unicorn.rb

dep 'unicorn configured', :path do
  requires 'unicorn config exists'.with(path)
  requires 'unicorn paths'.with(path)
end

dep 'unicorn config exists', :path do
  def unicorn_config
    path / 'config/unicorn.rb'
  end
  def unicorn_socket
    path / 'tmp/sockets/unicorn.socket'
  end
  met? { unicorn_config.exists? }
  meet { render_erb 'unicorn/unicorn.rb.erb', :to => unicorn_config }
end

dep 'unicorn paths', :root do
  def missing_paths
    %w[log tmp/pids tmp/sockets].reject {|p| (root / p).dir? }
  end
  met? { missing_paths.empty? }
  meet { missing_paths.each {|p| (root / p).mkdir } }
end

dep 'unicorn running', :app_root, :env do
  app_root.default('~/current')
  requires 'lsof.bin'
  met? {
    if !(app_root / 'config/unicorn.rb').exists?
      log "Not starting any unicorns because there's no unicorn config."
      true
    else
      running_count = shell('lsof -U').split("\n").grep(/#{Regexp.escape(app_root / 'tmp/sockets/unicorn.socket')}$/).count
      (running_count >= 3).tap {|result| # 1 master + 2 workers
        if result
          log_ok "This app has #{running_count} unicorn#{'s' unless running_count == 1} running (1 master + #{running_count - 1} workers)."
        elsif running_count > 0
          unmeetable! "This app is in an unexpected state: (1 master + #{running_count - 1} workers)."
        else
          log "This app has no unicorns running."
        end
      }
    end
  }
  meet {
    shell "bundle exec unicorn -D -E #{env} -c config/unicorn.rb", :cd => app_root
  }
end