Fear no more. A pastie is at hand.

Here’s how to install it:

In your `.bash_profile` add the following:

Thanks

@dwaite and others for `$@` instead of `$0 $1 …`.

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It irked me a little that I could develop on one stack (OS X, Rubinius, Sqlite3), run continuous integration (CI) on another stack (Ubuntu, Ruby 1.8.7, Postgresql), and deploy into another stack (Gentoo, Ruby 1.9.2, MySQL). I think what irks and worries me is that there are three sets of differences to be aware of. A bug in production? Was it a missing test scenario or one of the many differences between production and CI environments?

So I think I have two solutions.

First, use a VM that matches the production environment. Each different production environment would mean another VM. If you are managing your own production environment, then all you need is the tools (described in this article) to recreate your production environment in a VM.

Second, use a clone of your production environment. That is, if you deploy to Engine Yard AppCloud then run CI in Engine Yard AppCloud; if you deploy to a single Ubuntu instance on Slicehost, the have another matching Ubuntu instance on Slicehost.

I’ll write about the first solution – using VMs – here, and I’ll write on the Engine Yard Blog about the solution for Engine Yard AppCloud customers. For AppCloud users life will be even easier because there are zero setup steps to ensure you have consistent environments. It’s been one of my favorite projects in the two months since I arrived at Engine Yard.

I’ll also introduce a CLI for talking to Hudson – one that assumes you are working on Ruby/Rails projects – and makes it really easy to get up and running with a server, your Rails/Ruby projects, and any VMs you need (optional for Hudson, but they are the point of my line of thinking).

And I’ll introduce Vagrant, a CLI for creating/managing/destroying VMs.

Oh, and I’ll introduce Hudson CI.

Ok, let’s fix all our CI problems in one go…

Hudson CI

I needed a CI tool to allow tests to run inside VMs or on remote servers/VMs. Back in May I found and fell in love with Hudson CI. Fortunately it had support for “slaves”, and a way for CI jobs (your applications or rubygems) to select which slaves can be used. Hudson is also great because it is easy to try out (one click to install and launch), easy to configure, and has 350+ plugins.

What is Hudson?

CLI for Hudson

Charles Lowell’s hudson.rb project is a CLI for launching Hudson (it’s bundled inside the gem), and a set of CLI tasks to add/remove projects (jobs), add slaves, trigger builds and more.

gem install hudson

You can launch Hudson via:

hudson server  # Default: --port 3001
open http://localhost:3001

It currently assumes you are working on Ruby projects, using bundler, and attempts to create a useful set of default steps for your CI jobs.

cd /some/rails3/app
hudson create . --host localhost --port 3001 --template rails3

Hudson CI will automatically start running steps to install your application’s gems, database, and run your tests. When it does it on your local machine it’s not that impressive. When it happens on a fresh VM or slave node and you didn’t have to do anything to set it up, it’s awesome.

V is for Vagrant, VirtualBox and all things VM

If you can script it, then you can automate it. Fortunately, as a virtual machine VirtualBox is both scriptable and FREE! Secondly, if you have a VM, you’ll need to script its setup/provisioning; so fortunately there exists chef and puppet, amongst others.

Thirdly, if you are really really really lazy, like me, you will want Vagrant. Created by Mitchell Hashimoto and John Bender, Vagrant is a tool for building and distributing virtualized development environments. Everyone in your team have their own OS/configuration? Got Windows users on your team? Use Vagrant.

Once you have VirtualBox installed, getting any of your projects live within a VM is trival:

gem install vagrant
vagrant box add base http://files.vagrantup.com/lucid32.box
vagrant init
vagrant up
vagrant ssh
$ cd /vagrant/
$ ls -al

You will now see the contents of your project folder, but from within the VM instance! They are linked – a change to either is automatically reflected inside and outside of the VM.

In this example, the Guest OS being downloaded and installed into VirtualBox (note: without any GUI) is Ubuntu Lucid, but you could use any VirtualBox packaged unix system.

For wonderful guided tour of Vagrant see the Getting Started video.

Vagrant – Getting Started from Mitchell Hashimoto on Vimeo.

Hudson CI + Vagrant = Perfect CI

Whether you choose to use VMs for a production-like development environment (a good idea for anyone, a wonderful idea for Windows developers who are very far removed from their production experience), it is a very good idea to have a CI environment as similar to your production environment as possible. Here, we want a VM instance with all the components/utilities/rubies set up that you have in production.

I have created an example Rails application that is setup to use Vagrant for a CI slave VM.

See the README for complete instructions. See the Vagrantfile and the cookbooks folder for the configuration and provisioning recipes.

Once you have the VM instantiated, you add it to your Hudson CI master (either the localhost one above or your remotely hosted server) with the CLI:

hudson add_node localhost --name "VM" --label railsapp-vagrant ...

(See the example Rails application for the other flags I used to get this working). It is now available to all Hudson jobs; but has a label “railsapp-vagrant” to allow jobs (Hudson’s name for a project) to specify that slave node specifically.

To add the Rails application to Hudson CI, and force it to run the tests in this VM:

hudson create . --template rails3 --assigned-node railsapp-vagrant

If you visit the Hudson master (at http://localhost:3010 in the example) you will see the job automatically running (“building”) within your VM. It will use bundler to install the gems, and run all the tests.

That’s it?

I know, CI is historically a pain in the arse. When CruiseControl was the only CI kid-on-the-block, it was standard for people to respond “4 days” to the question “How long does it take to get set up?”

It can now be really easy.

More importantly than being easy, you are running an application’s tests within an isolated VM that you can design to match your production environment.

I think there can be a good future for CI and Rails applications. Thoughts on this solution?

Thanks

Some of the technology in this article is old, other bits are very new, but for all of it I thank all the creators and contributors. Hudson CI was created by Kohsuke Kawaguchi during his days at Sun. He is now offering Hudson support services via his company InfraDNA.

The Hudson.rb project was created by Charles Lowell to bundle the Hudson CI and some common useful plugins for Ruby/Rails projects. He came all the way to Gothenburg, Sweden for NordicRuby conference (great conference by the way!) I fell in love with Hudson and started helping Charles on Hudson.rb.

Thanks also to both Kohsuke and Charles for starting work on a JRuby plugin for Hudson CI, and writing up a progress report.

Thanks to everyone who agrees that Hudson CI is awesome.

Thanks to Mitchell Hashimoto and John Bender for creating Vagrant. It is an incredible tool for developing within a VM (on OS X or Windows).

