serverspecで完結するテスト駆動インフラ構築 (Test-Driven-Infrastructure with serverspec) ref: http://qiita.com/sawanoboly/items/f2e60d69a336c426ef97

chef_and_rabbitmq_spec.rb

require 'spec_helper'

describe command('which chef-solo') do
  it {
    begin
      should return_exit_status(0)
    rescue => e
      puts e.message
      puts "======= Installing Omnibus Chef..."
      cmd = Serverspec::Type::Command.new('curl -L https://www.opscode.com/chef/install.sh | sudo bash')
      expect(cmd.return_exit_status?(0)).to be_true
    end
  }
end

describe package('git') do
  it {
    begin
      should be_installed
    rescue => e
      puts e.message
      puts "======= installing git..."
      cmd = serverspec::type::command.new('apt-get update && apt-get install -y git')
      expect(cmd.return_exit_status?(0)).to be_true
    end
  }
end

describe file('/var/chef/cookbooks/.git') do
  it {
    begin
      should be_directory
    rescue => e
      puts e.message
      puts "======= initializing cookbooks directory..."
      cmd = Serverspec::Type::Command.new('mkdir -p /var/chef/cookbooks')
      expect(cmd.return_exit_status?(0)).to be_true
      cmd = Serverspec::Type::Command.new('git init /var/chef/cookbooks')
      expect(cmd.return_exit_status?(0)).to be_true
      cmd = Serverspec::Type::Command.new('touch /var/chef/cookbooks/.gitkeep')
      expect(cmd.return_exit_status?(0)).to be_true
      cmd = Serverspec::Type::Command.new('cd /var/chef/cookbooks && git add . && git commit .gitkeep -m "empty init"')
      expect(cmd.return_exit_status?(0)).to be_true
    end
  }
end

describe package('rabbitmq-server') do
  it {
    begin
      should be_installed
    rescue => e
      puts e.message
      puts "======= installing rabbitmq by chef..."
      cmd = Serverspec::Type::Command.new('knife cookbook site install rabbitmq')
      expect(cmd.return_exit_status?(0)).to be_true
      cmd = Serverspec::Type::Command.new('chef-solo -o "rabbitmq"')
      expect(cmd.return_exit_status?(0)).to be_true
    end
  }
end

nginx_converge_spec.rb

require 'spec_helper'

describe package('nginx') do
  it {
    begin
      should be_installed
    rescue => e
      puts e.message
      puts "======= Installing Nginx..."
      cmd = Serverspec::Type::Command.new('apt-get update && apt-get install -y nginx')
      expect(cmd.return_exit_status?(0)).to be_true
    end
  }
end

nginx_spec.rb

require 'spec_helper'

describe package('nginx') do
  it { should be_installed }
end

run_rspec_converge

$ rspec -fd

Package "nginx"
expected Package "nginx" to be installed
======= Installing Nginx...
  should be true

Finished in 13.42 seconds
1 example, 0 failures

run_rspec_fails

Failures:

  1) Package "nginx" 
     Failure/Error: it { should be_installed }
       dpkg -s nginx && ! dpkg -s nginx | grep -E '^Status: .+ not-installed$'
       Package `nginx' is not installed and no info is available.
Use dpkg --info (= dpkg-deb --info) to examine archive files,
and dpkg --contents (= dpkg-deb --contents) to list their contents.
       expected Package "nginx" to be installed
     # ./spec/xxx.xxx.xxx.xxx/nginx_spec.rb:4:in `block (2 levels) in <top (required)>'

Finished in 1.01 seconds
1 examples, 1 failures

run_rspec_up_to_date

$ rspec -fd

Package "nginx"
  should be installed

Finished in 1.03 seconds
1 example, 0 failures