Instance Public methods
direct(name, options = {}, &block) Link
Define custom URL helpers that will be added to the application’s routes. This allows you to override and/or replace the default behavior of routing helpers, e.g:
direct :homepage do
"https://rubyonrails.org"
end
direct :commentable do |model|
[ model, anchor: model.dom_id ]
end
direct :main do
{ controller: "pages", action: "index", subdomain: "www" }
end
The return value from the block passed to direct
must be a valid set of arguments for url_for
which will actually build the URL string. This can be one of the following:
-
A string, which is treated as a generated URL
-
A hash, e.g.
{ controller: "pages", action: "index" }
-
An array, which is passed to
polymorphic_url
-
An Active Model instance
-
An Active Model class
NOTE: Other URL helpers can be called in the block but be careful not to invoke your custom URL helper again otherwise it will result in a stack overflow error.
You can also specify default options that will be passed through to your URL helper definition, e.g:
direct :browse, page: 1, size: 10 do |options|
[ :products, options.merge(params.permit(:page, :size).to_h.symbolize_keys) ]
end
In this instance the params
object comes from the context in which the block is executed, e.g. generating a URL inside a controller action or a view. If the block is executed where there isn’t a params
object such as this:
Rails.application.routes.url_helpers.browse_path
then it will raise a NameError
. Because of this you need to be aware of the context in which you will use your custom URL helper when defining it.
NOTE: The direct
method can’t be used inside of a scope block such as namespace
or scope
and will raise an error if it detects that it is.
resolve(*args, &block) Link
Define custom polymorphic mappings of models to URLs. This alters the behavior of polymorphic_url
and consequently the behavior of link_to
and form_for
when passed a model instance, e.g:
resource :basket
resolve "Basket" do
[:basket]
end
This will now generate “/basket” when a Basket
instance is passed to link_to
or form_for
instead of the standard “/baskets/:id”.
NOTE: This custom behavior only applies to simple polymorphic URLs where a single model instance is passed and not more complicated forms, e.g:
# config/routes.rb
resource :profile
namespace :admin do
resources :users
end
resolve("User") { [:profile] }
# app/views/application/_menu.html.erb
link_to "Profile", @current_user
link_to "Profile", [:admin, @current_user]
The first link_to
will generate “/profile” but the second will generate the standard polymorphic URL of “/admin/users/1”.
You can pass options to a polymorphic mapping - the arity for the block needs to be two as the instance is passed as the first argument, e.g:
resolve "Basket", anchor: "items" do |basket, options|
[:basket, options]
end
This generates the URL “/basket#items” because when the last item in an array passed to polymorphic_url
is a hash then it’s treated as options to the URL helper that gets called.
NOTE: The resolve
method can’t be used inside of a scope block such as namespace
or scope
and will raise an error if it detects that it is.
# File actionpack/lib/action_dispatch/routing/mapper.rb, line 2246 def resolve(*args, &block) unless @scope.root? raise RuntimeError, "The resolve method can't be used inside a routes scope block" end options = args.extract_options! args = args.flatten(1) args.each do |klass| @set.add_polymorphic_mapping(klass, options, &block) end end