Finally, thanks to Bo Jeanes who helped on the Engine Yard AppCloud version of this project. Coming soon!

RubyConf & RubyBayou

If you’re in New Orleans this week for RubyConf, I’ll be at the local Ruby group RubyBayou talking about Hudson CI, Vagrant, and AppCloud on Thursday night. There’s a happy hour from 5pm till the 7pm start.

Location: LaunchPad NOLA, 643 Magazine St, New Orleans, LA 70130

Come and let me convince you about the wonders of Hudson CI and having a CI test environment that matches your production env. You know you want to be convinced. It’s good for you, like fruit.

Don’t forget Chuck Norris

Always remember to install the Chuck Norris plugin for Hudson, and enable it for each job. Don’t forget Chuck Norris.

So I added the same thing to my Ruby.tmbundle. Install this, save a dodgy Ruby file and you’ll now see something like:

Rubinius superpowers

Do you think the following syntax error tooltip is more useful?

Yes it lovely, and the new Ruby.tmbundle will automatically do this if it can find rbx in your TextMate’s $PATH. Yeah yeah.

If you have Homebrew installed:

brew install rubinius

Then in TextMate, add your homebrew bin folder to the $PATH.

• Go to TextMate’s Preferences (Cmd+,)
• Go to “Advanced”, then “Shell Variables”
• Edit the PATH variable, and add “:/path/to/homebrew/bin”

For example, if you have homebrew installed in ~/.homebrew then you might add :/Users/drnic/.homebrew/bin

. My complete $PATH in TextMate is:

/usr/bin:/bin:/usr/sbin:/sbin:/opt/local/bin:/usr/local/bin/:/Users/drnic/.homebrew/bin

Save a dodgy Ruby file and see the beautifully helpful syntax message.

Install Ruby.tmbundle

To install via Git:

mkdir -p ~/Library/Application\ Support/TextMate/Bundles
cd ~/Library/Application\ Support/TextMate/Bundles
git clone git://github.com/drnic/ruby-tmbundle.git "Ruby.tmbundle"
osascript -e 'tell app "TextMate" to reload bundles'

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What is CoffeeScript?

Imagine all the syntactical delights of Ruby and Haml for your JavaScript. You write in a nice language, but get normal JavaScript at runtime. All whilst having full access to 3rd-party JavaScript libraries (jQuery, PrototypeJS), debugging support (it becomes pure, readable JavaScript), existing support from test suites (it’s normal JavaScript) and growing support from various text editors (TextMate, Vim, Emacs).

What simple delights?

No trailing semi-colons. No { some_code() } function/closure brackets. String interpolation. Multi-line strings. Explicit class syntax. Array slicing. An existential ? operator.

Scroll down the home page for awesome example after example.

These aren’t library extensions. This is clean, purposeful syntax.

You can play with the joyful syntax of CoffeeScript on the website. After reading the basic examples on the CoffeeScript home page, press “TRY COFFEESCRIPT” in the header menu.

As you play with the syntax, the equivalent JavaScript is printed on the right hand side (see image above).

How nice is that syntax? Very.

Installing CoffeeScript

1. Install NodeJS
2. Install CoffeeScript

For NodeJS (get latest release URL; using 0.1.31 as 0.1.32 doesn’t unpack for me):

cd /usr/local/src
wget http://nodejs.org/dist/node-v0.1.31.tar.gz
tar xfv node-v0.1.31.tar.gz
cd node-v0.1.31
./configure
make
sudo make install

For CoffeeScript (get latest release URL):

cd /usr/local/src
wget http://github.com/jashkenas/coffee-script/tarball/0.5.5
tar xfv jashkenas-coffee-script-bcf7b3f.tar.gz
cd jashkenas-coffee-script-bcf7b3f
sudo bin/cake install

Now test that everything is in place:

$ coffee --version
CoffeeScript version 0.5.5
$ coffee -e "sys: require 'sys'; sys.puts 'hello world\n'"
hello world

Phew!

Note, in the command-line/on the server, you are using the NodeJS JavaScript environment. It supports the CommonJS API for loading modules (normal JavaScript: var sys = require('sys')).

Um, but how do I use it in my web app?

Your application source code will have *.coffee files containing your sexy, short CoffeeScript. But at runtime, the browser needs the generated JavaScript.

I’ve been using the Jonas Nicklas’ bistro_car gem:

gem install bistro_car
mkdir -p app/scripts

In your Rails config/environment.rb file, add:

config.gem 'bistro_car'

And in your layouts, such as app/views/layouts/application.html.erb add to the <head> or the bottom:

<%= coffee_script_bundle %>

Now you’re good to go. Add your CoffeeScript files in app/scripts/*.coffee and they will be automatically available as JavaScript.

WARNING: Check your version of CoffeeScript

Check that this hasn’t happened:

$ coffee --version
CoffeeScript version 0.3.2
$ which coffee
/usr/bin/coffee

Arrgh, we should be using /usr/local/bin/coffee. bistro_car currently installs the old rubygem-based version of coffee-script; and you might be unlucky to have your $PATH find the wrong one first.

Either delete it (sudo rm /usr/bin/coffee and restart your shell) or make sure /usr/local/bin is earlier in your $PATH than /usr/bin, where RubyGems installed the old, unnecessary version of coffee command.

Let’s drink the CoffeeScript

Create a file app/scripts/application.coffee with contents:

powers: [1,2,3,4].map (i) -> i * i
alert powers

Load up a view in a browser and see [1,4,9,16]. You win! Throw in some jQuery/PrototypeJS/whatever. Beautiful.

View the source of the page, navigate to public/javascripts/bundle/default.js and you’ll see the generated source:

(function(){
  var powers;
  powers = [1, 2, 3, 4].map(function(i) {
    return i * i;
  });
  alert(powers);
})();

The problem: Heroku doesn’t have CoffeeScript installed

Heroku is a great place to host apps. Though it doesn’t have CoffeeScript installed so it cannot dynamically convert the *.coffee files into JavaScript.

If you want to use Heroku I guess we need to perform the conversion locally and deploy it.

But. In development and integration testing I want bistro_car’s dynamically generated default.js. In production, I need a cached version.

In application.html.haml I use (I can’t keep pretending I use erb):

- if Rails.env.production?
  = javascript_include_tag "coffeescripts"
- else
  = coffee_script_bundle

Now we’re just left with the hassle of automatically generating public/javascripts/coffeescripts.js.

First, a rake task. Second, a git pre-commit hook.

