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Diffstat (limited to 'actionpack/lib/action_controller/api.rb')
-rw-r--r-- | actionpack/lib/action_controller/api.rb | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/api.rb b/actionpack/lib/action_controller/api.rb new file mode 100644 index 0000000000..d8149e0232 --- /dev/null +++ b/actionpack/lib/action_controller/api.rb @@ -0,0 +1,145 @@ +require 'action_view' +require 'action_controller' +require 'action_controller/log_subscriber' + +module ActionController + # API Controller is a lightweight version of <tt>ActionController::Base</tt>, + # created for applications that don't require all functionality that a complete + # \Rails controller provides, allowing you to create controllers with just the + # features that you need for API only applications. + # + # An API Controller is different from a normal controller in the sense that + # by default it doesn't include a number of features that are usually required + # by browser access only: layouts and templates rendering, cookies, sessions, + # flash, assets, and so on. This makes the entire controller stack thinner, + # suitable for API applications. It doesn't mean you won't have such + # features if you need them: they're all available for you to include in + # your application, they're just not part of the default API Controller stack. + # + # By default, only the ApplicationController in a \Rails application inherits + # from <tt>ActionController::API</tt>. All other controllers in turn inherit + # from ApplicationController. + # + # A sample controller could look like this: + # + # class PostsController < ApplicationController + # def index + # @posts = Post.all + # render json: @posts + # end + # end + # + # Request, response and parameters objects all work the exact same way as + # <tt>ActionController::Base</tt>. + # + # == Renders + # + # The default API Controller stack includes all renderers, which means you + # can use <tt>render :json</tt> and brothers freely in your controllers. Keep + # in mind that templates are not going to be rendered, so you need to ensure + # your controller is calling either <tt>render</tt> or <tt>redirect</tt> in + # all actions, otherwise it will return 204 No Content response. + # + # def show + # @post = Post.find(params[:id]) + # render json: @post + # end + # + # == Redirects + # + # Redirects are used to move from one action to another. You can use the + # <tt>redirect</tt> method in your controllers in the same way as + # <tt>ActionController::Base</tt>. For example: + # + # def create + # redirect_to root_url and return if not_authorized? + # # do stuff here + # end + # + # == Adding new behavior + # + # In some scenarios you may want to add back some functionality provided by + # <tt>ActionController::Base</tt> that is not present by default in + # <tt>ActionController::API</tt>, for instance <tt>MimeResponds</tt>. This + # module gives you the <tt>respond_to</tt> and <tt>respond_with</tt> methods. + # Adding it is quite simple, you just need to include the module in a specific + # controller or in <tt>ApplicationController</tt> in case you want it + # available to your entire app: + # + # class ApplicationController < ActionController::API + # include ActionController::MimeResponds + # end + # + # class PostsController < ApplicationController + # def index + # @posts = Post.all + # + # respond_to do |format| + # format.json { render json: @posts } + # format.xml { render xml: @posts } + # end + # end + # end + # + # Quite straightforward. Make sure to check <tt>ActionController::Base</tt> + # available modules if you want to include any other functionality that is + # not provided by <tt>ActionController::API</tt> out of the box. + class API < Metal + abstract! + + # Shortcut helper that returns all the ActionController::API modules except the ones passed in the argument: + # + # class MetalController + # ActionController::API.without_modules(:Redirecting, :DataStreaming).each do |left| + # include left + # end + # end + # + # This gives better control over what you want to exclude and makes it easier + # to create an api controller class, instead of listing the modules required manually. + def self.without_modules(*modules) + modules = modules.map do |m| + m.is_a?(Symbol) ? ActionController.const_get(m) : m + end + + MODULES - modules + end + + MODULES = [ + AbstractController::Rendering, + + UrlFor, + Redirecting, + Rendering, + Renderers::All, + ConditionalGet, + RackDelegation, + BasicImplicitRender, + StrongParameters, + + ForceSSL, + DataStreaming, + + # Before callbacks should also be executed the earliest as possible, so + # also include them at the bottom. + AbstractController::Callbacks, + + # Append rescue at the bottom to wrap as much as possible. + Rescue, + + # Add instrumentations hooks at the bottom, to ensure they instrument + # all the methods properly. + Instrumentation, + + # Params wrapper should come before instrumentation so they are + # properly showed in logs + ParamsWrapper + ] + + MODULES.each do |mod| + include mod + end + + ActiveSupport.run_load_hooks(:action_controller, self) + end +end |