your table, single-table inheritance won't be triggered. In that case, it'll work just
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# like normal subclasses with no special magic for differentiating between them or reloading the right type with find.
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#
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# Note, all the attributes for all the cases are kept in the same table. Read more:
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# http://www.martinfowler.com/eaaCatalog/singleTableInheritance.html
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#
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# == Connection to multiple databases in different models
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#
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# Connections are usually created through ActiveRecord::Base.establish_connection and retrieved by ActiveRecord::Base.connection.
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# All classes inheriting from ActiveRecord::Base will use this connection. But you can also set a class-specific connection.
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# For example, if Course is a ActiveRecord::Base, but resides in a different database you can just say Course.establish_connection
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# and Course *and all its subclasses* will use this connection instead.
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#
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# This feature is implemented by keeping a connection pool in ActiveRecord::Base that is a Hash indexed by the class. If a connection is
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# requested, the retrieve_connection method will go up the class-hierarchy until a connection is found in the connection pool.
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#
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# == Exceptions
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#
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# * +ActiveRecordError+ -- generic error class and superclass of all other errors raised by Active Record
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# * +AdapterNotSpecified+ -- the configuration hash used in <tt>establish_connection</tt> didn't include a
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# <tt>:adapter</tt> key.
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# * +AdapterNotSpecified+ -- the <tt>:adapter</tt> key used in <tt>establish_connection</tt> specified an non-existent adapter
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# (or a bad spelling of an existing one).
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# * +AssociationTypeMismatch+ -- the object assigned to the association wasn't of the type specified in the association definition.
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# * +SerializationTypeMismatch+ -- the object serialized wasn't of the class specified as the second parameter.
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# * +ConnectionNotEstablished+ -- no connection has been established. Use <tt>establish_connection</tt> before querying.
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# * +RecordNotFound+ -- no record responded to the find* method.
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# Either the row with the given ID doesn't exist or the row didn't meet the additional restrictions.
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# * +StatementInvalid+ -- the database server rejected the SQL statement. The precise error is added in the message.
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# Either the record with the given ID doesn't exist or the record didn't meet the additional restrictions.
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# * +MultiparameterAssignmentErrors+ -- collection of errors that occurred during a mass assignment using the
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# +attributes=+ method. The +errors+ property of this exception contains an array of +AttributeAssignmentError+
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# objects that should be inspected to determine which attributes triggered the errors.
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# * +AttributeAssignmentError+ -- an error occurred while doing a mass assignment through the +attributes=+ method.
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# You can inspect the +attribute+ property of the exception object to determine which attribute triggered the error.
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# *Note*: The attributes listed are class-level attributes (accessible from both the class and instance level).
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# So it's possible to assign a logger to the class through Base.logger= which will then be used by all
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# instances in the current object space.
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class Base
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include ClassInheritableAttributes
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# Accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class, which is then passed
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# on to any new database connections made and which can be retrieved on both a class and instance level by calling +logger+.
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cattr_accessor :logger
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# Returns the connection currently associated with the class. This can
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# also be used to "borrow" the connection to do database work unrelated
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# to any of the specific Active Records.
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def self.connection
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retrieve_connection
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end
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# Returns the connection currently associated with the class. This can
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# also be used to "borrow" the connection to do database work that isn't
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# easily done without going straight to SQL.
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def connection
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self.class.connection
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end
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def self.inherited(child) #:nodoc:
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@@subclasses[self] ||= []
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@@subclasses[self] << child
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super
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end
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@@subclasses = {}
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cattr_accessor :configurations
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@@configurations = {}
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# Accessor for the prefix type that will be prepended to every primary key column name. The options are :table_name and
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# :table_name_with_underscore. If the first is specified, the Product class will look for "productid" instead of "id" as
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# the primary column. If the latter is specified, the Product class will look for "product_id" instead of "id". Remember
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# that this is a global setting for all Active Records.
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cattr_accessor :primary_key_prefix_type
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@@primary_key_prefix_type = nil
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# Accessor for the name of the prefix string to prepend to every table name. So if set to "basecamp_", all
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# table names will be named like "basecamp_projects", "basecamp_people", etc. This is a convenient way of creating a namespace
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# for tables in a shared database. By default, the prefix is the empty string.
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cattr_accessor :table_name_prefix
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@@table_name_prefix = ""
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# Works like +table_name_prefix+, but appends instead of prepends (set to "_basecamp" gives "projects_basecamp",
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# "people_basecamp"). By default, the suffix is the empty string.
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cattr_accessor :table_name_suffix
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@@table_name_suffix = ""
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# Indicate whether or not table names should be the pluralized versions of the corresponding class names.
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# If true, this the default table name for a +Product+ class will be +products+. If false, it would just be +product+.
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# See table_name for the full rules on table/class naming. This is true, by default.
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cattr_accessor :pluralize_table_names
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@@pluralize_table_names = true
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# Determines whether or not to use ANSI codes to colorize the logging statements committed by the connection adapter. These colors
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# makes it much easier to overview things during debugging (when used through a reader like +tail+ and on a black background), but
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# may complicate matters if you use software like syslog. This is true, by default.
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cattr_accessor :colorize_logging
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@@colorize_logging = true
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# Determines whether to use Time.local (using :local) or Time.utc (using :utc) when pulling dates and times from the database.
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# This is set to :local by default.
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cattr_accessor :default_timezone
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@@default_timezone = :local
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class << self # Class methods
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# Find operates with three different retreval approaches:
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#
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# * Find by id: This can either be a specific id (1), a list of ids (1, 5, 6), or an array of ids ([5, 6, 10]).
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# If no record can be found for all of the listed ids, then RecordNotFound will be raised.
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# * Find first: This will return the first record matched by the options used. These options can either be specific
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# conditions or merely an order. If no record can matched, nil is returned.
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# * Find all: This will return all the records matched by the options used. If no records are found, an empty array is returned.
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#
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# All approaches accepts an option hash as their last parameter. The options are:
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#
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# * <tt>:conditions</tt>: An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro.
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# * <tt>:order</tt>: An SQL fragment like "created_at DESC, name".
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# * <tt>:limit</tt>: An integer determining the limit on the number of rows that should be returned.
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# * <tt>:offset</tt>: An integer determining the offset from where the rows should be fetched. So at 5, it would skip the first 4 rows.
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# * <tt>:joins</tt>: An SQL fragment for additional joins like "LEFT JOIN comments ON comments.post_id = id". (Rarely needed).
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# * <tt>:include</tt>: Names associations that should be loaded alongside using LEFT OUTER JOINs. The symbols named refer
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# to already defined associations. See eager loading under Associations.