Create lib/tasks/bistro_car.rake:

desc "Generate the cached bundle/default.js file from app/scripts/*.coffee files"
task :bistro_car => :environment do
  path = "public/javascripts/coffeescripts.js"
  puts "Building *.coffee -> #{path}"
  File.open(path, "w") { |file| file << BistroCar::Bundle.new('default').to_javascript }
end

file "public/javascripts/coffeescripts.js" => Dir[File.join(Rails.root, 'app/scripts/*.coffee')] do |t|
  Rake::Task["bistro_car"].invoke
end

Now you can create coffeescripts.js and add it to the repo with:

rake public/javascripts/coffeescripts.js
git add public/javascripts/coffeescripts.js
git commit -m "Initial bundled coffeescripts file"

Now create .git/hooks/pre-commit:

#!/bin/sh

exec rake public/javascripts/coffeescripts.js

And make it executable (and git commit will invoke it automatically):

chmod +x .git/hooks/pre-commit

Phew.

Now, whenever you change a *.coffee script and you are about to commit it, the cached-production-only coffeescripts.js is automatically updated and included in the same commit.

Seems like a clean hack.

Summary

Why not make a library to do this? Well I’m hoping there is a better, cleaner way. Perhaps bistro_car can include a rails generator to package these bits and pieces itself, if my approach happens to be the best way.

Nonetheless, let history record that CoffeeScript is very cool though in the world of Heroku living with it is non-trivial at the moment.

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Ever used a rubygem, found a bug, and just wanted to quickly bust out the big guns and fix it quickly?

The gem command doesn’t come packed with a way to find the original source repository for a gem. At best, most gems at least come bundled with the complete source, tests and documentation. Some gems don’t. Fair enough, since having access to the complete source via the gem still doesn’t allow you to fix a bug and share it with the world.

For that you access to the repo, a quick way to fork it, and a post-github way to share a gem version from yours truly.

The github gem and gemcutter are the modern day tools of master hackermanship.

Instant forking fun

Let’s say you find a bug in a gem, say rails, and you want to go to town on its source.

You know the gem is called rails but you’ve no idea what the github repo is called. Never fear.

$ gem sources -a http://gemcutter.org
$ sudo gem install github
$ gh clone --search rails
Select a repository to clone:
1.  rails/rails                         # Ruby on Rails
2.  technoweenie/restful-authentication # Generates common user ...
3.  justinfrench/formtastic             # A Rails form builder plugin ...
?

Press 1 and you’ll get a clone of rails/rails.

Alternately, if you want a fork or you know the exact user/repo already:

$ gh clone rails/rails

Now, fork your own version:

$ cd rails
$ gh fork

You now have your own fork. The origin remote also now points to your fork rather than the rails/rails repository:

$ git remote show origin
* remote origin
  Fetch URL: git@github.com:drnic/rails.git
  Push  URL: git@github.com:drnic/rails.git

So, make your changes, push them. Send a pull request or github issue or lighthouse ticket or what have you.

Want to get to the github project home page for your fork?

$ gh home

Instant gem sharing

Let’s say you patched the rails gem itself but you want to share your changes via your own gem.

In the olden days, github did this for you. Now you use gemcutter, and a little manual effort to do your own renaming.

First, install the gems locally, use them, and make sure all is good.

For rails, you install the edge gems (3.0.pre) with:

$ rake install

You can’t see ‘rake install’ in the rake -T list (hence my patch), but I think the following expression displays all tasks regardless if they have a description or not:

$ rake -P | grep "^r"

Rails is composed of several gems, unlike most projects that are distributed as a single gem. Here we want to share our commit within a new drnic-rails gem, but not touch the others.

Edit the railties/rails.gemspec file from:

Gem::Specification.new do |s|
  s.platform = Gem::Platform::RUBY
  s.name = 'rails'
  s.version = '3.0.pre'
...

and give your personal gem a new name:

Gem::Specification.new do |s|
  s.platform = Gem::Platform::RUBY
  s.name = 'drnic-rails'
  s.version = '3.0.pre'

To build and distribute the new gem:

$ gem build railties/rails.gemspec
$ sudo gem install gemcutter
$ gem push drnic-rails-3.0.pre.gem
  Pushing gem to Gemcutter...
  Successfully registered gem: drnic-rails (3.0.pre)

Follow any first-time gemcutter instructions and SUCCESS! Now I have my own drnic-rails gem.

Summary

To find, clone, and fork any rubygem that is hosted on github:

$ sudo gem install drnic-github
$ gh clone --search rails
$ gh fork

To personalise the gem and share it on gemcutter:

> edit the project.gemspec to have a unique name, e.g. yourname-project
$ gem build project.gemspec
$ sudo gem install gemcutter
$ gem push yourname-project-1.0.0.gem

I think this makes it much easier, faster and more fun to hack other people’s stuff.

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This article is out of date in some aspects. See comments, and perhaps this summary of reading materials about Rails 3.

Today I had my first look at rails 3.0.pre and below are the sequence of steps I had to take to create a rails 3.0.pre application, and get it’s generators to work.

Why was I looking at the top-secret, yet open-source Rails 3.0? Their generators are being migrated over to Thor and I wanted to see them in action. I was thinking I might migrate newgem to use Thor too.

Here’s a quick poke around of getting started and interesting things I found. Any hiccups and workarounds are meant as a guide to pre-pre-3.0 users/developers and not as a criticism of rails-core. Rails 3.0 is looking shiny and awesome.

NOTE: Since this is a “how to install and use” rails 3.0 edge, which is still in heavy development, this set of instructions might break. Let’s hope not.

Getting Started

As of today, you cannot install 3.0.pre from rubygems [1]. So, let’s install them from source. Which is handy, you might like to patch something.

$ cd ~/gems
$ git clone git://github.com/rails/rails.git
use_ruby_191 *

[*] If you are on OS X Snow Leopard I think you can ignore this. Otherwise, since you don’t have the 3.0.pre gems installed, you’re about to hit bump #1. Ruby 1.8.6 doesn’t have Symbol#to_proc but it’s required to create a rails app. This means you’ll need to be able to switch to another version of ruby temporarily if you’re on ruby 1.8.6 [2].

cd ~/Sites
ruby ~/gems/rails/railties/bin/rails

Oooh, look at all the new options! Some new ones are:

-F, [--freeze]             # Freeze Rails in vendor/rails from the gems
-O, [--skip-activerecord]  # Skip ActiveRecord files
-T, [--skip-testunit]      # Skip TestUnit files
-J, [--skip-prototype]     # Skip Prototype files

The -D, --with-dispatchers flags have been removed. --freeze isn’t new, but -F is.

