Sample Unicorn Configuration File

unicorn.rb

# _*_ coding: utf-8 _*_

require 'yaml'
require 'erb'

# source: http://d.hatena.ne.jp/milk1000cc/20100804/1280893810

# Use at least one worker per core if you're on a dedicated server,
# more will usually help for _short_ waits on databases/caches
worker_processes 4

# Make sure unicorn worker process doesn't kill itself if page takes longer to
# load
timeout 60

# Help ensure your application will always spawn in the symlinked
# "current" directory that Capistrano sets up.

# this will evaluate to something like "/Users/joelam/Projects/Vitrue/tabs"
# contributed by Kyle Bock
rails_root = File.expand_path('../..', __FILE__)
working_directory rails_root

# listen on a Unix domain socket
# directory path_to_project/tmp/sockets must exist
listen File.expand_path('tmp/sockets/unicorn.sock', ENV['RAILS_ROOT']), :backlog => 64

# pid
# directory path_to_project/tmp/pids must exist
pid File.expand_path('tmp/pids/unicorn.pid', ENV['RAILS_ROOT'])

# By default, the Unicorn logger will write to stderr.
# Additionally, ome applications/frameworks log to stderr or stdout,
# so prevent them from going to /dev/null when daemonized here:
stderr_path File.expand_path('log/unicorn.log', ENV['RAILS_ROOT'])
stdout_path File.expand_path('log/unicorn.log', ENV['RAILS_ROOT'])

# combine REE with "preload_app true" for memory savings
# http://rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
preload_app true

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

  old_pid = "#{ server.config[:pid] }.oldbin"
  unless old_pid == server.pid
    begin
      # SIGTTOU だと worker_processes が多いときおかしい気がする
      Process.kill :QUIT, File.read(old_pid).to_i
    rescue Errno::ENOENT, Errno::ESRCH
    end
  end
end

after_fork do |server, worker|
  if defined?(Rails)
    ActiveRecord::Base.establish_connection
  else
    if defined?(ActiveRecord::Base)
      env = ENV['RAILS_ENV'] || ENV['RACK_ENV'] || 'development'

      path = File.expand_path('../database.yml', __FILE__)
      file = File.open(path, 'r')
      template = ERB.new(file.read).result(binding)
      config = YAML.load(template).fetch(env, {})
      ActiveRecord::Base.establish_connection(config)
    end
  end
end