unicorn.rb with Capistrano

unicorn.rb

# https://github.com/tablexi/capistrano3-unicorn/blob/master/examples/unicorn.rb

worker_processes 2
listen 12345

before_exec do |server|
  ENV['BUNDLE_GEMFILE'] = '/var/tmp/foobar/current/Gemfile'
end

shared_path = '/var/tmp/foobar/shared'
pid File.expand_path('tmp/unicorn.pid', shared_path)
listen File.expand_path('tmp/unicorn.sock', shared_path)

stderr_path File.expand_path('log/foobar_unicorn_stderr.log', shared_path)
stdout_path File.expand_path('log/foobar_unicorn_stdout.log', shared_path)

preload_app true # ダウンタイムをなしにする

before_fork do |server, worker|
  defined?(ActiveRecord::Base) and
      ActiveRecord::Base.connection.disconnect!

  old_pid = "#{server.config[:pid]}.oldbin"
  if File.exists?(old_pid) && server.pid != old_pid
    begin
      Process.kill("QUIT", File.read(old_pid).to_i)
    rescue Errno::ENOENT, Errno::ESRCH
    end
  end
end

after_fork do |server, worker|
  defined?(ActiveRecord::Base) and
      ActiveRecord::Base.establish_connection
end