So, to create an app, I dutifully used:

ruby ~/gems/rails/railties/bin/rails edgerailsapp -F

BAM! Fail. The -F option to freeze/vendor rails fails without the gems installed. So don’t use it.

ruby ~/gems/rails/railties/bin/rails edgerailsapp
ln -s ~/gems/rails vendor/rails

If you’re on Windows without the symlink command ln, then copy the downloaded rails source into vendor/rails.

Fetch Rails’ dependencies

Rails 3.0 source uses the new bundler project to describe its own dependencies. From Nick Quaranto’s article on bundler, get the latest:

cd ~/gems
git clone git://github.com/wycats/bundler
cd bundler
sudo rake install

Now, back in your app, you need to install some rails dependencies here too. It’s a good chance to see how you’ll bundle gem dependencies in the future.

$ cd ~/Sites/edgerailsapp

Change the Gemfile in your project to the following:

gem "rack",          "1.0.1"
gem "rack-mount",    :git => "git://github.com/rails/rack-mount.git"
gem "rack-test",     "~> 0.5.0"
gem "erubis",        "~> 2.6.0"
gem "arel",          :git => "git://github.com/rails/arel.git"
gem "sqlite3-ruby"
gem "rails", "3.0.pre", :git => "git://github.com/rails/rails.git"

Welcome to the future of gem dependencies for rails apps. Ultimately you won’t need to manually add these lines yourself. When rails is distributed as gems it will automatically install these for you, I assume/hope/guess. But for today, you seem to need them.

Now locally (within your app) install these gems:

$ gem bundle

If you get “can’t convert Pathname into String” then revert to ruby 1.8.X and reinstall bundler into your 1.8 gem cache.

Phew. Ooh, my god. Phew. Only now will script/generate work.

$ script/generate

For me, this outputs:

Please select a generator.
Builtin: app, controller, generator, helper, integration_test, mailer, metal, migration, model, model_subclass, observer, performance_test, plugin, resource, scaffold, scaffold_controller, session_migration, stylesheets.
Others: app_layout:app_layout, check_migration_version:check_migration_version, home_route:home_route.

The “Builtin” generators are the latest and greatest in Thor technology. Rails 3.0 no longer uses its own generator but is built upon Thor.

For example, our old favourite model generator works thusly:

$ script/generate model Post title:string --no-fixture
    invoke  active_record
    create    db/migrate/20091103030824_create_posts.rb
    create    app/models/post.rb
    invoke    test_unit
    create      test/unit/post_test.rb

Interestingly, --no-fixture isn’t mentioned in the usage information for script/generate model. It mentions the --fixture flag, but I had to guess that --no-fixture was also supported.

Hmm, I want to use rspec. So, let’s destroy these files:

$ script/destroy model Post title:string
      invoke  active_record
.../vendor/gems/dirs/rails/railties/lib/rails/generators/active_record.rb:14:in
  `next_migration_number': uninitialized constant ActiveRecord::Base (NameError)

Oh well.

What if I wanted to run rspec and cucumber generators, for example, against an edge rails app?

Rails 2 generators

The “Others” generators are my own local generators from ~/.rails/generators. Amusingly, instead of app_layout it is called app_layout:app_layout. Not surprisingly at all, if I try to run the rails 2 generator it fails:

$ script/generate app_layout:app_layout
[WARNING] Could not load generator at "/Users/drnic/.rails/generators/app_layout/app_layout_generator.rb". Error: uninitialized constant Rails::Generator
Could not find generator app_layout:app_layout.

Poop.

Note, I have rspec, rspec-rails and cucumber gems installed locally but I cannot see their rails generators above. Rails 3 doesn’t look for generators in the same way and old Rails 2 generators don’t work anymore.

That’s the news: every rails 2 generator is broken.

When I start to migrate some of mine I’ll post about it. In the meantime, José Valim has written some introduction thoughts on using Thor as a generator.

You can also probably learn about how to write rails 3.0 generators by looking at the source code for the new generators like rails, model (see main and test_unit), and scaffold/resource.

Finally, José Valim has a sample Rails 3 app with some vendored generators in it.

These are the things I’m researching now.

Summary

This article is long, mostly because rails 3.0.pre hasn’t been released as a set of RubyGems. If it had, then all the dependencies would be installed automatically.

It also introduces gem/plugin writers to the first upgrade issue: your current generators are neither discovered nor work by a rails 3.0 app. We’re all clever cookies, so here’s hoping we can figure out the upgrade path and that it’s simple enough to not be the topic of Dan Brown’s next book.

Footnotes

[1] Two portions of rails 3.0.pre are available as pre-release gems: activesupport (which is now very modularised and only loads up the parts that you require) and activemodel (which is shiny and new and hence completely safe for rails-core to release).

[2] There are two popular ways to have easy, non-intrusive access to alternate versions of ruby: rvm and ruby_switcher.sh.

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When I do online banking I need to select from a large list of other people’s bank accounts to which I might like to transfer money too. It is the massive drop down list that I must scroll through that I wish to raise issue with today. The problem of having to give other people money is probably a different discussion.

And take those time-zone selector drop down lists, for example, the massively long list rendered by Rails’ time_zone_select helper. Granted, I am thankful for you letting me choose my timezone in your web app. Though for those of us not living in the USA we must hunt for our closest city in the list. Dozens of locations, ordered by time zone and not the name of the city (see adjacent image). Unfortunately you can’t easily type a few letters of your current city to find it. Rather, you have to scroll. And if you live in the GMT+1000 time zone group (Eastern Australia), you have to scroll all the way to the bottom.

So I got to thinking I’d like a Greasemonkey (for Firefox) or GreaseKit (for Safari) script that automatically converted all ridiculously long HTML drop down lists into a sexy, autocompletion text field. You could then type in “bris” and be presented with “(GMT+1000) Brisbane”, or given the less amusing banking scenario then I could type “ATO” and get the bank account details for the Australian Tax Office.

I mean, how hard could it be?

This article is two things: an introduction to Ninja Search JS which gives a friendly ninja for every drop down field to solve the above problem. Mostly, the rest of this article shows how I used test-driven development tools and processes on a Greasemonkey script.

Introducing Ninja Search JS

Click the banner to learn about and install the awesome Ninja Search JS. It includes free ninjas.

Currently it is a script for Greasemonkey (FireFox) or GreaseKit (Safari). It could be dynamically installed as necessary via a bookmarklet. I just haven’t done that yet. It could also be a FireFox extension so it didn’t have to fetch remote CSS and JS assets each time.