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#
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# Examples for find by id:
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# Person.find(1) # returns the object for ID = 1
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# Person.find(1, 2, 6) # returns an array for objects with IDs in (1, 2, 6)
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# Person.find([7, 17]) # returns an array for objects with IDs in (7, 17)
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# Person.find([1]) # returns an array for objects the object with ID = 1
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# Person.find(1, :conditions => "administrator = 1", :order => "created_on DESC")
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#
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# Examples for find first:
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# Person.find(:first) # returns the first object fetched by SELECT * FROM people
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# Person.find(:first, :conditions => [ "user_name = ?", user_name])
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# Person.find(:first, :order => "created_on DESC", :offset => 5)
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#
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# Examples for find all:
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# Person.find(:all) # returns an array of objects for all the rows fetched by SELECT * FROM people
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# Person.find(:all, :conditions => [ "category IN (?)", categories], :limit => 50)
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# Person.find(:all, :offset => 10, :limit => 10)
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# Person.find(:all, :include => [ :account, :friends ])
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def find(*args)
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options = extract_options_from_args!(args)
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case args.first
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when :first
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find(:all, options.merge({ :limit => 1 })).first
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when :all
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options[:include] ? find_with_associations(options) : find_by_sql(construct_finder_sql(options))
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else
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return args.first if args.first.kind_of?(Array) && args.first.empty?
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expects_array = args.first.kind_of?(Array)
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conditions = " AND #{sanitize_sql(options[:conditions])}" if options[:conditions]
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ids = args.flatten.compact.uniq
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case ids.size
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when 0
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raise RecordNotFound, "Couldn't find #{name} without an ID#{conditions}"
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when 1
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if result = find(:first, options.merge({ :conditions => "#{table_name}.#{primary_key} = #{sanitize(ids.first)}#{conditions}" }))
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return expects_array ? [ result ] : result
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else
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raise RecordNotFound, "Couldn't find #{name} with ID=#{ids.first}#{conditions}"
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end
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else
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# Find multiple ids
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ids_list = ids.map { |id| sanitize(id) }.join(',')
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result = find(:all, options.merge({ :conditions => "#{table_name}.#{primary_key} IN (#{ids_list})#{conditions}"}))
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if result.size == ids.size
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return result
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else
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raise RecordNotFound, "Couldn't find all #{name.pluralize} with IDs (#{ids_list})#{conditions}"
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end
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end
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end
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end
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# Works like find(:all), but requires a complete SQL string. Examples:
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# Post.find_by_sql "SELECT p.*, c.author FROM posts p, comments c WHERE p.id = c.post_id"
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# Post.find_by_sql ["SELECT * FROM posts WHERE author = ? AND created > ?", author_id, start_date]
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def find_by_sql(sql)
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connection.select_all(sanitize_sql(sql), "#{name} Load").collect! { |record| instantiate(record) }
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end
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# Returns true if the given +id+ represents the primary key of a record in the database, false otherwise.
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# Example:
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# Person.exists?(5)
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def exists?(id)
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!find(:first, :conditions => ["#{primary_key} = ?", id]).nil? rescue false
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end
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# Creates an object, instantly saves it as a record (if the validation permits it), and returns it. If the save
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# fail under validations, the unsaved object is still returned.
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def create(attributes = nil)
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if attributes.is_a?(Array)
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attributes.collect { |attr| create(attr) }
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else
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object = new(attributes)
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object.save
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object
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end
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end
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# Finds the record from the passed +id+, instantly saves it with the passed +attributes+ (if the validation permits it),
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# and returns it. If the save fail under validations, the unsaved object is still returned.
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def update(id, attributes)
|
|
if id.is_a?(Array)
|
|
idx = -1
|
|
id.collect { |id| idx += 1; update(id, attributes[idx]) }
|
|
else
|
|
object = find(id)
|
|
object.update_attributes(attributes)
|
|
object
|
|
end
|
|
end
|
|
|
|
# Deletes the record with the given +id+ without instantiating an object first. If an array of ids is provided, all of them
|
|
# are deleted.
|
|
def delete(id)
|
|
delete_all([ "#{primary_key} IN (?)", id ])
|
|
end
|
|
|
|
# Destroys the record with the given +id+ by instantiating the object and calling #destroy (all the callbacks are the triggered).
|
|
# If an array of ids is provided, all of them are destroyed.
|
|
def destroy(id)
|
|
id.is_a?(Array) ? id.each { |id| destroy(id) } : find(id).destroy
|
|
end
|
|
|
|
# Updates all records with the SET-part of an SQL update statement in +updates+ and returns an integer with the number of rows updates.
|
|
# A subset of the records can be selected by specifying +conditions+. Example:
|
|
# Billing.update_all "category = 'authorized', approved = 1", "author = 'David'"
|
|
def update_all(updates, conditions = nil)
|
|
sql = "UPDATE #{table_name} SET #{sanitize_sql(updates)} "
|
|
add_conditions!(sql, conditions)
|
|
connection.update(sql, "#{name} Update")
|
|
end
|
|
|
|
# Destroys the objects for all the records that matches the +condition+ by instantiating each object and calling
|
|
# the destroy method. Example:
|
|
# Person.destroy_all "last_login < '2004-04-04'"
|
|
def destroy_all(conditions = nil)
|
|
find(:all, :conditions => conditions).each { |object| object.destroy }
|
|
end
|
|
|
|
# Deletes all the records that matches the +condition+ without instantiating the objects first (and hence not
|
|
# calling the destroy method). Example:
|
|
# Post.destroy_all "person_id = 5 AND (category = 'Something' OR category = 'Else')"
|
|
def delete_all(conditions = nil)
|
|
sql = "DELETE FROM #{table_name} "
|
|
add_conditions!(sql, conditions)
|
|
connection.delete(sql, "#{name} Delete all")
|
|
end
|
|
|
|
# Returns the number of records that meets the +conditions+. Zero is returned if no records match. Example:
|
|
# Product.count "sales > 1"
|
|
def count(conditions = nil, joins = nil)
|
|
sql = "SELECT COUNT(*) FROM #{table_name} "
|
|
sql << " #{joins} " if joins
|
|
add_conditions!(sql, conditions)
|
|
count_by_sql(sql)
|
|
end
|
|
|
|
# Returns the result of an SQL statement that should only include a COUNT(*) in the SELECT part.
|
|
# Product.count "SELECT COUNT(*) FROM sales s, customers c WHERE s.customer_id = c.id"
|
|
def count_by_sql(sql)
|
|
sql = sanitize_conditions(sql)
|
|
rows = connection.select_one(sql, "#{name} Count")
|
|
|
|
if !rows.nil? and count = rows.values.first
|
|
count.to_i
|
|
else
|
|
0
|
|
end
|
|
end
|
|
|
|
# Increments the specified counter by one. So <tt>DiscussionBoard.increment_counter("post_count",
|
|
# discussion_board_id)</tt> would increment the "post_count" counter on the board responding to discussion_board_id.
|
|
# This is used for caching aggregate values, so that they doesn't need to be computed every time. Especially important
|
|
# for looping over a collection where each element require a number of aggregate values. Like the DiscussionBoard
|
|
# that needs to list both the number of posts and comments.
|
|
def increment_counter(counter_name, id)
|
|
update_all "#{counter_name} = #{counter_name} + 1", "#{primary_key} = #{quote(id)}"
