Rails can route arbitrary URLs to actions.
Regular routes are series of symbols that Rails maps to parts of an HTTP request.
:controller and :action are special, they map to the names of an action within a controller. Example route:
get ‘:controller(/:action(/:id))’
a request /photos/show/1 is processed by this route, invoking show action by PhotosController. 1 is passed through params[:id]
Anything other than :controller or :action is a part of params, as dynamic segments.
get ‘:controller/:action/:id/:user_id’
Any segment in the path not prepended by a colon is static:
get ‘:controller/:action/:id/with_user/:user_id’
responds to path /photos/show/1/with_user/2
Query String acts normally with non-resourceful routes. Query String passed as the final parameter in params. For the route:
get ‘:controller/:action/:id’
the path /photos/show/1?user_id=2 will pass user_id=2 as params to show action in PhotosController
You don’t need to explicitly use :controller and :action symbols in a route. Supplying them by default:
get ‘photos/:id’, to: ‘photos#show’
a path /photos/12 will implicitly match to the show action from PhotosController
You can define other defaults in a route by supplying a hash to the :defaults option. Applies to non-dynamic segments too:
get ‘photos/:id’, to: ‘photos#show’, defaults: { format: ‘jpg’ }
matches path photos/12 to show action of PhotosController, and set params[:format] to ‘jpg’
get ‘exit’, to: ‘sessions#destroy’, as: :logout
creates logout_path and logout_url as named helpers.
logout_path will return /exit path
match 'photos', to: 'photos#show', via: [:get, :post] constrains a rote to particular verbs. via :all will match all verbs.
:constraints option enforces format for a dynamic segment.
get 'photos/:id', to: 'photos#show', constraints: { id: /[A-Z]\d{5}/ }Matches /photos/A12345 but not /photos/893.