Ninja Search JS uses liquidmetal and jquery-flexselect projects created by Ryan McGeary.

Most importantly of all, I think, is that I wrote it all using TDD. That is, tests first. I don’t think this is an erroneous statement given the relatively ridiculous, and unimportant nature of Ninja Search JS itself.

TDD for Greasemonkey scripts

I love the simple idea of Greasemonkey scripts: run a script on a subset of all websites you visit. You can’t easily do this on desktop apps, which is why web apps are so awesome – its just HTML inside your browser, and with Greasemoney or browser extensions you can hook into that HTML, add your own DOM, remove DOM, add events etc.

But what stops me writing more of them is that once you cobble together a script, you push it out into the wild and then bug reports start coming back. Or feature requests, preferably. I’d now have a code base without any test coverage, so each new change is likely to break something else. Its also difficult to isolate bugs across different browsers, or in different environments (running Ninja Search JS in a page that used prototypejs originally failed), without a test suite.

And the best way to get yourself a test suite is to write it before you write the code itself. I believe this to be true because I know it sucks writing tests after I’ve writing the code.

I mostly focused on unit testing this script rather than integration testing. With integration testing I’d need to install the script into Greasemonkey, then display some HTML, then run the tests. I’ve no idea how’d I’d do that.

But I do know how to unit test JavaScript, and if I can get good coverage of the core libraries, then I should be able to slap the Greasemonkey specific code on top and do manual QA testing after that. The Greasemonkey specific code shouldn’t ever change much (it just loads up CSS and more JS code dynamically) so I feel ok about this approach.

For this project I used Screw.Unit for the first time (via a modified version of the blue-ridge rails plugin) and it was pretty sweet. Especially being able to run single tests or groups of tests in isolation.

Project structure

All the JavaScript source – including dependent libraries such as jquery and jquery-flexselect – was put into the public folder. This is because I needed to be able to load the files into the browser without using file:// protocol (which was failing for me). So, I moved the entire project into my Sites folder, and added the project as a Passenger web app. I’m ahead of myself, but there is a reason I went with public for the JavaScript + assets folder.

In vendor/plugins, The blue-ridge rails plugin is a composite of several JavaScript libraries, including the test framework Screw.Unit, and a headless rake task to run all the tests without browser windows popping up everywhere. In my code base blue-ridge is slightly modified since my project doesn’t look like a rails app.

Our tests go in spec. In a Rails app using blue-ridge, they’d go in spec/javascripts, but since JavaScript is all we have in this project I’ve flattened the spec folder structure.

The website folder houses the github pages website (a git submodule to the gh-pages branch) and also the greasemonkey script and its runtime JavaScript, CSS, and ninja image assets.

A simple first test

For the Ninja Search JS I wanted to add the little ninja icon next to every <select> element on every page I ever visited. When the icon is clicked, it would convert the corresponding <select> element into a text field with fantastical autocompletion support.

For Screw.Unit, the first thing we need is a spec/ninja_search_spec.js file for the tests, and an HTML fixture file that will be loaded into the browser. The HTML file’s name must match to the corresponding test name, so it must be spec/fixtures/ninja_search.html.

For our first test we want the cute ninja icon to appear next to <select> drop downs.

require("spec_helper.js");
require("../public/ninja_search.js"); // relative to spec folder

Screw.Unit(function(){
  describe("inline activation button", function(){
    it("should display NinjaSearch image button", function(){
      var button = $('a.ninja_search_activation');
      expect(button.size()).to(be_gte, 1);
    });
  });
});

The Blue Ridge textmate bundle makes it really easy to create the describe (des) and it (it) blocks, and ex expands into a useful expects(...).to(matcher, ...) snippet.

The two ellipses are values that are compared by a matcher. Matchers are available via global names such as equals, be_gte (greater than or equal) etc. See the matchers.js file for the default available matchers.

The HTML fixture file is important in that it includes the sample HTML upon which the tests are executed.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">

<head>
  <title>Ninja Search | JavaScript Testing Results</title>
  <link rel="stylesheet" href="screw.css" type="text/css" charset="utf-8" />
  <script src="../../vendor/plugins/blue-ridge/lib/blue-ridge.js"></script>
</head>

<body>
  <div>
    <label for="person_user_time_zone_id">Main drop down for tests</label>
    <select name="person[user][time_zone_id]" id="person_user_time_zone_id" style="display: inline;">
      <option value="Hawaii">(GMT-10:00) Hawaii</option>
      <option value="Alaska">(GMT-09:00) Alaska</option>
      <option value="Pacific Time (US & Canada)">(GMT-08:00) Pacific Time (US & Canada)</option>
      <option value="Arizona">(GMT-07:00) Arizona</option>
      <option value="Mountain Time (US & Canada)">(GMT-07:00) Mountain Time (US & Canada)</option>
      <option value="Central Time (US & Canada)">(GMT-06:00) Central Time (US & Canada)</option>
      <option value="Eastern Time (US & Canada)">(GMT-05:00) Eastern Time (US & Canada)</option>
    </select>
  </div>
</body>
</html>

In its header it loads the blue-ridge JavaScript library, which in turn loads Screw.Unit and ultimately our spec.js test file (based on corresponding file name), so ninja_search.html will cause a file spec/ninja_search_spec.js to be loaded.

To run our first test just load up the spec/fixtures/ninja_search.html file into your browser.

Your first test will fail. But that’s ok, that’s the point of TDD. Red, green, refactor.

Simple passing code

So now we need some code to make the test pass.

Create a file public/ninja_search.js and something like the following should work:

(function($){
  $(function() {
    $('select').each(function(index) {
      var id = $(this).attr('id');

      // create the Ninja Search button, with rel attribute referencing corresponding >select id="...">
      $('> class="ninja_search_activation" rel="' + id + '">ninja search>/a>')
      .insertAfter($(this));
    });
  });
})(jQuery);

Reload your test fixtures HTML file and the test should pass.

Now rinse and repeat. The final suite of tests and fixture files for Ninja Search JS are on github.

Building a Greasemonkey script

Typically Greasemonkey scripts are all-inclusive affairs. One JavaScript file, named my_script.user.js, typically does the trick.

I decided I wanted a thin Greasemonkey script that would dynamically load my ninja-search.js, and any stylesheets and dependent libraries. This would allow people to install the thin Greasemonkey script once, and I can deploy new versions of the actual code base over time without them having to re-install anything.

