How do I write a Rails 3.1 engine controller test in rspec?

Question

I have written a Rails 3.1 engine with the namespace Posts. Hence, my controllers are found in app/controllers/posts/, my models in app/models/posts, etc. I can test the mod

Answer 1

I'm assuming you're testing your engine with a dummy rails app, like the one that would be generated by enginex.

Your engine should be mounted in the dummy app:

In spec/dummy/config/routes.rb:

Dummy::Application.routes.draw do
  mount Posts::Engine => '/posts-prefix'
end

My second assumption is that your engine is isolated:

In lib/posts.rb:

module Posts
  class Engine < Rails::Engine
    isolate_namespace Posts
  end
end

I don't know if these two assumptions are really required, but that is how my own engine is structured.

The workaround is quite simple, instead of this

get :show, :id => 1

use this

get :show, {:id => 1, :use_route => :posts}

The :posts symbol should be the name of your engine and NOT the path where it is mounted.

This works because the get method parameters are passed straight to ActionDispatch::Routing::RouteSet::Generator#initialize (defined here), which in turn uses @named_route to get the correct route from Rack::Mount::RouteSet#generate (see here and here).

Plunging into the rails internals is fun, but quite time consuming, I would not do this every day ;-) .

HTH

Answer 2

I worked around this issue by overriding the get, post, put, and delete methods that are provided, making it so they always pass use_route as a parameter.

I used Benoit's answer as a basis for this. Thanks buddy!

module ControllerHacks
  def get(action, parameters = nil, session = nil, flash = nil)
    process_action(action, parameters, session, flash, "GET")
  end

  # Executes a request simulating POST HTTP method and set/volley the response
  def post(action, parameters = nil, session = nil, flash = nil)
    process_action(action, parameters, session, flash, "POST")
  end

  # Executes a request simulating PUT HTTP method and set/volley the response
  def put(action, parameters = nil, session = nil, flash = nil)
    process_action(action, parameters, session, flash, "PUT")
  end

  # Executes a request simulating DELETE HTTP method and set/volley the response
  def delete(action, parameters = nil, session = nil, flash = nil)
    process_action(action, parameters, session, flash, "DELETE")
  end

  private

  def process_action(action, parameters = nil, session = nil, flash = nil, method = "GET")
    parameters ||= {}
    process(action, parameters.merge!(:use_route => :my_engine), session, flash, method)
  end
end

RSpec.configure do |c|
  c.include ControllerHacks, :type => :controller
end

Answer 3

Use the rspec-rails routes directive:

describe MyEngine::WidgetsController do
  routes { MyEngine::Engine.routes }

  # Specs can use the engine's routes & named URL helpers
  # without any other special code.
end

– RSpec Rails 2.14 official docs.

Answer 4

Solution for a problem when you don't have or cannot use isolate_namespace:

module Posts
  class Engine < Rails::Engine
  end
end

In controller specs, to fix routes:

get :show, {:id => 1, :use_route => :posts_engine}   

Rails adds _engine to your app routes if you don't use isolate_namespace.

Answer 5

I'm developing a gem for my company that provides an API for the applications we're running. We're using Rails 3.0.9 still, with latest Rspec-Rails (2.10.1). I was having a similar issue where I had defined routes like so in my Rails engine gem.

match '/companyname/api_name' => 'CompanyName/ApiName/ControllerName#apimethod'

I was getting an error like

ActionController::RoutingError:
 No route matches {:controller=>"company_name/api_name/controller_name", :action=>"apimethod"}

It turns out I just needed to redefine my route in underscore case so that RSpec could match it.

match '/companyname/api_name' => 'company_name/api_name/controller_name#apimethod'

I guess Rspec controller tests use a reverse lookup based on underscore case, whereas Rails will setup and interpret the route if you define it in camelcase or underscore case.

Answer 6

Based on this answer I chose the following solution:

#spec/spec_helper.rb
RSpec.configure do |config|
 # other code
 config.before(:each) { @routes = UserManager::Engine.routes }
end

The additional benefit is, that you don't need to have the before(:each) block in every controller-spec.