Simple Rake task for customizing deployment to Heroku

heroku_deploy.rake

# rake deploy:production master

# List of environments and their heroku git remotes
ENVIRONMENTS = {
  :staging => 'myapp-staging',
  :production => 'myapp-production'
}

namespace :deploy do
  ENVIRONMENTS.keys.each do |env|
    desc "Deploy to #{env}"
    task env do
      current_branch = `git branch | grep ^* | awk '{ print $2 }'`.strip

      Rake::Task['deploy:before_deploy'].invoke(env, current_branch)
      Rake::Task['deploy:update_code'].invoke(env, current_branch)
      Rake::Task['deploy:after_deploy'].invoke(env, current_branch)
    end
  end

  task :before_deploy, :env, :branch do |t, args|
    puts "Deploying #{args[:branch]} to #{args[:env]}"

    # Ensure the user wants to deploy a non-master branch to production
    if args[:env] == :production && args[:branch] != 'master'
      print "Are you sure you want to deploy '#{args[:branch]}' to production? (y/n) " and STDOUT.flush
      char = $stdin.getc
      if char != ?y && char != ?Y
        puts "Deploy aborted"
        exit
      end
    end
  end

  task :after_deploy, :env, :branch do |t, args|
    # add ENV config to heroku from local yml file
    config_vars = []
    env = args[:env]
    config = YAML.load_file("#{File.dirname(__FILE__)}/../config/heroku_config.yml")[env.to_s] rescue nil || {}
    config.each do |key, value|
      config_vars << "#{key.upcase}=#{value}"
    end
    puts "Adding #{config_vars.join(" ")} to ENV config at #{ENVIRONMENTS[args[:env]]}"
    system "heroku config:add #{config_vars.join(" ")} --app  #{ENVIRONMENTS[args[:env]]}"
    puts "Deployment Complete"
  end

  task :update_code, :env, :branch do |t, args|
    FileUtils.cd "#{File.dirname(__FILE__)}/../" do
      puts "Updating #{ENVIRONMENTS[args[:env]]} with branch #{args[:branch]}"
      system "git push heroku #{args[:branch]}:master"
    end
  end
end