|
|
end
|
|
|
|
# Works like increment_counter, but decrements instead.
|
|
def decrement_counter(counter_name, id)
|
|
update_all "#{counter_name} = #{counter_name} - 1", "#{primary_key} = #{quote(id)}"
|
|
end
|
|
|
|
# Attributes named in this macro are protected from mass-assignment, such as <tt>new(attributes)</tt> and
|
|
# <tt>attributes=(attributes)</tt>. Their assignment will simply be ignored. Instead, you can use the direct writer
|
|
# methods to do assignment. This is meant to protect sensitive attributes to be overwritten by URL/form hackers. Example:
|
|
#
|
|
# class Customer < ActiveRecord::Base
|
|
# attr_protected :credit_rating
|
|
# end
|
|
#
|
|
# customer = Customer.new("name" => David, "credit_rating" => "Excellent")
|
|
# customer.credit_rating # => nil
|
|
# customer.attributes = { "description" => "Jolly fellow", "credit_rating" => "Superb" }
|
|
# customer.credit_rating # => nil
|
|
#
|
|
# customer.credit_rating = "Average"
|
|
# customer.credit_rating # => "Average"
|
|
def attr_protected(*attributes)
|
|
write_inheritable_array("attr_protected", attributes)
|
|
end
|
|
|
|
# Returns an array of all the attributes that have been protected from mass-assignment.
|
|
def protected_attributes # :nodoc:
|
|
read_inheritable_attribute("attr_protected")
|
|
end
|
|
|
|
# If this macro is used, only those attributed named in it will be accessible for mass-assignment, such as
|
|
# <tt>new(attributes)</tt> and <tt>attributes=(attributes)</tt>. This is the more conservative choice for mass-assignment
|
|
# protection. If you'd rather start from an all-open default and restrict attributes as needed, have a look at
|
|
# attr_protected.
|
|
def attr_accessible(*attributes)
|
|
write_inheritable_array("attr_accessible", attributes)
|
|
end
|
|
|
|
# Returns an array of all the attributes that have been made accessible to mass-assignment.
|
|
def accessible_attributes # :nodoc:
|
|
read_inheritable_attribute("attr_accessible")
|
|
end
|
|
|
|
# Specifies that the attribute by the name of +attr_name+ should be serialized before saving to the database and unserialized
|
|
# after loading from the database. The serialization is done through YAML. If +class_name+ is specified, the serialized
|
|
# object must be of that class on retrieval or +SerializationTypeMismatch+ will be raised.
|
|
def serialize(attr_name, class_name = Object)
|
|
serialized_attributes[attr_name.to_s] = class_name
|
|
end
|
|
|
|
# Returns a hash of all the attributes that have been specified for serialization as keys and their class restriction as values.
|
|
def serialized_attributes
|
|
read_inheritable_attribute("attr_serialized") or write_inheritable_attribute("attr_serialized", {})
|
|
end
|
|
|
|
# Guesses the table name (in forced lower-case) based on the name of the class in the inheritance hierarchy descending
|
|
# directly from ActiveRecord. So if the hierarchy looks like: Reply < Message < ActiveRecord, then Message is used
|
|
# to guess the table name from even when called on Reply. The rules used to do the guess are handled by the Inflector class
|
|
# in Active Support, which knows almost all common English inflections (report a bug if your inflection isn't covered).
|
|
#
|
|
# Additionally, the class-level table_name_prefix is prepended to the table_name and the table_name_suffix is appended.
|
|
# So if you have "myapp_" as a prefix, the table name guess for an Account class becomes "myapp_accounts".
|
|
#
|
|
# You can also overwrite this class method to allow for unguessable links, such as a Mouse class with a link to a
|
|
# "mice" table. Example:
|
|
#
|
|
# class Mouse < ActiveRecord::Base
|
|
# set_table_name "mice"
|
|
# end
|
|
def table_name
|
|
"#{table_name_prefix}#{undecorated_table_name(class_name_of_active_record_descendant(self))}#{table_name_suffix}"
|
|
end
|
|
|
|
# Defines the primary key field -- can be overridden in subclasses. Overwriting will negate any effect of the
|
|
# primary_key_prefix_type setting, though.
|
|
def primary_key
|
|
case primary_key_prefix_type
|
|
when :table_name
|
|
Inflector.foreign_key(class_name_of_active_record_descendant(self), false)
|
|
when :table_name_with_underscore
|
|
Inflector.foreign_key(class_name_of_active_record_descendant(self))
|
|
else
|
|
"id"
|
|
end
|
|
end
|
|
|
|
# Defines the column name for use with single table inheritance -- can be overridden in subclasses.
|
|
def inheritance_column
|
|
"type"
|
|
end
|
|
|
|
# Sets the table name to use to the given value, or (if the value
|
|
# is nil or false) to the value returned by the given block.
|
|
#
|
|
# Example:
|
|
#
|
|
# class Project < ActiveRecord::Base
|
|
# set_table_name "project"
|
|
# end
|
|
def set_table_name( value=nil, &block )
|
|
define_attr_method :table_name, value, &block
|
|
end
|
|
alias :table_name= :set_table_name
|
|
|
|
# Sets the name of the primary key column to use to the given value,
|
|
# or (if the value is nil or false) to the value returned by the given
|
|
# block.
|
|
#
|
|
# Example:
|
|
#
|
|
# class Project < ActiveRecord::Base
|
|
# set_primary_key "sysid"
|
|
# end
|
|
def set_primary_key( value=nil, &block )
|
|
define_attr_method :primary_key, value, &block
|
|
end
|
|
alias :primary_key= :set_primary_key
|
|
|
|
# Sets the name of the inheritance column to use to the given value,
|
|
# or (if the value # is nil or false) to the value returned by the
|
|
# given block.
|
|
#
|
|
# Example:
|
|
#
|
|
# class Project < ActiveRecord::Base
|
|
# set_inheritance_column do
|
|
# original_inheritance_column + "_id"
|
|
# end
|
|
# end
|
|
def set_inheritance_column( value=nil, &block )
|
|
define_attr_method :inheritance_column, value, &block
|
|
end
|
|
alias :inheritance_column= :set_inheritance_column
|
|
|
|
# Turns the +table_name+ back into a class name following the reverse rules of +table_name+.
|
|
def class_name(table_name = table_name) # :nodoc:
|
|
# remove any prefix and/or suffix from the table name
|
|
class_name = table_name[table_name_prefix.length..-(table_name_suffix.length + 1)].camelize
|
|
class_name = class_name.singularize if pluralize_table_names
|
|
class_name
|
|
end
|
|
|
|
# Returns an array of column objects for the table associated with this class.
|
|
def columns
|
|
@columns ||= connection.columns(table_name, "#{name} Columns")