Ultimately in production, the stylesheets, images, and JavaScript code would be hosted on the intertubes somewhere. Though during development that would be long-winded and painful to push the code to a remote host just to run tests.

So I have three Greasemonkey scripts:

• public/ninja_search.dev.user.js – loads each dependent library and asset from the local file system
• public/ninja_search.local.user.js – loads compressed library and asset from the local file system
• public/ninja_search.user.js – loads compressed library and assets from remote server

Let’s ignore the optimisation of compressing dependent JavaScript libraries for the moment and just look at the dev.user.js and user.js files.

The two scripts differ in the target host from which they load assets and libraries. ninja_search.dev.user.js loads them from the local machine and ninja_search.user.js loads them from a remote server.

For example ninja_search.dev.user.js loads local dependencies like this:

require("http://ninja-search-js.local/jquery.js");
require("http://ninja-search-js.local/ninja_search.js");

And ninja_search.user.js loads remote dependencies like this:

require("http://drnic.github.com/ninja-search-js/dist/jquery.js");
require("http://drnic.github.com/ninja-search-js/dist/ninja_search.js");

In the final version of ninja_search.user.js we load a simple, conpressed library containing jquery, our code, and other dependencies, called ninja_search_complete.js.

Using Passenger to server local libraries

The problem with loading local JavaScript libraries using the file:// protocol, inferred earlier, is that it doesn’t work. So if I can’t load libraries using file:// then I must use the http:// protocol. That means I must route the requests through Apache/Ningx.

Fortunately there is a very simple solution: use Phusion Passenger which serves a “web app’s” public folder automatically. That’s why all the javascript, CSS and image assets have been placed in a folder public instead of src or lib or javascript.

On my OS X machine, I moved the repository folder into my Sites folder and wired up the folder as a Passenger web app using PassengerPane. It took 2 minutes and now I had http://ninja-search.local as a valid base URL to serve my JavaScript libraries to my Greasemonkey script.

Testing the Greasemonkey scripts

I can only have one of the three Greasemonkey scripts installed at a time, so I install the ninja-search.dev.user.js file to check that everything is basically working inside a browser on interesting, foreign sites (outside of the unit test HTML pages).

Once I’ve deployed the JavaScript files and assets to the remote server I can then install the ninja-search.user.js file (so can you) and double check that I haven’t screwed anything up.

Deploying via GitHub Pages

The normal, community place to upload and share Greasemonkey scripts is userscripts.org. This is great for one file scripts, though if your script includes CSS and image assets, let alone additional JavaScript libraries, then I don’t think its as helpful, which is a pity.

So I decided to deploy the ninja-search-js files into the project’s own GitHub Pages site.

After creating the GitHub Pages site using Pages Generator, I then pulled down the gh-pages branch, and then linked (via submodules) that branch into my master branch as website folder.

Something like:

git checkout origin/gh-pages -b gh-pages
git checkout master
git submodule add -b gh-pages git@github.com:drnic/ninja-search-js.git website

Now I can access the gh-pages branch from my master branch (where the code is).

Then to deploy our Greasemonkey script we just copy over all the public files into website/dist, and then commit and push the changes to the gh-pages branch.

mkdir -p website/dist
cp -R public/* website/dist/
cd website
git commit -a "latest script release"
git push origin gh-pages
cd ..

Then you wait very patiently for GitHub to deploy your latest website, which now contains your Greasemonkey script (dist/ninja-search.user.js) and all the libraries (our actual code), stylesheets and images.

Summary

Greasemonkey scripts might seem like small little chunks of code. But all code starts small and grows. At some stage you’ll wish you had some test coverage. And later you’ll hate yourself for ever having release the bloody thing in the first place.

I wrote all this up to summarise how I’d done TDD for the Ninja Search JS project, which is slightly different from how I added test cases to _why’s the octocat’s pajamas greasemonkey script when I first started hacking with unit testing Greasemonkey scripts. The next one will probably be slightly different again.

I feel good about the current project structure, I liked Screw.Unit and blue-ridge, and I’m amused by my use of GitHub Pages to deploy the application itself.

If anyone has any ideas on how this could be improved, or done radically differently, I’d love to hear them!

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Send an email to rails@mocra.com about your current/future projects. Dare us to be more awesome!

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In cucumber, each scenario step in a .feature file matches to a Given, When, Then step definition. The step definitions are normal Ruby code. First class, bonnified, honky-tonk Ruby code. And what’s the one thing we love to do to Ruby code on a rainy Sunday afternoon? Refactor it. Turn messy code into readable “return in 50 years, on the time capsule, and get back to work quickly” code.

In Cucumber we use a special, until-now unknown, magic technique for refactoring step definitions. They are called “Ruby methods”. Oooh, feel the magic. You take some code in a step definition and you refactor it into a method. And you’re done. For example:

When /I fill in the Account form/ do
  fill_in("account_name", :with => "Mocra")
  fill_in("account_abn", :with => "12 345 678 901")
  click_button("Submit")
end

Could be refactored into:

When /I fill in the Account form/ do
  fill_in_account_form
end

def fill_in_account_form
  fill_in("account_name", :with => "Mocra")
  fill_in("account_abn", :with => "12 345 678 901")
  click_button("Submit")
end

Good work. Or is it? No, we’ve done something a little naughty. We’ve polluted the global object space with our method and turns out it just isn’t necessary. There’s a nicer way and a clean idiom for how/where to write helper methods.

Annoyingly, that idiom broke with the release of Cucumber 0.3. So I’ll introduce both so you can fix any bugs that you spot and know how to fix them.

The solution is to understand the existence of the World object and the clean technique for writing features/support/foobar_helpers.rb libraries of helper methods.

Introducing the World object

To ensure that each cucumber scenario starts with a clean slate, your scenarios are run upon a blank Object.new object. Or in a Rails project its a new Rails test session ActionController::IntegrationTest.

These are called World objects (see cucumber wiki). You pass in a specific World object you’d like to use, else it defaults to Object.new For a Rails project, you’re using Cucumber::Rails::World.new for your world object each time, which is a subclass of ActionController::IntegrationTest.

The benefit of a World object starting point for each scenario is that you can add methods to it, that won’t affect the rest of the Ruby world you live in: which will be the Cucumber runner. That is, you cannot accidently blow up Cucumber.

Extending the World object

Step 1, put methods in a module. Step 2, add the module to your World object.

So that we’re all extending Cucumber in the same way, there is a folder for where your helper methods should be stored, and a programming idiomatic way to do it. It has changed slight from Cucumber 0.2 to 0.3 so I’ll show both.

