diff options
Diffstat (limited to 'actionpack')
| -rw-r--r-- | actionpack/lib/action_controller/metal/mime_responds.rb | 135 |
1 files changed, 116 insertions, 19 deletions
diff --git a/actionpack/lib/action_controller/metal/mime_responds.rb b/actionpack/lib/action_controller/metal/mime_responds.rb index 73e044a092..fbb5d01e86 100644 --- a/actionpack/lib/action_controller/metal/mime_responds.rb +++ b/actionpack/lib/action_controller/metal/mime_responds.rb @@ -195,20 +195,106 @@ module ActionController #:nodoc: end end - # respond_with wraps a resource around a responder for default representation. - # First it invokes respond_to, if a response cannot be found (ie. no block - # for the request was given and template was not available), it instantiates - # an ActionController::Responder with the controller and resource. + # For a given controller action, respond_with generates an appropriate + # response based on the mime-type requested by the client. # - # ==== Example + # If the method is called with just a resource, as in this example - # - # def index - # @users = User.all - # respond_with(@users) + # class PeopleController < ApplicationController + # respond_to :html, :xml, :json + # + # def index + # @people = Person.all + # respond_with @people + # end # end # - # It also accepts a block to be given. It's used to overwrite a default - # response: + # then the mime-type of the response is typically selected based on the + # request's Accept header and the set of available formats declared + # by previous calls to the controller's class method +respond_to+. Alternatively + # the mime-type can be selected by explicitly setting <tt>request.format</tt> in + # the controller. + # + # If an acceptable format is not identified, the application returns a + # '406 - not acceptable' status. Otherwise, the default response is to render + # a template named after the current action and the selected format, + # e.g. <tt>index.html.erb</tt>. If no template is available, the behavior + # depends on the selected format: + # + # * for an html response - if the request method is +get+, an exception + # is raised but for other requests such as +post+ the response + # depends on whether the resource has any validation errors (i.e. + # assuming that an attempt has been made to save the resource, + # e.g. by a +create+ action) - + # 1. If there are no errors, i.e. the resource + # was saved successfully, the response +redirect+'s to the resource + # i.e. its +show+ action. + # 2. If there are validation errors, the response + # renders a default action, which is <tt>:new</tt> for a + # +post+ request or <tt>:edit</tt> for +put+. + # Thus an example like this - + # + # respond_to :html, :xml + # + # def create + # @user = User.new(params[:user]) + # flash[:notice] = 'User was successfully created.' if @user.save + # respond_with(@user) + # end + # + # is equivalent, in the absence of <tt>create.html.erb</tt>, to - + # + # def create + # @user = User.new(params[:user]) + # respond_to do |format| + # if @user.save + # flash[:notice] = 'User was successfully created.' + # format.html { redirect_to(@user) } + # format.xml { render :xml => @user } + # else + # format.html { render :action => "new" } + # format.xml { render :xml => @user } + # end + # end + # end + # + # * for a javascript request - if the template isn't found, an exception is + # raised. + # * for other requests - i.e. data formats such as xml, json, csv etc, if + # the resource passed to +respond_with+ responds to <code>to_<format></code>, + # the method attempts to render the resource in the requested format + # directly, e.g. for an xml request, the response is equivalent to calling + # <code>render :xml => resource</code>. + # + # === Nested resources + # + # As outlined above, the +resources+ argument passed to +respond_with+ + # can play two roles. It can be used to generate the redirect url + # for successful html requests (e.g. for +create+ actions when + # no template exists), while for formats other than html and javascript + # it is the object that gets rendered, by being converted directly to the + # required format (again assuming no template exists). + # + # For redirecting successful html requests, +respond_with+ also supports + # the use of nested resources, which are supplied in the same way as + # in <code>form_for</code> and <code>polymorphic_url</code>. For example - + # + # def create + # @project = Project.find(params[:project_id]) + # @task = @project.comments.build(params[:task]) + # flash[:notice] = 'Task was successfully created.' if @task.save + # respond_with(@project, @task) + # end + # + # This would cause +respond_with+ to redirect to <code>project_task_url</code> + # instead of <code>task_url</code>. For request formats other than html or + # javascript, if multiple resources are passed in this way, it is the last + # one specified that is rendered. + # + # === Customizing response behavior + # + # Like +respond_to+, +respond_with+ may also be called with a block that + # can be used to overwrite any of the default responses, e.g. - # # def create # @user = User.new(params[:user]) @@ -219,13 +305,24 @@ module ActionController #:nodoc: # end # end # - # All options given to respond_with are sent to the underlying responder, - # except for the option :responder itself. Since the responder interface - # is quite simple (it just needs to respond to call), you can even give - # a proc to it. - # - # In order to use respond_with, first you need to declare the formats your - # controller responds to in the class level with a call to <tt>respond_to</tt>. + # The argument passed to the block is an ActionController::MimeResponds::Collector + # object which stores the responses for the formats defined within the + # block. Note that formats with responses defined explicitly in this way + # do not have to first be declared using the class method +respond_to+. + # + # Also, a hash passed to +respond_with+ immediately after the specified + # resource(s) is interpreted as a set of options relevant to all + # formats. Any option accepted by +render+ can be used, e.g. + # respond_with @people, :status => 200 + # However, note that these options are ignored after an unsuccessful attempt + # to save a resource, e.g. when automatically rendering <tt>:new</tt> + # after a post request. + # + # Two additional options are relevant specifically to +respond_with+ - + # 1. <tt>:location</tt> - overwrites the default redirect location used after + # a successful html +post+ request. + # 2. <tt>:action</tt> - overwrites the default render action used after an + # unsuccessful html +post+ request. # def respond_with(*resources, &block) raise "In order to use respond_with, first you need to declare the formats your " << @@ -283,8 +380,8 @@ module ActionController #:nodoc: end end - # A container of responses available for requests with different mime-types - # sent to the current controller action. + # A container for responses available from the current controller for + # requests for different mime-types sent to a particular action. # # The public controller methods +respond_with+ and +respond_to+ may be called # with a block that is used to define responses to different mime-types, e.g. |