Rails 3 Controller: Difference between revisions

Latest revision as of 22:20, 6 July 2011

Routes

defined in config/routes.rb:

match ':controller(/:action(/:id(.:format)))'  # default route, :id and :format may be accessed as parameters in the action
match '/teams/home' => 'teams#index'           # call index action of teams controller
match '/teams/search/:query' => 'teams#search' # sends :query parameter to search action in teams controller
match '/teams/search/:query' => 'teams#search', :as => 'search'  # named route, defines search_url and search_path methods

search_url  => http://example.com/teams/search
search_path => /teams/search

useful in something like

link_to "Search", search_path

root url

use something like this in config/routes.rb:

root :to => "articles#index"

NOTE: You must also delete /public/index.html to make sure the web server doesn't bypass Rails.

RESTful Routes and Resources

If you add

resources :articles

to config/routes.rb, the following named routes are automatically created:

article_path => /articles/:id  
articles_path => /articles  
edit_article_path => /articles/edit/:id  
new_article_path => /articles/new

If you generate a scaffold, you will get all seven of the default actions for RESTful controllers: index, show, new, edit, create, update, and destroy

Nested Resources

The Comment object depends on the Article object, so create a nested resource in config/routes.rb:

resources :articles do
    resources :comments 
end

This creates the following named routes:

article_comments_path
article_comment_path
edit_article_comment_path
new_article_comment_path

Redirecting

Use an object as shorthand for redirection:

redirect_to(@article)

is a shortcut equivalent to

redirect_to(article_path(:id => @article.id))

Controllers

Generate Controller

rails generate controller ControllerName [actions] [options]

Example:

rails generate controller Users

ApplicationController

Every controller is a subclass of ApplicationController. Any methods or data in ApplicationController are therefore available to all other controllers.

Flash Hash

Useful for sending messages from controller to view. Use this in controller:

flash[:rubber_ducky] = "You're the one!"

and make it visible in the view with

<%= flash[:rubber_ducky] %>

Two special shorthand cases: notice and alert: This code in controller:

format.html { redirect_to(@article, :notice => 'Article was successfully created.') }

and this in view:

<p class="notice"><%= notice %></p>

@@ Line 1: / Line 1: @@
 == Routes ==
 defined in <code>config/routes.rb</code>:
-<pre>
+<source lang="ruby">
 match ':controller(/:action(/:id(.:format)))'  # default route, :id and :format may be accessed as parameters in the action
 match '/teams/home' => 'teams#index'           # call index action of teams controller
 match '/teams/search/:query' => 'teams#search' # sends :query parameter to search action in teams controller
 match '/teams/search/:query' => 'teams#search', :as => 'search'  # named route, defines search_url and search_path methods
+</source>
+<pre>
+search_url  => http://example.com/teams/search
+search_path => /teams/search
 </pre>
-<code>search_url</code> gives <code>http://example.com/teams/search</code>,
-<code>search_path</code> gives <code>/teams/search</code>
 useful in something like
 <source lang="ruby">
 link_to "Search", search_path
+</source>
+=== root url ===
+use something like this in <code>config/routes.rb</code>:
+<source lang="ruby">
+root :to => "articles#index"
+</source>
+NOTE: You must also delete <code>/public/index.html</code> to make sure the web server doesn't bypass Rails.
+=== RESTful Routes and Resources ===
+If you add
+<source lang="ruby">
+resources :articles
+</source>
+to <code>config/routes.rb</code>, the following named routes are automatically created:
+<pre>
+article_path => /articles/:id
+articles_path => /articles
+edit_article_path => /articles/edit/:id
+new_article_path => /articles/new
+</pre>
+If you generate a scaffold, you will get all seven of the default actions for RESTful controllers:
+index, show, new, edit, create, update, and destroy
+==== Nested Resources ====
+The Comment object depends on the Article object, so create a nested resource in <code>config/routes.rb</code>:
+<source lang="ruby">
+resources :articles do
+    resources :comments
+end
+</source>
+This creates the following named routes:
+<pre>
+article_comments_path
+article_comment_path
+edit_article_comment_path
+new_article_comment_path
+</pre>
+=== Redirecting ===
+Use an object as shorthand for redirection:
+<source lang="ruby">
+redirect_to(@article)
+</source>
+is a shortcut equivalent to
+<source lang="ruby">
+redirect_to(article_path(:id => @article.id))
+</source>
+== Controllers ==
+=== Generate Controller ===
+<pre>
+rails generate controller ControllerName [actions] [options]
+</pre>
+Example:
+<pre>
+rails generate controller Users
+</pre>
+=== ApplicationController ===
+Every controller is a subclass of <code>ApplicationController</code>.  Any methods or data in <code>ApplicationController</code> are therefore available to all other controllers.
+=== Flash Hash ===
+Useful for sending messages from controller to view.  Use this in controller:
+<source lang="ruby">
+flash[:rubber_ducky] = "You're the one!"
+</source>
+and make it visible in the view with
+<source lang="ruby">
+<%= flash[:rubber_ducky] %>
+</source>
+Two special shorthand cases: <code>notice</code> and <code>alert</code>:
+This code in controller:
+<source lang="ruby">
+format.html { redirect_to(@article, :notice => 'Article was successfully created.') }
+</source>
+and this in view:
+<source lang="ruby">
+<p class="notice"><%= notice %></p>
 </source>