Method: ActiveResource::Collection#initialize

Defined in:

lib/active_resource/collection.rb

#initialize(elements = []) ⇒ Collection

ActiveResource::Collection is a wrapper to handle parsing index responses that do not directly map to Rails conventions.

You can define a custom class that inherets from ActiveResource::Collection in order to to set the elements instance.

GET /posts.json delivers following response body:

{
  posts: [
    {
      title: "ActiveResource now has associations",
      body: "Lorem Ipsum"
    },
    {...}
  ],
  next_page: "/posts.json?page=2"
}

A Post class can be setup to handle it with:

class Post < ActiveResource::Base
  self.site = "http://example.com"
  self.collection_parser = PostCollection
end

And the collection parser:

class PostCollection < ActiveResource::Collection
  attr_accessor :next_page
  def initialize(parsed = {})
    @elements = parsed['posts']
    @next_page = parsed['next_page']
  end
end

The result from a find method that returns multiple entries will now be a PostParser instance. ActiveResource::Collection includes Enumerable and instances can be iterated over just like an array.

@posts = Post.find(:all) # => PostCollection:xxx
@posts.next_page         # => "/posts.json?page=2"
@posts.map(&:id)         # =>[1, 3, 5 ...]

The initialize method will receive the ActiveResource::Formats parsed result and should set @elements.

# File 'lib/active_resource/collection.rb', line 59

def initialize(elements = [])
  @elements = elements
end