Module: Entrails::ActionController::TemplateForReferer

Defined in:

lib/entrails/action_controller/template_for_referer.rb

Overview

TemplateForReferer, when included in ActionController::Base patches the built-in default_template_name method, which is used to determine what template to use in the app/views folder. It does this so that we can create special templates to respond to requests coming from specific named routes.

Why? This can be useful when managing responses for requests coming to the same controller action from multiple contexts. This was created primarily to deal with context in an AJAX setting, where the javascript returned by an RJS file will depend on the current page in the browser, since you may be changing DOM structures specific to that page.

Consider a social network site where you want to support giving users the ability to friend each other. You’ll probably have a friendships resource which will respond to a post method, and you may want to support doing so via AJAX. Well in one case there may be an “add as friend” button on the user profile, which reacts by flipping the button to “remove friend”. In another case you may have many buttons in a list which respond by redrawing the list and adding the new friend in another list.

The solution provided by this module is to allow you to define templates based on the named_route from which the request is being issued/refered. So in the case of the button on the user profile, which would probably by the ‘user’ named route, you would define a create_for_user.js.rjs template to handle it in app/views/friendships. In the case of the list, say the users named route (i.e. the index of users), app/views/friendships/create_for_users.js.rjs

If there is no specific template for the referer’s named route or if the referer is not the local application, (determined by request.host) then we just revert to the default_template_name originally provided by Rails.

Note that this behavior is not enabled just for rjs templates– You can use it for any formats.

Rails uses the controller and action names to determine the name of the template to load.