deploy.rb

#!/usr/bin/env ruby

require_relative '../config/boot'

require 'pathname'
require 'fileutils'
require 'json'
include FileUtils

# path to your application root.
APP_ROOT = Pathname.new File.expand_path('../../', __FILE__)

def system!(*args)
  system(*args) || abort("\n== Command #{args} failed ==")
end

chdir APP_ROOT do
  puts "\n== Checking requirements =="
  if ENV.has_key?('HEROKU_API_KEY')
    puts 'HEROKU_API_KEY is set'
  else
    STDERR.puts "Error: HEROKU_API_KEY environment variable is not set, exiting."
    abort
  end

  puts '== Installing dependencies =='
  system! 'gem install bundler --conservative'
  system('bundle check') || system!('bundle install')

  puts "\n== Retrieving application information =="
  require 'platform-api'
  client = PlatformAPI::connect(ENV['HEROKU_API_KEY'])

  config_file = File.read('app.json')
  puts "Found application config: app.json"
  app_name = JSON.parse(config_file)['name']
  puts "Found application: #{app_name}"

  pipeline = client.pipeline_coupling.info(app_name)['pipeline']
  puts "Found pipeline: #{pipeline['name']}"
  couplings = client.pipeline_coupling.list().find_all do |coupling|
    coupling['pipeline']['id'] == pipeline['id']
  end

  apps = client.app.list()
  staging_app_id = couplings.find { |coupling| coupling['stage'] == 'staging' }['app']['id']
  staging_app = apps.find { |app| app['id'] == staging_app_id }
  puts "Found staging app: #{staging_app['name']}"

  production_app_id = couplings.find { |coupling| coupling['stage'] == 'production' }['app']['id']
  production_app = apps.find { |app| app['id'] == production_app_id }
  puts "Found production app: #{production_app['name']}"

  puts "\n== Deployment =="
  puts "Promoting #{staging_app['name']} to production..."
  promotion = client.pipeline_promotion.create({
    'pipeline': { 'id': pipeline['id'] },
    'source': {
      'app': { 'id': staging_app['id'] }
    },
    'targets': [{
      'app': { 'id': production_app['id'] }
    }]
  })
  puts "Promoted #{staging_app['name']} successfully!"

  status = promotion['status']
  while status == 'pending'
    puts "Status is #{status}, waiting..."
    sleep(1)
    status = client.pipeline_promotion.info(promotion['id'])['status']
  end
  if status == 'completed'
    puts "Deployment completed."
  else
    STDERR.puts "Deployment failed: #{status}"
    abort
  end
end