diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index 726b2c19c9..90fef28e3e 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,7 @@
*SVN*
+* Added pagination support through both a controller and helper add-on #817 [Sam Stephenson]
+
* Fixed routing and helpers to make Rails work on non-vhost setups #826 [Nicholas Seckar/Tobias Luetke]
* Added a much improved Flash module that allows for finer-grained control on expiration and allows you to flash the current action #839 [Caio Chassot]. Example of flash.now:
diff --git a/actionpack/lib/action_controller.rb b/actionpack/lib/action_controller.rb
index c9e4f8b9ef..eccd05702f 100755
--- a/actionpack/lib/action_controller.rb
+++ b/actionpack/lib/action_controller.rb
@@ -39,6 +39,7 @@ require 'action_controller/layout'
require 'action_controller/flash'
require 'action_controller/session'
require 'action_controller/dependencies'
+require 'action_controller/pagination'
require 'action_controller/scaffolding'
require 'action_controller/helpers'
require 'action_controller/cookies'
@@ -56,6 +57,7 @@ ActionController::Base.class_eval do
include ActionController::Benchmarking
include ActionController::Rescue
include ActionController::Dependencies
+ include ActionController::Pagination
include ActionController::Scaffolding
include ActionController::Helpers
include ActionController::Cookies
diff --git a/actionpack/lib/action_controller/pagination.rb b/actionpack/lib/action_controller/pagination.rb
new file mode 100644
index 0000000000..54324975e0
--- /dev/null
+++ b/actionpack/lib/action_controller/pagination.rb
@@ -0,0 +1,378 @@
+module ActionController
+ # === Action Pack pagination for Active Record collections
+ #
+ # The Pagination module aids in the process of paging large collections of
+ # Active Record objects. It offers macro-style automatic fetching of your
+ # model for multiple views, or explicit fetching for single actions. And if
+ # the magic isn't flexible enough for your needs, you can create your own
+ # paginators with a minimal amount of code.
+ #
+ # The Pagination module can handle as much or as little as you wish. In the
+ # controller, have it automatically query your model for pagination; or,
+ # if you prefer, create Paginator objects yourself.
+ #
+ # For help rendering pagination links, see
+ # ActionView::Helpers::PaginationHelper.
+ #
+ # ==== Automatic pagination for every action in a controller
+ #
+ # class PersonController < ApplicationController
+ # helper :pagination
+ # model :person
+ #
+ # paginate :people, :order_by => 'last_name, first_name',
+ # :per_page => 20
+ #
+ # # ...
+ # end
+ #
+ # Each action in this controller now has access to a @people
+ # instance variable, which is an ordered collection of model objects for the
+ # current page (at most 20, sorted by last name and first name), and a
+ # @person_pages Paginator instance. The current page is determined
+ # by the @params['page'] variable.
+ #
+ # ==== Pagination for a single action
+ #
+ # def list
+ # @person_pages, @people =
+ # paginate :people, :order_by => 'last_name, first_name'
+ # end
+ #
+ # Like the previous example, but explicitly creates @person_pages
+ # and @people for a single action, and uses the default of 10 items
+ # per page.
+ #
+ # ==== Custom/"classic" pagination
+ #
+ # def list
+ # @person_pages = Paginator.new self, Person.count, 10, @params['page']
+ # @people = Person.find_all nil, 'last_name, first_name',
+ # @person_pages.current.to_sql
+ # end
+ #
+ # Explicitly creates the paginator from the previous example and uses
+ # Paginator#to_sql to retrieve @people from the model.
+ #
+ module Pagination
+ unless const_defined?(:OPTIONS)
+ # A hash holding options for controllers using macro-style pagination
+ OPTIONS = Hash.new
+
+ # The default options for pagination
+ DEFAULT_OPTIONS = {
+ :class_name => nil,
+ :per_page => 10,
+ :conditions => nil,
+ :order_by => nil,
+ :join => nil,
+ :parameter => 'page'
+ }
+ end
+
+ def self.included(base) #:nodoc:
+ super
+ base.extend(ClassMethods)
+ end
+
+ def self.validate_options!(collection_id, options, in_action) #:nodoc:
+ options.merge!(DEFAULT_OPTIONS) {|key, old, new| old}
+
+ valid_options = DEFAULT_OPTIONS.keys
+ valid_options << :actions unless in_action
+
+ unknown_option_keys = options.keys - valid_options
+ raise ActionController::ActionControllerError,
+ "Unknown options: #{unknown_option_keys.join(', ')}" unless
+ unknown_option_keys.empty?
