Here are the simple (?) steps to get Rails 3 running with the above technologies.

Install Rails

You know, this is pretty obvious, but before you get into any other hoo ha you are going to have to get a version of Rails installed into your system gems so that you will have access to the rails command.

So:

$ gem install rails --version "3.0.0.beta3"
Successfully installed i18n-0.3.7
Successfully installed tzinfo-0.3.20
Successfully installed builder-2.1.2
Successfully installed memcache-client-1.8.3
Successfully installed activesupport-3.0.0.beta3
Successfully installed activemodel-3.0.0.beta3
....

Should do the trick.

Setup the Rails app

Now we have Rails install our app using the standard rails g command.

$ rails my_app -JT
     create  
     create  README
     create  .gitignore
     create  Rakefile
     create  config.ru
     create  Gemfile
     ....

The -J parameter, tells Rails not to install the Prototype Javascript libraries. The -T tells it to skip generating the Test::Unit files, together they order Cheese Royals

Setting up RVM

Now change into the my_app directory and add the line rvm ruby-1.8.7@my_app to the .rvmrc file

$ echo "rvm ruby-1.8.7@my_app" > .rvmrc

This will make a clean gemset for our Rails app to play in.

But we need to create the gemset first:

$ rvm gemset create 'my_app'
Gemset 'my_app' created.

Nice.

Now whenever we cd into the my_app directory, RVM will auto detect the .rvmrc file and switch our gemset to the my_app Gemset.

Or we can do it manually:

$ rvm ruby-1.8.7@my_app
$ gem list

*** LOCAL GEMS ***

rake (0.8.7)

Awesome.

House Keeping

$ cd my_app/
$ rm public/index.html
$ rm public/images/rails.png 

Notice I deleted the index.html and rails.png above. You don’t have to do this right now, if you want to see the nice happy message telling you that daisies are going to bloom and butterflies are fluttering about because your Rails App is now working, please don’t remove it yet, wait and fire up your rails app with rails s and browse to http://127.0.0.1:3000 and bask in your RailsFuNess…

But for the rest of us, nuke it.

Getting jQuery installed

Next, we need to install jQuery. Just go to the website and download it and place it into your javascripts directory. For cut and fiends out there, this curl command should handle it as well:

$ mkdir public/javascripts/jquery
$ curl http://code.jquery.com/jquery-1.4.2.min.js > public/javascripts/jquery/jquery-1.4.2.min.js

Note I have put this into a jQuery folder. I have done this so that the javascript_include_tag :all command I will use further down does not pickup the jQuery source files.

Getting the Rails jQuery Driver

Now that we have destroyed prototype, we need to replace it with jQuery, two steps to this.

First, download the jQuery driver and over write your rails.js file that lives in public/javascripts/, I usually do this by going to the Rails jQuery-UJS page and clicking raw and cut and pasting it into the public/javascripts/rails.js file. Feel free to use a submodule if you wish, or

$ curl http://github.com/rails/jquery-ujs/raw/59dd91d945570391f905b1e40444e5921dbc2b8f/src/rails.js > public/javascripts/rails.js

Will do it as well… note, this will most likely not be the most recent version in the future. To get the latest, go to the Rails jQuery-UJS page and click on the RAW link to the right of the source code div.

Wiring up jQuery and the Rails driver

Now that we have jQuery and the Rails jQuery UJS drivers installed, we need to wire them up to the app, so open up app/views/layouts/application.html.erb make it look like the following:

<!DOCTYPE html>
<html>
<head>
  <title>MyApp</title>
  <%= stylesheet_link_tag :all %>
  <%= csrf_meta_tag %>
</head>
<body>

<%= yield %>

<%= javascript_include_tag 'jquery/jquery-1.4.2.min' %>
<%= javascript_include_tag :all, :cache => true %>
</body>
</html>

OK, couple of things here. Firstly, we remove the javascript_include_tag :all from the header. Then we put the two tags at the bottom of the document.

Why do we separate out the jquery/jquery-1.4.2.min from the javascript_include_tag :all line? This is because the :all directive will just grab all the javascript files in the order it finds them and bundle them all together, which means that your javascript files, may be trying to init javascript classes from your jQuery library that do not exist yet.

So we get around this by loading jQuery first.

OK. So that is jQuery sorted, now onto the specifications side.