|
|
end
|
|
|
|
# Returns an array of column objects for the table associated with this class.
|
|
def columns_hash
|
|
@columns_hash ||= columns.inject({}) { |hash, column| hash[column.name] = column; hash }
|
|
end
|
|
|
|
def column_names
|
|
@column_names ||= columns.map { |column| column.name }
|
|
end
|
|
|
|
# Returns an array of columns objects where the primary id, all columns ending in "_id" or "_count",
|
|
# and columns used for single table inheritance has been removed.
|
|
def content_columns
|
|
@content_columns ||= columns.reject { |c| c.name == primary_key || c.name =~ /(_id|_count)$/ || c.name == inheritance_column }
|
|
end
|
|
|
|
# Returns a hash of all the methods added to query each of the columns in the table with the name of the method as the key
|
|
# and true as the value. This makes it possible to do O(1) lookups in respond_to? to check if a given method for attribute
|
|
# is available.
|
|
def column_methods_hash
|
|
@dynamic_methods_hash ||= column_names.inject(Hash.new(false)) do |methods, attr|
|
|
methods[attr.to_sym] = true
|
|
methods["#{attr}=".to_sym] = true
|
|
methods["#{attr}?".to_sym] = true
|
|
methods["#{attr}_before_type_cast".to_sym] = true
|
|
methods
|
|
end
|
|
end
|
|
|
|
# Resets all the cached information about columns, which will cause they to be reloaded on the next request.
|
|
def reset_column_information
|
|
@column_names = @columns = @columns_hash = @content_columns = @dynamic_methods_hash = nil
|
|
end
|
|
|
|
def reset_column_information_and_inheritable_attributes_for_all_subclasses#:nodoc:
|
|
subclasses.each { |klass| klass.reset_inheritable_attributes; klass.reset_column_information }
|
|
end
|
|
|
|
# Transforms attribute key names into a more humane format, such as "First name" instead of "first_name". Example:
|
|
# Person.human_attribute_name("first_name") # => "First name"
|
|
# Deprecated in favor of just calling "first_name".humanize
|
|
def human_attribute_name(attribute_key_name) #:nodoc:
|
|
attribute_key_name.humanize
|
|
end
|
|
|
|
def descends_from_active_record? # :nodoc:
|
|
superclass == Base || !columns_hash.include?(inheritance_column)
|
|
end
|
|
|
|
def quote(object) #:nodoc:
|
|
connection.quote(object)
|
|
end
|
|
|
|
# Used to sanitize objects before they're used in an SELECT SQL-statement. Delegates to <tt>connection.quote</tt>.
|
|
def sanitize(object) #:nodoc:
|
|
connection.quote(object)
|
|
end
|
|
|
|
# Log and benchmark multiple statements in a single block.
|
|
# Usage (hides all the SQL calls for the individual actions and calculates total runtime for them all):
|
|
#
|
|
# Project.benchmark("Creating project") do
|
|
# project = Project.create("name" => "stuff")
|
|
# project.create_manager("name" => "David")
|
|
# project.milestones << Milestone.find(:all)
|
|
# end
|
|
def benchmark(title)
|
|
result = nil
|
|
seconds = Benchmark.realtime { result = silence { yield } }
|
|
logger.info "#{title} (#{sprintf("%f", seconds)})" if logger
|
|
return result
|
|
end
|
|
|
|
# Silences the logger for the duration of the block.
|
|
def silence
|
|
old_logger_level, logger.level = logger.level, Logger::ERROR if logger
|
|
yield
|
|
ensure
|
|
logger.level = old_logger_level if logger
|
|
end
|
|
|
|
# Overwrite the default class equality method to provide support for association proxies.
|
|
def ===(object)
|
|
object.is_a?(self)
|
|
end
|
|
|
|
private
|
|
# Finder methods must instantiate through this method to work with the single-table inheritance model
|
|
# that makes it possible to create objects of different types from the same table.
|
|
def instantiate(record)
|
|
subclass_name = record[inheritance_column]
|
|
require_association_class(subclass_name)
|
|
|
|
object = if subclass_name.blank?
|
|
allocate
|
|
else
|
|
begin
|
|
compute_type(subclass_name).allocate
|
|
rescue NameError
|
|
raise SubclassNotFound,
|
|
"The single-table inheritance mechanism failed to locate the subclass: '#{record[inheritance_column]}'. " +
|
|
"This error is raised because the column '#{inheritance_column}' is reserved for storing the class in case of inheritance. " +
|
|
"Please rename this column if you didn't intend it to be used for storing the inheritance class " +
|
|
"or overwrite #{self.to_s}.inheritance_column to use another column for that information."
|
|
end
|
|
end
|
|
|
|
object.instance_variable_set("@attributes", record)
|
|
object
|
|
end
|
|
|
|
# Returns the name of the type of the record using the current module as a prefix. So descendents of
|
|
# MyApp::Business::Account would be appear as "MyApp::Business::AccountSubclass".
|
|
def type_name_with_module(type_name)
|
|
self.name =~ /::/ ? self.name.scan(/(.*)::/).first.first + "::" + type_name : type_name
|
|
end
|
|
|
|
def construct_finder_sql(options)
|
|
sql = "SELECT * FROM #{table_name} "
|
|
sql << " #{options[:joins]} " if options[:joins]
|
|
add_conditions!(sql, options[:conditions])
|
|
sql << "ORDER BY #{options[:order]} " if options[:order]
|
|
add_limit!(sql, options)
|
|
sql
|
|
end
|
|
|
|
def add_limit!(sql, options)
|
|
connection.add_limit_offset!(sql, options)
|
|
end
|
|
|
|
# Adds a sanitized version of +conditions+ to the +sql+ string. Note that it's the passed +sql+ string is changed.
|
|
def add_conditions!(sql, conditions)
|
|
sql << "WHERE #{sanitize_sql(conditions)} " unless conditions.nil?
|
|
sql << (conditions.nil? ? "WHERE " : " AND ") + type_condition unless descends_from_active_record?
|
|
end
|
|
|
|
def type_condition
|
|
type_condition = subclasses.inject("#{table_name}.#{inheritance_column} = '#{name.demodulize}' ") do |condition, subclass|
|
|
condition << "OR #{table_name}.#{inheritance_column} = '#{subclass.name.demodulize}' "
|
|
end
|
|
|
|
" (#{type_condition}) "
|
|
end
|
|
|
|
# Guesses the table name, but does not decorate it with prefix and suffix information.
|
|
def undecorated_table_name(class_name = class_name_of_active_record_descendant(self))
|
|
table_name = Inflector.underscore(Inflector.demodulize(class_name))
|
|
table_name = Inflector.pluralize(table_name) if pluralize_table_names
|
|
table_name
|
|
end
|
|
|
|
# Enables dynamic finders like find_by_user_name(user_name) and find_by_user_name_and_password(user_name, password) that are turned into
|
|
# find(:first, :conditions => ["user_name = ?", user_name]) and find(:first, :conditions => ["user_name = ? AND password = ?", user_name, password])
|
|
# respectively. Also works for find(:all), but using find_all_by_amount(50) that are turned into find(:all, :conditions => ["amount = ?", 50]).