+
+ options[:singular_name] = Inflector.singularize(collection_id.to_s)
+ options[:class_name] ||= Inflector.camelize(options[:singular_name])
+ end
+
+ # Returns a paginator and a collection of Active Record model instances
+ # for the paginator's current page. This is designed to be used in a
+ # single action; to automatically paginate multiple actions, consider
+ # ClassMethods#paginate.
+ #
+ # +options+ are:
+ # :class_name:: the class name to use, if it can't be inferred by
+ # singularizing the collection name
+ # :per_page:: the maximum number of items to include in a
+ # single page. Defaults to 10
+ # :conditions:: optional conditions passed to Model.find_all and
+ # Model.count
+ # :order_by:: optional order parameter passed to Model.find_all
+ # :join:: optional join parameter passed to Model.find_all
+ # and Model.count
+ def paginate(collection_id, options={})
+ Pagination.validate_options!(collection_id, options, true)
+ paginator_and_collection_for(collection_id, options)
+ end
+
+ # These methods become class methods on any controller which includes
+ # PaginationHelper.
+ module ClassMethods
+ # Creates a +before_filter+ which automatically paginates an Active
+ # Record model for all actions in a controller (or certain actions if
+ # specified with the :actions option).
+ #
+ # +options+ are the same as PaginationHelper#paginate, with the addition
+ # of:
+ # :actions:: an array of actions for which the pagination is
+ # active. Defaults to +nil+ (i.e., every action)
+ def paginate(collection_id, options={})
+ Pagination.validate_options!(collection_id, options, false)
+ module_eval do
+ before_filter :create_paginators_and_retrieve_collections
+ OPTIONS[self] ||= Hash.new
+ OPTIONS[self][collection_id] = options
+ end
+ end
+ end
+
+ def create_paginators_and_retrieve_collections #:nodoc:
+ Pagination::OPTIONS[self.class].each do |collection_id, options|
+ next unless options[:actions].include? action_name if
+ options[:actions]
+
+ paginator, collection =
+ paginator_and_collection_for(collection_id, options)
+
+ paginator_name = "@#{options[:singular_name]}_pages"
+ self.instance_variable_set(paginator_name, paginator)
+
+ collection_name = "@#{collection_id.to_s}"
+ self.instance_variable_set(collection_name, collection)
+ end
+ end
+
+ # Returns the total number of items in the collection to be paginated for
+ # the +model+ and given +conditions+. Override this method to implement a
+ # custom counter.
+ def count_collection_for_pagination(model, conditions)
+ model.count(conditions)
+ end
+
+ # Returns a collection of items for the given +model+ and +conditions+,
+ # ordered by +order_by+, for the current page in the given +paginator+.
+ # Override this method to implement a custom finder.
+ def find_collection_for_pagination(model, conditions, order_by, join, paginator)
+ model.find_all(conditions, order_by, paginator.current.to_sql, join)
+ end
+
+ protected :create_paginators_and_retrieve_collections,
+ :count_collection_for_pagination,
+ :find_collection_for_pagination
+
+ def paginator_and_collection_for(collection_id, options) #:nodoc:
+ klass = eval options[:class_name]
+ page = @params[options[:parameter]]
+ count = count_collection_for_pagination(klass, options[:conditions])
+
+ paginator = Paginator.new(self, count, options[:per_page], page)
+
+ collection = find_collection_for_pagination(klass,
+ options[:conditions], options[:order_by], options[:join], paginator)
+
+ return paginator, collection
+ end
+
+ private :paginator_and_collection_for
+
+ # A class representing a paginator for an Active Record collection.
+ class Paginator
+ include Enumerable
+
+ # Creates a new Paginator on the given +controller+ for a set of items
+ # of size +item_count+ and having +items_per_page+ items per page.
+ # Raises ArgumentError if items_per_page is out of bounds (i.e., less
+ # than or equal to zero). The page CGI parameter for links defaults to
+ # "page" and can be overridden with +page_parameter+.
