Ruby-on-rails – How to test routes in a Rails 3.1 mountable engine

rspec2ruby-on-railsruby-on-rails-3

I am trying to write some routing specs for a mountable rails 3.1 engine. I have working model and controller specs, but I cannot figure out how to specify routes.

For a sample engine, 'testy', every approach I try ends with the same error:

 ActionController::RoutingError:
   No route matches "/testy"

I've tried both Rspec and Test::Unit syntax (spec/routing/index_routing_spec.rb):

describe "test controller routing" do
  it "Routs the root to the test controller's index action" do
    { :get => '/testy/' }.should route_to(:controller => 'test', :action => 'index')
  end

  it "tries the same thing using Test::Unit syntax" do
    assert_routing({:method => :get, :path => '/testy/', :use_route => :testy}, {:controller => 'test', :action => 'index'})
  end
end

I've laid out the routes correctly (config/routes.rb):

Testy::Engine.routes.draw do
  root :to => 'test#index'
end

And mounted them in the dummy app (spec/dummy/config/routes.rb):

Rails.application.routes.draw do
  mount Testy::Engine => "/testy"
end

And running rails server and requesting http://localhost:3000/testy/ works just fine.

Am I missing anything obvious, or is this just not properly baked into the framework yet?

Update: As @andrerobot points out, the rspec folks have fixed this issue in version 2.14, so I've changed my accepted answer accordingly.

Best Answer

Since RSpec 2.14 you can use the following:

describe "test controller routing" do
  routes { Testy::Engine.routes }
  # ...
end

Source: https://github.com/rspec/rspec-rails/pull/668

Related Solutions

Ruby-on-rails – Rails: How to rename a database column in a Ruby on Rails migration

rename_column :table, :old_column, :new_column

You'll probably want to create a separate migration to do this. (Rename FixColumnName as you will.):

script/generate migration FixColumnName
# creates  db/migrate/xxxxxxxxxx_fix_column_name.rb

Then edit the migration to do your will:

# db/migrate/xxxxxxxxxx_fix_column_name.rb
class FixColumnName < ActiveRecord::Migration
  def self.up
    rename_column :table_name, :old_column, :new_column
  end

  def self.down
    # rename back if you need or do something else or do nothing
  end
end

For Rails 3.1 use:

While, the up and down methods still apply, Rails 3.1 receives a change method that "knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method".

See "Active Record Migrations" for more information.

rails g migration FixColumnName

class FixColumnName < ActiveRecord::Migration
  def change
    rename_column :table_name, :old_column, :new_column
  end
end

If you happen to have a whole bunch of columns to rename, or something that would have required repeating the table name over and over again:

rename_column :table_name, :old_column1, :new_column1
rename_column :table_name, :old_column2, :new_column2
...

You could use change_table to keep things a little neater:

class FixColumnNames < ActiveRecord::Migration
  def change
    change_table :table_name do |t|
      t.rename :old_column1, :new_column1
      t.rename :old_column2, :new_column2
      ...
    end
  end
end

Then just db:migrate as usual or however you go about your business.

For Rails 4:

While creating a Migration for renaming a column, Rails 4 generates a change method instead of up and down as mentioned in the above section. The generated change method is:

$ > rails g migration ChangeColumnName

which will create a migration file similar to:

class ChangeColumnName < ActiveRecord::Migration
  def change
    rename_column :table_name, :old_column, :new_column
  end
end

How to write a Rails 3.1 engine controller test in rspec

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

Best Answer

Related Solutions

Ruby-on-rails – Rails: How to rename a database column in a Ruby on Rails migration

How to write a Rails 3.1 engine controller test in rspec

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