|
|
#
|
|
# It's even possible to use all the additional parameters to find. For example, the full interface for find_all_by_amount
|
|
# is actually find_all_by_amount(amount, options).
|
|
def method_missing(method_id, *arguments)
|
|
method_name = method_id.id2name
|
|
|
|
if md = /find_(all_by|by)_([_a-zA-Z]\w*)/.match(method_id.to_s)
|
|
finder = md.captures.first == 'all_by' ? :all : :first
|
|
attributes = md.captures.last.split('_and_')
|
|
attributes.each { |attr_name| super unless column_methods_hash.include?(attr_name.to_sym) }
|
|
|
|
attr_index = -1
|
|
conditions = attributes.collect { |attr_name| attr_index += 1; "#{attr_name} #{attribute_condition(arguments[attr_index])} " }.join(" AND ")
|
|
|
|
if arguments[attributes.length].is_a?(Hash)
|
|
find(finder, { :conditions => [conditions, *arguments[0...attributes.length]] }.update(arguments[attributes.length]))
|
|
else
|
|
# deprecated API
|
|
send("find_#{finder}", [conditions, *arguments[0...attributes.length]], *arguments[attributes.length..-1])
|
|
end
|
|
else
|
|
super
|
|
end
|
|
end
|
|
|
|
def attribute_condition(argument)
|
|
case argument
|
|
when nil then "IS ?"
|
|
when Array then "IN (?)"
|
|
else "= ?"
|
|
end
|
|
end
|
|
|
|
# Defines an "attribute" method (like #inheritance_column or
|
|
# #table_name). A new (class) method will be created with the
|
|
# given name. If a value is specified, the new method will
|
|
# return that value (as a string). Otherwise, the given block
|
|
# will be used to compute the value of the method.
|
|
#
|
|
# The original method will be aliased, with the new name being
|
|
# prefixed with "original_". This allows the new method to
|
|
# access the original value.
|
|
#
|
|
# Example:
|
|
#
|
|
# class A < ActiveRecord::Base
|
|
# define_attr_method :primary_key, "sysid"
|
|
# define_attr_method( :inheritance_column ) do
|
|
# original_inheritance_column + "_id"
|
|
# end
|
|
# end
|
|
def define_attr_method(name, value=nil, &block)
|
|
sing = class << self; self; end
|
|
block = proc { value.to_s } if value
|
|
sing.send( :alias_method, "original_#{name}", name )
|
|
sing.send( :define_method, name, &block )
|
|
end
|
|
|
|
protected
|
|
def subclasses
|
|
@@subclasses[self] ||= []
|
|
@@subclasses[self] + extra = @@subclasses[self].inject([]) {|list, subclass| list + subclass.subclasses }
|
|
end
|
|
|
|
# Returns the class type of the record using the current module as a prefix. So descendents of
|
|
# MyApp::Business::Account would be appear as MyApp::Business::AccountSubclass.
|
|
def compute_type(type_name)
|
|
type_name_with_module(type_name).split("::").inject(Object) do |final_type, part|
|
|
final_type = final_type.const_get(part)
|
|
end
|
|
end
|
|
|
|
# Returns the name of the class descending directly from ActiveRecord in the inheritance hierarchy.
|
|
def class_name_of_active_record_descendant(klass)
|
|
if klass.superclass == Base
|
|
klass.name
|
|
elsif klass.superclass.nil?
|
|
raise ActiveRecordError, "#{name} doesn't belong in a hierarchy descending from ActiveRecord"
|
|
else
|
|
class_name_of_active_record_descendant(klass.superclass)
|
|
end
|
|
end
|
|
|
|
# Accepts an array or string. The string is returned untouched, but the array has each value
|
|
# sanitized and interpolated into the sql statement.
|
|
# ["name='%s' and group_id='%s'", "foo'bar", 4] returns "name='foo''bar' and group_id='4'"
|
|
def sanitize_sql(ary)
|
|
return ary unless ary.is_a?(Array)
|
|
|
|
statement, *values = ary
|
|
if values.first.is_a?(Hash) and statement =~ /:\w+/
|
|
replace_named_bind_variables(statement, values.first)
|
|
elsif statement.include?('?')
|
|
replace_bind_variables(statement, values)
|
|
else
|
|
statement % values.collect { |value| connection.quote_string(value.to_s) }
|
|
end
|
|
end
|
|
|
|
alias_method :sanitize_conditions, :sanitize_sql
|
|
|
|
def replace_bind_variables(statement, values)
|
|
raise_if_bind_arity_mismatch(statement, statement.count('?'), values.size)
|
|
bound = values.dup
|
|
statement.gsub('?') { quote_bound_value(bound.shift) }
|
|
end
|
|
|
|
def replace_named_bind_variables(statement, bind_vars)
|
|
raise_if_bind_arity_mismatch(statement, statement.scan(/:(\w+)/).uniq.size, bind_vars.size)
|
|
statement.gsub(/:(\w+)/) do
|
|
match = $1.to_sym
|
|
if bind_vars.include?(match)
|
|
quote_bound_value(bind_vars[match])
|
|
else
|
|
raise PreparedStatementInvalid, "missing value for :#{match} in #{statement}"
|
|
end
|
|
end
|
|
end
|
|
|
|
def quote_bound_value(value)
|
|
if (value.respond_to?(:map) && !value.is_a?(String))
|
|
value.map { |v| connection.quote(v) }.join(',')
|
|
else
|
|
connection.quote(value)
|
|
end
|
|
end
|
|
|
|
def raise_if_bind_arity_mismatch(statement, expected, provided)
|
|
unless expected == provided
|
|
raise PreparedStatementInvalid, "wrong number of bind variables (#{provided} for #{expected}) in: #{statement}"
|
|
end
|
|
end
|
|
|
|
def extract_options_from_args!(args)
|
|
if args.last.is_a?(Hash) then args.pop else {} end
|
|
end
|
|
|
|
def encode_quoted_value(value)
|
|
quoted_value = connection.quote(value)
|
|
quoted_value = "'#{quoted_value[1..-2].gsub(/\'/, "\\\\'")}'" if quoted_value.include?("\\\'")
|
|
quoted_value
|
|
end
|
|
end
|
|
|
|
public
|
|
# New objects can be instantiated as either empty (pass no construction parameter) or pre-set with
|
|
# attributes but not yet saved (pass a hash with key names matching the associated table column names).
|
|
# In both instances, valid attribute keys are determined by the column names of the associated table --
|
|
# hence you can't have attributes that aren't part of the table columns.
|
|
def initialize(attributes = nil)
|
|
@attributes = attributes_from_column_definition
|
|
@new_record = true
|
|
ensure_proper_type
|
|
self.attributes = attributes unless attributes.nil?
|
|
yield self if block_given?