+ def initialize(controller, item_count, items_per_page, current_page=1)
+ raise ArgumentError, 'must have at least one item per page' if
+ items_per_page <= 0
+
+ @controller = controller
+ @item_count = item_count || 0
+ @items_per_page = items_per_page
+
+ self.current_page = current_page
+ end
+ attr_reader :controller, :item_count, :items_per_page
+
+ # Sets the current page number of this paginator. If +page+ is a Page
+ # object, its +number+ attribute is used as the value; if the page does
+ # not belong to this Paginator, an ArgumentError is raised.
+ def current_page=(page)
+ if page.is_a? Page
+ raise ArgumentError, 'Page/Paginator mismatch' unless
+ page.paginator == self
+ end
+ page = page.to_i
+ @current_page = has_page_number?(page) ? page : 1
+ end
+
+ # Returns a Page object representing this paginator's current page.
+ def current_page
+ self[@current_page]
+ end
+ alias current :current_page
+
+ # Returns a new Page representing the first page in this paginator.
+ def first_page
+ self[1]
+ end
+ alias first :first_page
+
+ # Returns a new Page representing the last page in this paginator.
+ def last_page
+ self[page_count]
+ end
+ alias last :last_page
+
+ # Returns the number of pages in this paginator.
+ def page_count
+ return 1 if @item_count.zero?
+ (@item_count / @items_per_page.to_f).ceil
+ end
+ alias length :page_count
+
+ # Returns true if this paginator contains the page of index +number+.
+ def has_page_number?(number)
+ return false unless number.is_a? Fixnum
+ number >= 1 and number <= page_count
+ end
+
+ # Returns a new Page representing the page with the given index
+ # +number+.
+ def [](number)
+ Page.new(self, number)
+ end
+
+ # Successively yields all the paginator's pages to the given block.
+ def each(&block)
+ page_count.times do |n|
+ yield self[n+1]
+ end
+ end
+
+ # A class representing a single page in a paginator.
+ class Page
+ include Comparable
+
+ # Creates a new Page for the given +paginator+ with the index
+ # +number+. If +number+ is not in the range of valid page numbers or
+ # is not a number at all, it defaults to 1.
+ def initialize(paginator, number)
+ @paginator = paginator
+ @number = number.to_i
+ @number = 1 unless @paginator.has_page_number? @number
+ end
+ attr_reader :paginator, :number
+ alias to_i :number
+
+ # Compares two Page objects and returns true when they represent the
+ # same page (i.e., their paginators are the same and they have the
+ # same page number).
+ def ==(page)
+ return false if page.nil?
+ @paginator == page.paginator and
+ @number == page.number
+ end
+
+ # Compares two Page objects and returns -1 if the left-hand page comes
+ # before the right-hand page, 0 if the pages are equal, and 1 if the
+ # left-hand page comes after the right-hand page. Raises ArgumentError
+ # if the pages do not belong to the same Paginator object.
+ def <=>(page)
+ raise ArgumentError unless @paginator == page.paginator
+ @number <=> page.number
+ end
+
+ # Returns the item offset for the first item in this page.
+ def offset
+ @paginator.items_per_page * (@number - 1)
+ end
+
+ # Returns the number of the first item displayed.
+ def first_item
+ offset + 1
+ end
+
+ # Returns the number of the last item displayed.
+ def last_item
+ [@paginator.items_per_page * @number, @paginator.item_count].min
+ end
+
+ # Returns true if this page is the first page in the paginator.
+ def first?
+ self == @paginator.first
+ end
+
+ # Returns true if this page is the last page in the paginator.
+ def last?
+ self == @paginator.last
+ end
+
+ # Returns a new Page object representing the page just before this
+ # page, or nil if this is the first page.
+ def previous
+ if first? then nil else Page.new(@paginator, @number - 1) end
+ end
+
+ # Returns a new Page object representing the page just after this
+ # page, or nil if this is the last page.
+ def next
+ if last? then nil else Page.new(@paginator, @number + 1) end
+ end
+
+ # Returns a new Window object for this page with the specified
+ # +padding+.
+ def window(padding=2)
+ Window.new(self, padding)
+ end
+
+ # Returns the limit/offset array for this page.