For our helper method fill_in_account_form above:

1. Create features/support/form_submission_helpers.rb (its automatically loaded)
2. Wrap the helper method in a module module FormSubmissionHelpers ... end
3. Tell Cucumber to include the module into each World object for each Scenario

In Cucumber 0.3+ your complete helper file would look like:

module FormSubmissionHelpers
  def fill_in_account_form
    fill_in("account_name", :with => "Mocra")
    fill_in("account_abn", :with => "12 345 678 901")
    click_button("Submit")
  end
end
World(FormSubmissionHelpers)

For Cucumber 0.2 your complete helper file might have looked like:

module FormSubmissionHelpers
  def fill_in_account_form
    fill_in("account_name", :with => "Mocra")
    fill_in("account_abn", :with => "12 345 678 901")
    click_button("Submit")
  end
end
World do |world|
  world.extend FormSubmissionHelpers
end

Where the difference is the last part of the file. This mechanism is deprecated and results in the following error message after upgrading to Cucumber 0.3:

/Library/Ruby/Gems/1.8/gems/cucumber-0.3.0/bin/../lib/cucumber/step_mother.rb:189:in `World': You can only pass a proc to #World once, but it's happening (Cucumber::MultipleWorld)
in 2 places:

vendor/plugins/cucumber/lib/cucumber/rails/world.rb:72:in `World'
vendor/plugins/email-spec/lib/email_spec/cucumber.rb:18:in `World'

Summary

Refactor step definitions. Put it in features/support/…_helpers.rb files, inside modules that are assigned to the World object.

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Got a simple app you want to build? Allocate 5 minutes for initial code generation, slice setup, and initial deployment. All from the command line. In one command. Booya!

How long does it take to start a new Rails project? Surely just a moment? rails new_project -m path/to/some/template.rb

But your application isn’t deployed yet. The DNS isn’t ready, the remote slice doesn’t exist or the config for this new application isn’t setup. Heck, the code hasn’t even been pushed to a non-existent remote repository yet.

And what if you’re going to use something like twitter_auth for authentication? You’ll need to register your application with Twitter at http://twitter.com/oauth_clients.

All these things could be automated, surely. Surely?

If they were then you’d have a “one click” command. A new Rails app, pushed into production, and ready to rock and roll. Complete with either restful_authentication or twitter-based oauth integration.

What does a “one click” rails and deploy command look like?

cd Sites
rails -m rails-templates/mocra.rb default-twitter-auth-app

1. restful_authentication
2. twitter_auth
Which user authentication system? 2

1. mocra-primary
2. mocra-secondary
3. crazy-pron-sites
Install http://default-twitter-auth-app.mocra.com application on which slice? 3^H1

1. drnic
2. mocra
Which twitter user?  1

Then you wait 3 minutes and 53 seconds.

Then you visit http://default-twitter-auth-app.mocra.com and it is working. You click the “Protected” link and you are redirected to Twitter to click the “Allow” link. You return to the app. You are registered with an account and logged in. You see your own face. You rock.

The rest of the article shows you how to test run it yourself, explain the dependencies and how to install them, and how to unit test your own templates to do similarly fancy things. Hopefully its helpful.

WAITING A MINUTE – is this tutorial destructive to my precious slices?

It is safe. IF you have an existing slicehost slice that was created with the latest deprec gem.

Perhaps backup your slice anyway. But it should be safe.

Deprec installs each application in its own folder and the apache settings are in their own file etc. But when deprec installs apache, passenger, etc it may put them in places you aren’t expecting. It might not. I just can’t promise anything.

Testimonial that the tutorial works

Ryan Bigg offers the following testimonial to encourage you to actually try out the tutorial:

“I have, dear readers, with as little effort as a few keystrokes, an an application base that allows my users to sign up using their twitter credentials. I have my code base here on my machine, and the running application in production over there at http://ryan.mocra.com” Ryan Bigg (radar)

Required gems for the template

There are a couple of one-time-only steps to run to install some gems and setup github and slicehost API keys locally.

gem install highline
gem install deprec
gem install defunkt-github --source http://gems.github.com
gem install booster-slicehost-tools --source=http://gems.github.com

To setup the github gem with your API key:

* login to [http://github.com/](http://github.com/)
* click [account](https://github.com/account)
* click "Global Git Config"
* copy and paste the two lines of config into the terminal to install the config

The github gem will now use this configuration automatically.

To setup the slicehost gem with your API key:

slicehost-slice list
Please enter your API key since you did not provide one:

To get your slicehost API:

• login to https://manage.slicehost.com
• click “Account”
• click API Access
• click “Enable API Access”
• copy + paste the API Password into the terminal above

Required gems and steps for using twitter_auth

My fork of the twitter gem includes a twitter register_oauth ... command. If John integrates the code, or writes his own, I’ll drop my fork and rewrite my template to use his gem. Til then use this one.

gem install drnic-twitter --source=http://gems.github.com
twitter install
twitter add

And enter your twitter account details. You can run the last command any number of times to add personal and corporate/product twitter accounts. I am really impressed with the internals of this gem – it stores your data in a sqlite3 gem and uses ActiveRecord models to retrieve it. Might create a generator for this in newgem. I also liked the use of the main gem for its command definition. Anyway, we’re off the topic.

Cloning and running the rails-templates

Imagine the above steps were “Buy an Xbox 360. Buy Guitar Hero.” Now its the final step. It’s time to rock.

cd ~/Sites
git clone git://github.com/drnic/rails-templates.git
DOMAIN=yourdomain.com ORGANIZATION="Your Company of Legends" rails -m rails-templates/mocra.rb my_app

A few minutes later you can open http://my-app.yourdomain.com in a browser. It will have restful_authentication or twitter oauth integration all setup and working (except email settings for restful_authentication).

It makes me very happy watching it work.

If the above command has stalled after printing ‘executing slicehost-slice list’ then you haven’t set up your slicehost API key. See the instructions above.

Dirty, nasty assumptions?

How can you deploy an entire app and have it up and running without some more configuration? Surely… surely I’ve made some nasty assumptions and come up with some dirty defaults?

Yes.

Your application url will be my-app-name.mocra.com. The subdomain is a dasherized version of your application’s folder name. Use DOMAIN=mycompany.com to change the domain.

Your local and remote database is mysql, accessible with user root and no password. I… look… you see there was this dog… and he ate my homework… it wasn’t me… there was an earthquate, a volcano, a flood… it wasn’t me!