|
|
end
|
|
|
|
# Every Active Record class must use "id" as their primary ID. This getter overwrites the native
|
|
# id method, which isn't being used in this context.
|
|
def id
|
|
read_attribute(self.class.primary_key)
|
|
end
|
|
|
|
# Enables Active Record objects to be used as URL parameters in Action Pack automatically.
|
|
alias_method :to_param, :id
|
|
|
|
def id_before_type_cast #:nodoc:
|
|
read_attribute_before_type_cast(self.class.primary_key)
|
|
end
|
|
|
|
def quoted_id #:nodoc:
|
|
quote(id, column_for_attribute(self.class.primary_key))
|
|
end
|
|
|
|
# Sets the primary ID.
|
|
def id=(value)
|
|
write_attribute(self.class.primary_key, value)
|
|
end
|
|
|
|
# Returns true if this object hasn't been saved yet -- that is, a record for the object doesn't exist yet.
|
|
def new_record?
|
|
@new_record
|
|
end
|
|
|
|
# * No record exists: Creates a new record with values matching those of the object attributes.
|
|
# * A record does exist: Updates the record with values matching those of the object attributes.
|
|
def save
|
|
create_or_update
|
|
end
|
|
|
|
# Deletes the record in the database and freezes this instance to reflect that no changes should
|
|
# be made (since they can't be persisted).
|
|
def destroy
|
|
unless new_record?
|
|
connection.delete <<-end_sql, "#{self.class.name} Destroy"
|
|
DELETE FROM #{self.class.table_name}
|
|
WHERE #{self.class.primary_key} = #{quoted_id}
|
|
end_sql
|
|
end
|
|
|
|
freeze
|
|
end
|
|
|
|
# Returns a clone of the record that hasn't been assigned an id yet and is treated as a new record.
|
|
def clone
|
|
attrs = self.attributes_before_type_cast
|
|
attrs.delete(self.class.primary_key)
|
|
self.class.new do |record|
|
|
record.send :instance_variable_set, '@attributes', attrs
|
|
end
|
|
end
|
|
|
|
# Updates a single attribute and saves the record. This is especially useful for boolean flags on existing records.
|
|
# Note: This method is overwritten by the Validation module that'll make sure that updates made with this method
|
|
# doesn't get subjected to validation checks. Hence, attributes can be updated even if the full object isn't valid.
|
|
def update_attribute(name, value)
|
|
self[name] = value
|
|
save
|
|
end
|
|
|
|
# Updates all the attributes in from the passed hash and saves the record. If the object is invalid, the saving will
|
|
# fail and false will be returned.
|
|
def update_attributes(attributes)
|
|
self.attributes = attributes
|
|
save
|
|
end
|
|
|
|
# Initializes the +attribute+ to zero if nil and adds one. Only makes sense for number-based attributes. Returns self.
|
|
def increment(attribute)
|
|
self[attribute] ||= 0
|
|
self[attribute] += 1
|
|
self
|
|
end
|
|
|
|
# Increments the +attribute+ and saves the record.
|
|
def increment!(attribute)
|
|
increment(attribute).update_attribute(attribute, self[attribute])
|
|
end
|
|
|
|
# Initializes the +attribute+ to zero if nil and subtracts one. Only makes sense for number-based attributes. Returns self.
|
|
def decrement(attribute)
|
|
self[attribute] ||= 0
|
|
self[attribute] -= 1
|
|
self
|
|
end
|
|
|
|
# Decrements the +attribute+ and saves the record.
|
|
def decrement!(attribute)
|
|
decrement(attribute).update_attribute(attribute, self[attribute])
|
|
end
|
|
|
|
# Turns an +attribute+ that's currently true into false and vice versa. Returns self.
|
|
def toggle(attribute)
|
|
self[attribute] = quote(!send("#{attribute}?", column_for_attribute(attribute)))
|
|
self
|
|
end
|
|
|
|
# Toggles the +attribute+ and saves the record.
|
|
def toggle!(attribute)
|
|
toggle(attribute).update_attribute(attribute, self[attribute])
|
|
end
|
|
|
|
# Reloads the attributes of this object from the database.
|
|
def reload
|
|
clear_association_cache
|
|
@attributes.update(self.class.find(self.id).instance_variable_get('@attributes'))
|
|
self
|
|
end
|
|
|
|
# Returns the value of attribute identified by <tt>attr_name</tt> after it has been type cast (for example,
|
|
# "2004-12-12" in a data column is cast to a date object, like Date.new(2004, 12, 12)).
|
|
# (Alias for the protected read_attribute method).
|
|
def [](attr_name)
|
|
read_attribute(attr_name.to_s)
|
|
end
|
|
|
|
# Updates the attribute identified by <tt>attr_name</tt> with the specified +value+.
|
|
# (Alias for the protected write_attribute method).
|
|
def []=(attr_name, value)
|
|
write_attribute(attr_name.to_s, value)
|
|
end
|
|
|
|
# Allows you to set all the attributes at once by passing in a hash with keys
|
|
# matching the attribute names (which again matches the column names). Sensitive attributes can be protected
|
|
# from this form of mass-assignment by using the +attr_protected+ macro. Or you can alternatively
|
|
# specify which attributes *can* be accessed in with the +attr_accessible+ macro. Then all the
|
|
# attributes not included in that won't be allowed to be mass-assigned.
|
|
def attributes=(attributes)
|
|
return if attributes.nil?
|
|
attributes.stringify_keys!
|
|
|
|
multi_parameter_attributes = []
|
|
remove_attributes_protected_from_mass_assignment(attributes).each do |k, v|
|
|
k.include?("(") ? multi_parameter_attributes << [ k, v ] : send(k + "=", v)
|
|
end
|
|
assign_multiparameter_attributes(multi_parameter_attributes)
|
|
end
|
|
|
|
# Returns a hash of all the attributes with their names as keys and clones of their objects as values.
|
|
def attributes
|
|
clone_attributes :read_attribute
|
|
end
|
|
|
|
# Returns a hash of cloned attributes before typecasting and deserialization.
|
|
def attributes_before_type_cast
|
|
clone_attributes :read_attribute_before_type_cast
|
|
end
|
|
|
|
# Returns true if the specified +attribute+ has been set by the user or by a database load and is neither
|
|
# nil nor empty? (the latter only applies to objects that responds to empty?, most notably Strings).
|
|
def attribute_present?(attribute)
|
|
value = read_attribute(attribute)
|
|
!value.blank? or value == 0
|
|
end
|
|
|
|
# Returns an array of names for the attributes available on this object sorted alphabetically.
|
|
def attribute_names
|
|
@attributes.keys.sort
|
|
end
|
|
|
|
# Returns the column object for the named attribute.
|
|
def column_for_attribute(name)
|
|
self.class.columns_hash[name.to_s]
|
|
end
|
|
|
|
# Returns true if the +comparison_object+ is the same object, or is of the same type and has the same id.
|
|
def ==(comparison_object)
|
|
comparison_object.equal?(self) or (comparison_object.instance_of?(self.class) and comparison_object.id == id)
|
|
end
|
|
|
|
# Delegates to ==
|
|
def eql?(comparison_object)
|
|
self == (comparison_object)
|
|
end
|
|
|
|
# Delegates to id in order to allow two records of the same type and id to work with something like:
|
|
# [ Person.find(1), Person.find(2), Person.find(3) ] & [ Person.find(1), Person.find(4) ] # => [ Person.find(1) ]
|
|
def hash
|
|
id.hash
|
|
end
|
|
|
|
# For checking respond_to? without searching the attributes (which is faster).
|
|
alias_method :respond_to_without_attributes?, :respond_to?
