Question

I am following a neat ruby on rails tutorial about routes. So I am wondering, how does routing know so much?

I have one controller called posts_controller, and a post model. In the routes.rb file, I added

# config/routes.rb
resources :posts

As far as I understood it, this automatically creates the appropriate routings for all the controller actions associated with a post. So far, I have only one method in my posts_controller:

# app/controllers/posts_controller.rb
def index

end

But strangely, when I execute

$ rake routes

it gives me all this:

    posts GET    /posts(.:format)          posts#index
          POST   /posts(.:format)          posts#create
 new_post GET    /posts/new(.:format)      posts#new
edit_post GET    /posts/:id/edit(.:format) posts#edit
     post GET    /posts/:id(.:format)      posts#show
          PUT    /posts/:id(.:format)      posts#update
          DELETE /posts/:id(.:format)      posts#destroy

How does the routing mechanism know so much without ever telling it that I want to able to create and update posts?

Answer 1

Using “resources” has nothing to do with the actions you have defined. It simply creates all of the restful routes you could need in your controller.

As you can see it creates: index, create, new, edit, show, update, and destroy

It’s actually unintelligent since it creates routes for actions which don’t exist.

An example of how to limit it to only actions you need.

resources :posts, :only => [:show, :index]