+ def to_sql
+ [@paginator.items_per_page, offset]
+ end
+
+ def to_param #:nodoc:
+ @number.to_s
+ end
+ end
+
+ # A class for representing ranges around a given page.
+ class Window
+ # Creates a new Window object for the given +page+ with the specified
+ # +padding+.
+ def initialize(page, padding=2)
+ @paginator = page.paginator
+ @page = page
+ self.padding = padding
+ end
+ attr_reader :paginator, :page
+
+ # Sets the window's padding (the number of pages on either side of the
+ # window page).
+ def padding=(padding)
+ @padding = padding < 0 ? 0 : padding
+ # Find the beginning and end pages of the window
+ @first = @paginator.has_page_number?(@page.number - @padding) ?
+ @paginator[@page.number - @padding] : @paginator.first
+ @last = @paginator.has_page_number?(@page.number + @padding) ?
+ @paginator[@page.number + @padding] : @paginator.last
+ end
+ attr_reader :padding, :first, :last
+
+ # Returns an array of Page objects in the current window.
+ def pages
+ (@first.number..@last.number).to_a.map {|n| @paginator[n]}
+ end
+ alias to_a :pages
+ end
+ end
+
+ end
+end
diff --git a/actionpack/lib/action_view/helpers/pagination_helper.rb b/actionpack/lib/action_view/helpers/pagination_helper.rb
new file mode 100644
index 0000000000..cb3c3807eb
--- /dev/null
+++ b/actionpack/lib/action_view/helpers/pagination_helper.rb
@@ -0,0 +1,65 @@
+module ActionView
+ module Helpers
+ # Provides methods for linking to ActionController::Pagination objects.
+ module PaginationHelper
+ unless const_defined?(:DEFAULT_OPTIONS)
+ DEFAULT_OPTIONS = {
+ :name => :page,
+ :window_size => 2,
+ :always_show_anchors => true,
+ :link_to_current_page => false,
+ :params => {}
+ }
+ end
+
+ # Creates a basic HTML link bar for the given +paginator+.
+ #
+ # +options+ are:
+ # :name:: the routing name for this paginator
+ # (defaults to +page+)
+ # :window_size:: the number of pages to show around
+ # the current page (defaults to +2+)
+ # :always_show_anchors:: whether or not the first and last
+ # pages should always be shown
+ # (defaults to +true+)
+ # :link_to_current_page:: whether or not the current page
+ # should be linked to (defaults to
+ # +false+)
+ # :pararms:: any additional routing parameters
+ # for page URLs
+ def pagination_links(paginator, options={})
+ options.merge!(DEFAULT_OPTIONS) {|key, old, new| old}
+
+ window_pages = paginator.current.window(options[:window_size]).pages
+
+ return if window_pages.length <= 1 unless
+ options[:link_to_current_page]
+
+ first, last = paginator.first, paginator.last
+
+ returning html = '' do
+ if options[:always_show_anchors] and not window_pages[0].first?
+ html << link_to(first.number, options[:name] => first)
+ html << ' ... ' if window_pages[0].number - first.number > 1
+ html << ' '
+ end
+
+ window_pages.each do |page|
+ if paginator.current == page && !options[:link_to_current_page]
+ html << page.number.to_s
+ else
+ html << link_to(page.number, options[:name] => page)
+ end
+ html << ' '
+ end
+
+ if options[:always_show_anchors] && !window_pages.last.last?
+ html << ' ... ' if last.number - window_pages[-1].number > 1
+ html << link_to(paginator.last.number, options[:name] => last)
+ end
+ end
+ end
+
+ end
+ end
+end
diff --git a/activesupport/lib/active_support/core_ext/kernel.rb b/activesupport/lib/active_support/core_ext/kernel.rb
new file mode 100644
index 0000000000..fe6f725bc0
--- /dev/null
+++ b/activesupport/lib/active_support/core_ext/kernel.rb
@@ -0,0 +1,17 @@
+module Kernel
+ # A Ruby-ized realization of the K combinator, courtesy of Mikael Brockman.
+ #
+ # def foo
+ # returning values = [] do
+ # values << 'bar'
+ # values << 'baz'
+ # end
+ # end
+ #
+ # foo # => ['bar', 'baz']
+ #
+ def returning(value) #:nodoc:
+ yield
+ value
+ end
+end