diff options
Diffstat (limited to 'actionpack/lib')
| -rwxr-xr-x | actionpack/lib/action_controller.rb | 2 | ||||
| -rw-r--r-- | actionpack/lib/action_controller/pagination.rb | 378 | ||||
| -rw-r--r-- | actionpack/lib/action_view/helpers/pagination_helper.rb | 65 |
3 files changed, 445 insertions, 0 deletions
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 <tt>@people</tt> + # 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 + # <tt>@person_pages</tt> Paginator instance. The current page is determined + # by the <tt>@params['page']</tt> 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 <tt>@person_pages</tt> + # and <tt>@people</tt> 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 <tt>@people</tt> 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: + # <tt>:class_name</tt>:: the class name to use, if it can't be inferred by + # singularizing the collection name + # <tt>:per_page</tt>:: the maximum number of items to include in a + # single page. Defaults to 10 + # <tt>:conditions</tt>:: optional conditions passed to Model.find_all and + # Model.count + # <tt>:order_by</tt>:: optional order parameter passed to Model.find_all + # <tt>:join</tt>:: 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 <tt>:actions</tt> option). + # + # +options+ are the same as PaginationHelper#paginate, with the addition + # of: + # <tt>:actions</tt>:: 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: + # <tt>:name</tt>:: the routing name for this paginator + # (defaults to +page+) + # <tt>:window_size</tt>:: the number of pages to show around + # the current page (defaults to +2+) + # <tt>:always_show_anchors</tt>:: whether or not the first and last + # pages should always be shown + # (defaults to +true+) + # <tt>:link_to_current_page</tt>:: whether or not the current page + # should be linked to (defaults to + # +false+) + # <tt>:pararms</tt>:: 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 |