Module | ActionController::Routing |
In: |
vendor/rails/actionpack/lib/action_controller/routing.rb
|
The routing module provides URL rewriting in native Ruby. It’s a way to redirect incoming requests to controllers and actions. This replaces mod_rewrite rules. Best of all Rails’ Routing works with any web server. Routes are defined in routes.rb in your RAILS_ROOT/config directory.
Consider the following route, installed by Rails when you generate your application:
map.connect ':controller/:action/:id'
This route states that it expects requests to consist of a :controller followed by an :action that in turns is fed by some :id
Suppose you get an incoming request for /blog/edit/22, you’ll end up with:
params = { :controller => 'blog', :action => 'edit' :id => '22' }
Think of creating routes as drawing a map for your requests. The map tells them where to go based on some predefined pattern:
ActionController::Routing::Routes.draw do |map| Pattern 1 tells some request to go to one place Pattern 2 tell them to go to another ... end
The following symbols are special:
:controller maps to your controller name :action maps to an action with your controllers
Other names simply map to a parameter as in the case of +:id+.
Not all routes are created equally. Routes have priority defined by the order of appearance of the routes in the routes.rb file. The priority goes from top to bottom. The last route in that file is at the lowest priority will be applied last. If no route matches, 404 is returned.
Within blocks, the empty pattern goes first i.e. is at the highest priority. In practice this works out nicely:
ActionController::Routing::Routes.draw do |map| map.with_options :controller => 'blog' do |blog| blog.show '', :action => 'list' end map.connect ':controller/:action/:view end
In this case, invoking blog controller (with an URL like ’/blog/’) without parameters will activate the ‘list’ action by default.
Setting a default route is straightforward in Rails because by appending a Hash to the end of your mapping you can set default parameters.
Example:
ActionController::Routing:Routes.draw do |map| map.connect ':controller/:action/:id', :controller => 'blog' end
This sets up blog as the default controller if no other is specified. This means visiting ’/’ would invoke the blog controller.
More formally, you can define defaults in a route with the +:defaults+ key.
map.connect ':controller/:id/:action', :action => 'show', :defaults => { :page => 'Dashboard' }
Routes can be named with the syntax map.name_of_route options, allowing for easy reference within your source as name_of_route_url.
Example:
# In routes.rb map.login 'login', :controller => 'accounts', :action => 'login' # With render, redirect_to, tests, etc. redirect_to login_url
Arguments can be passed as well.
redirect_to show_item_url(:id => 25)
When using with_options, the name goes after the item passed to the block.
ActionController::Routing::Routes.draw do |map| map.with_options :controller => 'blog' do |blog| blog.show '', :action => 'list' blog.delete 'delete/:id', :action => 'delete', blog.edit 'edit/:id', :action => 'edit' end map.connect ':controller/:action/:view end
You would then use the named routes in your views:
link_to @article.title, show_url(:id => @article.id)
Routes can generate pretty URLs. For example:
map.connect 'articles/:year/:month/:day', :controller => 'articles', :action => 'find_by_date', :year => /\d{4}/, :month => /\d{1,2}/, :day => /\d{1,2}/ # Using the route above, the url below maps to: # params = {:year => '2005', :month => '11', :day => '06'} # http://localhost:3000/articles/2005/11/06
You can specify a reqular expression to define a format for a parameter.
map.geocode 'geocode/:postalcode', :controller => 'geocode', :action => 'show', :postalcode => /\d{5}(-\d{4})?/
or more formally:
map.geocode 'geocode/:postalcode', :controller => 'geocode', :action => 'show', :requirements { :postalcode => /\d{5}(-\d{4})?/ }
Specifying *[string] as part of a rule like :
map.connect '*path' , :controller => 'blog' , :action => 'unrecognized?'
will glob all remaining parts of the route that were not recognized earlier. This idiom must appear at the end of the path. The globbed values are in params[:path] in this case.
You can reload routes if you feel you must:
Action::Controller::Routes.reload
This will clear all named routes and reload routes.rb
The two main methods for testing your routes:
def test_movie_route_properly_splits opts = {:controller => "plugin", :action => "checkout", :id => "2"} assert_routing "plugin/checkout/2", opts end
assert_routing lets you test whether or not the route properly resolves into options.
def test_route_has_options opts = {:controller => "plugin", :action => "show", :id => "12"} assert_recognizes opts, "/plugins/show/12" end
Note the subtle difference between the two: assert_routing tests that an URL fits options while assert_recognizes tests that an URL breaks into parameters properly.
In tests you can simply pass the URL or named route to get or post.
def send_to_jail get '/jail' assert_response :success assert_template "jail/front" end def goes_to_login get login_url #... end
SEPARATORS | = | %w( / ; . , ? ) |
Routes | = | RouteSet.new |
# File vendor/rails/actionpack/lib/action_controller/routing.rb, line 298 298: def controller_relative_to(controller, previous) 299: if controller.nil? then previous 300: elsif controller[0] == ?/ then controller[1..-1] 301: elsif %r{^(.*)/} =~ previous then "#{$1}/#{controller}" 302: else controller 303: end 304: end
# File vendor/rails/actionpack/lib/action_controller/routing.rb, line 252 252: def normalize_paths(paths) 253: # do the hokey-pokey of path normalization... 254: paths = paths.collect do |path| 255: path = path. 256: gsub("//", "/"). # replace double / chars with a single 257: gsub("\\\\", "\\"). # replace double \ chars with a single 258: gsub(%r{(.)[\\/]$}, '\1') # drop final / or \ if path ends with it 259: 260: # eliminate .. paths where possible 261: re = %r{\w+[/\\]\.\.[/\\]} 262: path.gsub!(%r{\w+[/\\]\.\.[/\\]}, "") while path.match(re) 263: path 264: end 265: 266: # start with longest path, first 267: paths = paths.uniq.sort_by { |path| - path.length } 268: end
# File vendor/rails/actionpack/lib/action_controller/routing.rb, line 270 270: def possible_controllers 271: unless @possible_controllers 272: @possible_controllers = [] 273: 274: paths = controller_paths.select { |path| File.directory?(path) && path != "." } 275: 276: seen_paths = Hash.new {|h, k| h[k] = true; false} 277: normalize_paths(paths).each do |load_path| 278: Dir["#{load_path}/**/*_controller.rb"].collect do |path| 279: next if seen_paths[path.gsub(%r{^\.[/\\]}, "")] 280: 281: controller_name = path[(load_path.length + 1)..-1] 282: 283: controller_name.gsub!(/_controller\.rb\Z/, '') 284: @possible_controllers << controller_name 285: end 286: end 287: 288: # remove duplicates 289: @possible_controllers.uniq! 290: end 291: @possible_controllers 292: end
# File vendor/rails/actionpack/lib/action_controller/routing.rb, line 294 294: def use_controllers!(controller_names) 295: @possible_controllers = controller_names 296: end