Installing RSpec & Friends

Best way to go about this, is to modify your Gemfile and make it look something like this:

source 'http://rubygems.org'

## Bundle edge rails:
gem "rails",  :git => "git://github.com/rails/rails.git"
gem "sqlite3-ruby"

group :test do
  gem "rspec"
  gem "rspec-rails",      ">= 2.0.0.beta"
  gem "machinist",        :git => "git://github.com/notahat/machinist.git"
  gem "faker"
  gem "ZenTest"
  gem "autotest"
  gem "autotest-rails"
  gem "cucumber",         :git => "git://github.com/aslakhellesoy/cucumber.git"
  gem "database_cleaner", :git => 'git://github.com/bmabey/database_cleaner.git'
  gem "cucumber-rails",   :git => "git://github.com/aslakhellesoy/cucumber-rails.git"
  gem "capybara"
  gem "capybara-envjs"
  gem "launchy"
  gem "ruby-debug"
end

This is going to install everything you need to get RSpec, Cucumber, Machinist, autotest and even throwing in the Ruby Debugger at the bottom.

Save this, and then we need to install it. But remember, we are on a clean gemset, so we need to install bundler first:

 $ gem install bundler
Successfully installed bundler-0.9.25
1 gem installed
Installing ri documentation for bundler-0.9.25...
Installing RDoc documentation for bundler-0.9.25...

mikel@baci.lindsaar.net ~/Code/my_app
 $ gem list

*** LOCAL GEMS ***

bundler (0.9.25)
rake (0.8.7)

Good to go, so now we are just a bundle install away from launching:

 $ bundle install
Fetching source index from http://rubygems.org/
Using rake (0.8.7) from system gems 
Installing abstract (1.0.0) from .gem files at /Users/mikel/.rvm/gems/ruby-1.8.7-p249@my_app/cache 
...

And we are away!

Initializing RSpec and Cucumber

Now that we have all our dependencies done, we need to tell RSpec and Cucumber to get a move on:

$ rails g rspec:install
      exist  lib
     create  lib/tasks/rspec.rake
      exist  config/initializers
     create  config/initializers/rspec_generator.rb
     create  spec
     create  spec/spec_helper.rb
     create  autotest
     create  autotest/discover.rb

And then for cucumber, we will use capybara (because we installed it in the Gemfile above) and pass —rspec because I like being complete!

$ rails g cucumber:skeleton --capybara --rspec
     create  config/cucumber.yml
     create  script/cucumber
      chmod  script/cucumber
     create  features/step_definitions
     create  features/step_definitions/web_steps.rb
     create  features/support
     create  features/support/paths.rb
     create  features/support/env.rb
      exist  lib/tasks
     create  lib/tasks/cucumber.rake
       gsub  config/database.yml
       gsub  config/database.yml
      force  config/database.yml

OK good.. so that is our skeleton app.

One last thing, we are using Rails with sqlite, so it will expect our databases to exist before it will run any tests, so let’s make them:

$ rake db:create

Getting our first feature to run

Now that we have our app installed and everything wired up, we should be able to get an initial feature working, so go ahead and make a features/the_home_page.feature file, and whack something like this in it:

Feature: Manage app_should_boots
  In order to see what my app is about
  a user
  wants to be able to land on a home page
  
  Scenario: Visiting the site for the first time
    Given I am on the home page
    Then I should see "Welcome" within "h1"

This should fail:

Using the default profile...
.F

(::) failed steps (::)

scope '//h1' not found on page (Capybara::ElementNotFound)
./features/step_definitions/web_steps.rb:14:in `with_scope'
./features/step_definitions/web_steps.rb:108:in `/^(?:|I )should see "([^\"]*)"(?: within "([^\"]*)")?$/'
features/the_home_page.feature:8:in `Then I should see "Welcome" within "h1"'

Failing Scenarios:
cucumber features/the_home_page.feature:6 # Scenario: Visiting the site for the first time

Which is saying that the default rails “Not Found” page does not have “Welcome” within a “h1” tag… which I guess is true!

Lets fix this:

First we’ll generate the welcome controller:

$ rails g controller welcome
     create  app/controllers/welcome_controller.rb
     invoke  erb
     create    app/views/welcome
     invoke  rspec
     create    spec/controllers/welcome_controller_spec.rb
     create    spec/views/welcome
     invoke  helper
     create    app/helpers/welcome_helper.rb
     invoke    rspec

Then we’ll edit the config/routes.rb file to wire up the root url to the welcome controllers index action:

MyApp::Application.routes.draw do |map|
  root :to => "welcome#index"
end

Note, if you haven’t already deleted the public/index.html file, now is a good time to do it!

Now we make an app/views/welcome/index.html.erb file and put in it our welcome message:

<h1>Welcome</h1>

And now we will re-run our cucumber feature and all should be good:

 $ rake cucumber
Using the default profile...
..

1 scenario (1 passed)
2 steps (2 passed)
0m0.214s

Cool! We are now on the Rails with Cucumber and everything else that is good in the world.

Enjoy!

blogLater

Mikel