|
|
|
|
# A Person object with a name attribute can ask person.respond_to?("name"), person.respond_to?("name="), and
|
|
# person.respond_to?("name?") which will all return true.
|
|
def respond_to?(method, include_priv = false)
|
|
self.class.column_methods_hash[method.to_sym] || respond_to_without_attributes?(method, include_priv)
|
|
end
|
|
|
|
# Just freeze the attributes hash, such that associations are still accessible even on destroyed records.
|
|
def freeze
|
|
@attributes.freeze
|
|
end
|
|
|
|
def frozen?
|
|
@attributes.frozen?
|
|
end
|
|
|
|
private
|
|
def create_or_update
|
|
if new_record? then create else update end
|
|
true
|
|
end
|
|
|
|
# Updates the associated record with values matching those of the instant attributes.
|
|
def update
|
|
connection.update(
|
|
"UPDATE #{self.class.table_name} " +
|
|
"SET #{quoted_comma_pair_list(connection, attributes_with_quotes(false))} " +
|
|
"WHERE #{self.class.primary_key} = #{quote(id)}",
|
|
"#{self.class.name} Update"
|
|
)
|
|
end
|
|
|
|
# Creates a new record with values matching those of the instant attributes.
|
|
def create
|
|
self.id = connection.insert(
|
|
"INSERT INTO #{self.class.table_name} " +
|
|
"(#{quoted_column_names.join(', ')}) " +
|
|
"VALUES(#{attributes_with_quotes.values.join(', ')})",
|
|
"#{self.class.name} Create",
|
|
self.class.primary_key, self.id
|
|
)
|
|
|
|
@new_record = false
|
|
end
|
|
|
|
# Sets the attribute used for single table inheritance to this class name if this is not the ActiveRecord descendant.
|
|
# Considering the hierarchy Reply < Message < ActiveRecord, this makes it possible to do Reply.new without having to
|
|
# set Reply[Reply.inheritance_column] = "Reply" yourself. No such attribute would be set for objects of the
|
|
# Message class in that example.
|
|
def ensure_proper_type
|
|
unless self.class.descends_from_active_record?
|
|
write_attribute(self.class.inheritance_column, Inflector.demodulize(self.class.name))
|
|
end
|
|
end
|
|
|
|
# Allows access to the object attributes, which are held in the @attributes hash, as were
|
|
# they first-class methods. So a Person class with a name attribute can use Person#name and
|
|
# Person#name= and never directly use the attributes hash -- except for multiple assigns with
|
|
# ActiveRecord#attributes=. A Milestone class can also ask Milestone#completed? to test that
|
|
# the completed attribute is not nil or 0.
|
|
#
|
|
# It's also possible to instantiate related objects, so a Client class belonging to the clients
|
|
# table with a master_id foreign key can instantiate master through Client#master.
|
|
def method_missing(method_id, *args, &block)
|
|
method_name = method_id.to_s
|
|
if @attributes.include?(method_name)
|
|
read_attribute(method_name)
|
|
elsif md = /(=|\?|_before_type_cast)$/.match(method_name)
|
|
attribute_name, method_type = md.pre_match, md.to_s
|
|
if @attributes.include?(attribute_name)
|
|
case method_type
|
|
when '='
|
|
write_attribute(attribute_name, args.first)
|
|
when '?'
|
|
query_attribute(attribute_name)
|
|
when '_before_type_cast'
|
|
read_attribute_before_type_cast(attribute_name)
|
|
end
|
|
else
|
|
super
|
|
end
|
|
else
|
|
super
|
|
end
|
|
end
|
|
|
|
# Returns the value of attribute identified by <tt>attr_name</tt> after it has been type cast (for example,
|
|
# "2004-12-12" in a data column is cast to a date object, like Date.new(2004, 12, 12)).
|
|
def read_attribute(attr_name)
|
|
if !(value = @attributes[attr_name]).nil?
|
|
if column = column_for_attribute(attr_name)
|
|
if unserializable_attribute?(attr_name, column)
|
|
unserialize_attribute(attr_name)
|
|
else
|
|
column.type_cast(value)
|
|
end
|
|
else
|
|
value
|
|
end
|
|
else
|
|
nil
|
|
end
|
|
end
|
|
|
|
def read_attribute_before_type_cast(attr_name)
|
|
@attributes[attr_name]
|
|
end
|
|
|
|
# Returns true if the attribute is of a text column and marked for serialization.
|
|
def unserializable_attribute?(attr_name, column)
|
|
if value = @attributes[attr_name]
|
|
[:text, :string].include?(column.send(:type)) && value.is_a?(String) && self.class.serialized_attributes[attr_name]
|
|
end
|
|
end
|
|
|
|
# Returns the unserialized object of the attribute.
|
|
def unserialize_attribute(attr_name)
|
|
unserialized_object = object_from_yaml(@attributes[attr_name])
|
|
|
|
if unserialized_object.is_a?(self.class.serialized_attributes[attr_name])
|
|
@attributes[attr_name] = unserialized_object
|
|
else
|
|
raise SerializationTypeMismatch,
|
|
"#{attr_name} was supposed to be a #{self.class.serialized_attributes[attr_name]}, but was a #{unserialized_object.class.to_s}"
|
|
end
|
|
end
|
|
|
|
# Updates the attribute identified by <tt>attr_name</tt> with the specified +value+. Empty strings for fixnum and float
|
|
# columns are turned into nil.
|
|
def write_attribute(attr_name, value)
|
|
@attributes[attr_name.to_s] = empty_string_for_number_column?(attr_name.to_s, value) ? nil : value
|
|
end
|
|
|
|
def empty_string_for_number_column?(attr_name, value)
|
|
column = column_for_attribute(attr_name)
|
|
column && (column.klass == Fixnum || column.klass == Float) && value == ""
|
|
end
|
|
|
|
def query_attribute(attr_name)
|
|
attribute = @attributes[attr_name]
|
|
if attribute.kind_of?(Fixnum) && attribute == 0
|
|
false
|
|
elsif attribute.kind_of?(String) && attribute == "0"
|
|
false
|
|
elsif attribute.kind_of?(String) && attribute.empty?
|
|
false
|
|
elsif attribute.nil?
|
|
false
|
|
elsif attribute == false
|
|
false
|
|
elsif attribute == "f"
|
|
false
|
|
elsif attribute == "false"
|
|
false
|
|
else
|
|
true
|
|
end
|
|
end
|
|
|
|
def remove_attributes_protected_from_mass_assignment(attributes)
|
|
if self.class.accessible_attributes.nil? && self.class.protected_attributes.nil?
