heroku autotag deploy scripts

deploy.rake

require 'rake'

['sandbox', 'staging', 'production'].each do |env|
  desc "Deploy the given git tag and tag to #{env}"
  task "#{env}:deploy", :tag do |_, args|
    CodePusher.new(env, args[:tag]).deploy!
  end

  desc "Rollback #{env} to tag"
  task "#{env}:rollback", :tag do |_, args|
    CodePusher.new(env,  args[:tag]).rollback!
  end
end


class CodePusher
  HEROKU_APP_PREFIX="your_heroku_app_name"

  def initialize(environment_name, tag)
    @env = environment_name
    @tag = tag || previous_deploy
    @heroku_app_name = "#{HEROKU_APP_PREFIX}-#{@env}"
  end

  def deploy!
    puts green("DEPLOYING TAG: = #{@tag} = to heroku app #{@heroku_app_name}")
    push! && tag_ref_with(@env) && migrate_and_restart
    puts green("Win!")
  end

  def rollback!
    puts green("Rolling back #{@heroku_app_name} to #{@tag}")

    stop_the_presses!

    enter_maintenance!
    target_migration = `git checkout #{@tag} && ls db/migrate/ | tail -n1`.match(/(\d+)_.*/)[1]
    migrate_down!(target_migration)
    push!(:force => true)

    tag_ref_with(@env)
    tag_ref_with("#{@env}-rollback")
    migrate_and_restart
    exit_maintenance!

    `git checkout master`
    puts yellow("Rollback successful, make sure you are working on the right branch, currently master")
  end

  protected

  def previous_deploy
    last_two_revisions = `autotag list #{@env} | tail -n2 | awk {'print $1'}`
    previous_deploy = last_two_revisions.split(' ').to_a[0]
  end

  def tag_ref_with(env_name)
    timestamp = AutoTagger::Base.new({}).send(:timestamp)
    new_tag = "#{env_name}/#{timestamp}"
    command = [%{git fetch origin refs/tags/*:refs/tags/*},
               %{git update-ref refs/tags/#{new_tag} #{@tag}},
               %{git push origin refs/tags/*:refs/tags/*}].join(" && ")
    system(command) || raise("failed to tag")
  end

  def push!(opts={})
    puts green("Pushing #{@tag} to #{@heroku_app_name}")
    system("git push #{"--force" if opts[:force]} #{@env} +#{@tag}:master") || raise("failed to push to heroku")
  end

  def migrate_and_restart
    system(%{heroku rake db:migrate --app #{@heroku_app_name}}) || raise("migration failed")
    system(%{heroku restart --app #{@heroku_app_name}}) || raise("restarting heroku app failed")
  end

  def stop_the_presses!
    file_name = "stop_the_presses_#{Time.now.to_i}_spec.rb"
    system(%{cp script/support/stop_the_presses_spec.rb spec/lib/#{file_name}}) || raise("couldn't copy stop the presses")
    system(%{git add spec/lib/#{file_name}}) || raise("couldn't git add stop the presses")
    system(%{git ci -m "Stop the presses! ! We are rolling back. Add a failing test to prevent futher auto deploys until reolved." }) || raise("couldn't commit stop the presses")
    system(%{git push origin master}) || raise("couldn't push stop the presses")
  end

  def enter_maintenance!
    puts green('Entering Maintenance Mode on heroku')
    system("heroku maintenance:on --app #{@heroku_app_name}") || raise("failed to turn maintenance mode on")
  end

  def exit_maintenance!
    puts green("Turning the app back on, everything should be happy :)")
    system "heroku maintenance:off --app #{@heroku_app_name}" || raise("failed to turn maintenance mode off")
  end

  def migrate_down!(target_migration)
    puts green("Migrating down to #{target_migration}")
    system("heroku rake db:migrate:down VERSION=#{target_migration} --app #{@heroku_app_name}") || raise("failed to migrate database down")
  end

  def colorize(text, color_code)
    "\e[#{color_code}m#{text}\e[0m"
  end

  def green(text)
    colorize(text, 32)
  end

  def yellow(text)
    colorize(text, 33)
  end
end

LICENSE

The MIT License (MIT)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.