You are deploying to slicehost. I do. It has command-line applications to manage slices and DNS. Since I’m deploying to a subdomain of mocra.com I use slicehost to create a CNAME in the DNS.

Your target slice already exists and has been built using the latest deprec. The template let’s you select an existing slicehost slice to use. If you don’t have one that was built with deprec, perhaps create a new one.

Gems? Plugins? Yes this template installs the ones that I want. That’s the point of rails templates – you create your own set of defaults.

What do I do to get my own uber-template?

Copy + paste the mocra.rb template and hack in your configuration. Fork the github project and push up your file so others can see your awesomeness.

See the section on unit testing templates too.

What’s missing?

The primary thing that I want that I haven’t gotten around to writing/fixing/finding a solution is the creation of private, company github projects. That is, instead of public/open-source, personal projects using github create-from-local.

I guess I would want a github create-from-local --private flag to create a private repo instead of a public repo.

Then I’d want the github gem to know that I live in a world of multiple github accounts: my personal account (drnic) and my company’s account (mocra). That is, I’ll want new private company projects to go on the company account.

And then I’ll want it to add me (drnic) as a collaborator. Or a whole group of people.

Since the github gem currently derives its user + API token information from your global git config (git config --get github.user), instead of a nice external sqlite3 database like the twitter gem, I’m not sure what the best/correct data structure would be to add multiple user support to the github gem.

Or perhaps the github create-from-local mechanism should be extracted out of the github gem all together into a github-admin gem which would have multiple users, create public/private repos, add collaborators etc. Yeah, that might be better.

Want a default application theme?

The template will attempt to invoke a generator app_layout if it can find it. Watch the railscast on generators for an example of how to create a local generator and he gives an example of creating a default application theme generator. That’s why all the railscasts applications look the same!

Bonus section: unit testing a Rails template

If you look in the rails-templates project you cloned you’ll see a spec folder. There is a mock template_runner.rb which is used by the spec/mocra/template_spec.rb. This way I can stub out calls to command-line tools like slicehost-slice list and twitter register_oauth and check that the template installs the correct plugins, creates the correct files, etc without actually installing or creating anything.

More importantly its a lot bloody faster to run than the full template.

If you’re creating Rails templates with interesting logic in them then writing some unit tests for your template might be a helpful idea to save time.

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My testimonial for Cucumber still stands even in 2009. In fact I promise to let you know when I don’t think Cucumber is the bees-knees of integration testing. I love the step-by-step English instructions of user usage scenarios backed by a simple Ruby DSL for describing real actions on your application for each step.

For testing Rails apps, Cucumber defaults to using Webrat on top of Rails’ own integration sessions. With Webrat you actually test that your views match to your controller actions. If I click the “Submit” button, then it checks that it invokes an available action correctly. Before Cucumber I could appreciate the merit of Webrat alone, but the two tools combined are instant superheroes of my Rails development crime fighting team. That is, like any superhero TV show at least once every 30 minutes you find yourself saying “Thank you Mr Cucumber and your trusty sidekick Webrat, you’re my heroes”. (BTW, I’m not alone in this analogy)

Testing emails

But I wanted to test emails. More interestingly, emails containing links back into my application. Like an activation email on sign up.

Specifically, I wanted a cucumber scenario like this:

Scenario: Signup for new account
  Given I am on the signup form
  When I fill in "Email" with "drnic@mocra.com"
  And I press "Join"
  Then I should see "An activation email has been sent"
  And I should receive an activation email
  When I click the activation email link
  Then I should see "Your account is active"

Within this scenario there are 7 steps. Lines 2, 3, 4 and 7 match to steps from the generated webrat_steps.rb file when you install cucumber.

Line 1 also matches to a webrat step definition. But it requires that you define what “the signup form” maps to in your routes. So you need to update features/support/paths.rb to specify what “the signup form” url is:

module NavigationHelpers
  def path_to(page_name)
    case page_name
    when /the signup form/
      signup_path
    end
  end
end

So, that leaves us with lines 5 and 6.

email-spec plugin

I’m happy using the email-spec gem/plugin from Ben Mabey, who is also the lead maintainer of the awesome Cucumber TextMate bundle and did a wonderful presentation on Outside-In Development with Cucumber at the recent Mountain West RubyConf (lots of great videos available)

To install as a plugin:

script/plugin install git://github.com/bmabey/email-spec.git

Then add the following line to your *feature/support/env.rb* file:

require 'email_spec/cucumber'

Finally, the plugin comes with some bonus cucumber step definitions which wrap around lots of nice helpers:

script/generate email_spec

Using email-spec step definitions

Let’s ignore my desired lines 5 and 6 above and use the step definitions that we get with email-spec. We can replace the two lines with the following:

And I should receive an email
When I open the email
Then I should see "Please activate your new account" in the subject
When I click the first link in the email

Update: The last line didn’t used to be in email-spec but it now is. I’ve removed the example from this article.

I did all this for an existing application and every line of the scenario tested positive/green. Yay!

Refactoring four steps into two

For the sake of demonstration, you now might want to refactor these four steps into two steps to keep your scenarios nice and readable.

That is, how can we convert these 4 steps into our original lines 5 and 6?

The quickest way is to copy and paste the lines and slap some quotes around the text:

Then /^I should receive an activation email$/ do |email|
  Then 'I should receive an email'
  When 'I open the email'
  Then 'I should see "Please activate your new account" in the subject'
end

When /^I click the activation email link$/ do
  When 'I click the first link in the email'
end

That’s right, you can use Given/When/Then as invocation methods as well as step definition methods. If you don’t pass these methods a do…end block then they will match/find/invoke a step rather than define a new one. Very cool.

Alternately, you could implement the two steps using the underlying email helper methods provided by the email-spec plugin:

Then /^I should receive an activation email$/ do
  unread_emails_for(current_email_address).size.should == 1
  open_email(current_email_address)
  current_email.should have_subject(/Please activate your new account/))
end

When /^I click the activation email link$/ do
  click_first_link_in_email
end

Your choice.

Configuring current_email_address

All the email-spec helper methods assume that the “I” in the scenario has an email address. It uses a method current_email_address for this.

You must change the current_email_address method in the email_steps.rb file to pull out email addresses from wherever they might be located within any given scenario.

For example, here is one definition of the method from one of my projects:

def current_email_address
  @email || (@current_user && @current_user.email) || "drnic@mocra.com"
end

Summary

With Cucumber and email-spec it is very easy to send and test emails. So my thanks go to Ben Mabey for this plugin.

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