|
|
attributes.reject { |key, value| attributes_protected_by_default.include?(key.gsub(/\(.+/, "")) }
|
|
elsif self.class.protected_attributes.nil?
|
|
attributes.reject { |key, value| !self.class.accessible_attributes.include?(key.gsub(/\(.+/, "").intern) || attributes_protected_by_default.include?(key.gsub(/\(.+/, "")) }
|
|
elsif self.class.accessible_attributes.nil?
|
|
attributes.reject { |key, value| self.class.protected_attributes.include?(key.gsub(/\(.+/,"").intern) || attributes_protected_by_default.include?(key.gsub(/\(.+/, "")) }
|
|
end
|
|
end
|
|
|
|
# The primary key and inheritance column can never be set by mass-assignment for security reasons.
|
|
def attributes_protected_by_default
|
|
[ self.class.primary_key, self.class.inheritance_column ]
|
|
end
|
|
|
|
# Returns copy of the attributes hash where all the values have been safely quoted for use in
|
|
# an SQL statement.
|
|
def attributes_with_quotes(include_primary_key = true)
|
|
attributes.inject({}) do |quoted, (name, value)|
|
|
if column = column_for_attribute(name)
|
|
quoted[name] = quote(value, column) unless !include_primary_key && name == self.class.primary_key
|
|
end
|
|
quoted
|
|
end
|
|
end
|
|
|
|
# Quote strings appropriately for SQL statements.
|
|
def quote(value, column = nil)
|
|
self.class.connection.quote(value, column)
|
|
end
|
|
|
|
# Interpolate custom sql string in instance context.
|
|
# Optional record argument is meant for custom insert_sql.
|
|
def interpolate_sql(sql, record = nil)
|
|
instance_eval("%(#{sql})")
|
|
end
|
|
|
|
# Initializes the attributes array with keys matching the columns from the linked table and
|
|
# the values matching the corresponding default value of that column, so
|
|
# that a new instance, or one populated from a passed-in Hash, still has all the attributes
|
|
# that instances loaded from the database would.
|
|
def attributes_from_column_definition
|
|
connection.columns(self.class.table_name, "#{self.class.name} Columns").inject({}) do |attributes, column|
|
|
attributes[column.name] = column.default unless column.name == self.class.primary_key
|
|
attributes
|
|
end
|
|
end
|
|
|
|
# Instantiates objects for all attribute classes that needs more than one constructor parameter. This is done
|
|
# by calling new on the column type or aggregation type (through composed_of) object with these parameters.
|
|
# So having the pairs written_on(1) = "2004", written_on(2) = "6", written_on(3) = "24", will instantiate
|
|
# written_on (a date type) with Date.new("2004", "6", "24"). You can also specify a typecast character in the
|
|
# parentheses to have the parameters typecasted before they're used in the constructor. Use i for Fixnum, f for Float,
|
|
# s for String, and a for Array. If all the values for a given attribute is empty, the attribute will be set to nil.
|
|
def assign_multiparameter_attributes(pairs)
|
|
execute_callstack_for_multiparameter_attributes(
|
|
extract_callstack_for_multiparameter_attributes(pairs)
|
|
)
|
|
end
|
|
|
|
# Includes an ugly hack for Time.local instead of Time.new because the latter is reserved by Time itself.
|
|
def execute_callstack_for_multiparameter_attributes(callstack)
|
|
errors = []
|
|
callstack.each do |name, values|
|
|
klass = (self.class.reflect_on_aggregation(name) || column_for_attribute(name)).klass
|
|
if values.empty?
|
|
send(name + "=", nil)
|
|
else
|
|
begin
|
|
send(name + "=", Time == klass ? klass.local(*values) : klass.new(*values))
|
|
rescue => ex
|
|
errors << AttributeAssignmentError.new("error on assignment #{values.inspect} to #{name}", ex, name)
|
|
end
|
|
end
|
|
end
|
|
unless errors.empty?
|
|
raise MultiparameterAssignmentErrors.new(errors), "#{errors.size} error(s) on assignment of multiparameter attributes"
|
|
end
|
|
end
|
|
|
|
def extract_callstack_for_multiparameter_attributes(pairs)
|
|
attributes = { }
|
|
|
|
for pair in pairs
|
|
multiparameter_name, value = pair
|
|
attribute_name = multiparameter_name.split("(").first
|
|
attributes[attribute_name] = [] unless attributes.include?(attribute_name)
|
|
|
|
unless value.empty?
|
|
attributes[attribute_name] <<
|
|
[ find_parameter_position(multiparameter_name), type_cast_attribute_value(multiparameter_name, value) ]
|
|
end
|
|
end
|
|
|
|
attributes.each { |name, values| attributes[name] = values.sort_by{ |v| v.first }.collect { |v| v.last } }
|
|
end
|
|
|
|
def type_cast_attribute_value(multiparameter_name, value)
|
|
multiparameter_name =~ /\([0-9]*([a-z])\)/ ? value.send("to_" + $1) : value
|
|
end
|
|
|
|
def find_parameter_position(multiparameter_name)
|
|
multiparameter_name.scan(/\(([0-9]*).*\)/).first.first
|
|
end
|
|
|
|
# Returns a comma-separated pair list, like "key1 = val1, key2 = val2".
|
|
def comma_pair_list(hash)
|
|
hash.inject([]) { |list, pair| list << "#{pair.first} = #{pair.last}" }.join(", ")
|
|
end
|
|
|
|
def quoted_column_names(attributes = attributes_with_quotes)
|
|
attributes.keys.collect do |column_name|
|
|
self.class.connection.quote_column_name(column_name)
|
|
end
|
|
end
|
|
|
|
def quote_columns(quoter, hash)
|
|
hash.inject({}) do |quoted, (name, value)|
|
|
quoted[quoter.quote_column_name(name)] = value
|
|
quoted
|
|
end
|
|
end
|
|
|
|
def quoted_comma_pair_list(quoter, hash)
|
|
comma_pair_list(quote_columns(quoter, hash))
|
|
end
|
|
|
|
def object_from_yaml(string)
|
|
return string unless string.is_a?(String)
|
|
if has_yaml_encoding_header?(string)
|
|
begin
|
|
YAML::load(string)
|
|
rescue Object
|
|
# Apparently wasn't YAML anyway
|
|
string
|
|
end
|
|
else
|
|
string
|
|
end
|
|
end
|
|
|
|
def has_yaml_encoding_header?(string)
|
|
string[0..3] == "--- "
|
|
end
|
|
|
|
def clone_attributes(reader_method = :read_attribute, attributes = {})
|
|
self.attribute_names.inject(attributes) do |attributes, name|
|
|
attributes[name] = clone_attribute_value(reader_method, name)
|
|
attributes
|
|
end
|
|
end
|
|
|
|
def clone_attribute_value(reader_method, attribute_name)
|
|
value = send(reader_method, attribute_name)
|
|
value.clone
|
|
rescue TypeError, NoMethodError
|
|
value
|
|
end
|
|
end
|
|
end
|