问题
I have a Rails 3 application with several engines containing additional functionality. Each engine is a separate service that customers can purchase access to.
I am, however, having a problem with routes from the engines that aren't readily available to the controllers and views.
controller:
class ClassroomsController < ApplicationController
..
respond_to :html
def index
respond_with(@classrooms = @company.classrooms.all)
end
def new
respond_with(@classroom = @company.classrooms.build)
end
..
end
app/views/classrooms/new.html.haml
:
= form_for @classroom do |f|
..
f.submit
config/routes.rb
in engine:
MyEngineName::Engine.routes.draw do
resources :classrooms
end
config/routes.rb
in app:
Seabed::Application.routes.draw do
mount MyEngineName::Engine => '/engine'
...
end
lib/my_engine_name.rb
in engine:
module MyEngineName
class Engine < ::Rails::Engine
end
end
attempting to go to /classrooms/new
results in
NoMethodError in Classrooms#new
Showing app/views/classrooms/_form.html.haml where line #1 raised:
undefined method `hash_for_classrooms_path' for #<Module:0x00000104cff0f8>
and attempting to call classrooms_path
from any other view results in the same error.
I can, however, call MyEngineName::Engine.routes.url_helpers.classrooms_path
and get it working. I'm thinking I might have defined the routes wrong, but can't find another way that works.
Tried running the app with both Passenger (standalone and Apache module) and WEBrick (rails server). Using latest Rails from Git (7c920631ec3b314cfaa3a60d265de40cba3e8135
).
回答1:
Change config.routes
in your engine to:
Rails.application.routes.draw do # NOT MyEngineName::Engine.routes.draw
resources :classrooms
end
The way you have it, the routes are only available in the MyEngineName::Engine
namespace and not in the rest of the host rails application.
There used to be a blog post with more info, but unfortunately it is no longer available:
- http://blog.loopedstrange.com/modest-rubyist-archive/rails-3-plugins-part2-writing-an-engine
回答2:
I had the same problem, and found this in the documentation:
Since you can now mount an engine inside application’s routes, you do not have direct access to Engine‘s url_helpers inside Application. When you mount an engine in an application’s routes, a special helper is created to allow you to do that. Consider such a scenario:
# config/routes.rb
MyApplication::Application.routes.draw do
mount MyEngine::Engine => "/my_engine", :as => "my_engine"
get "/foo" => "foo#index"
end
Now, you can use the my_engine helper inside your application:
class FooController < ApplicationController
def index
my_engine.root_url #=> /my_engine/
end
end
回答3:
For me also help to add
require 'engine' if defined?(Rails)
to my main gem file (lib/.rb).
Good example - https://github.com/mankind/Rails-3-engine-example/blob/master/lib/dummy.rb
来源:https://stackoverflow.com/questions/4361050/how-can-i-make-routes-from-a-rails-3-engine-available-to-the-host-application