# run with: god -c /usr/local/etc/god/config.god
#
#

require 'rubygems'

require 'yaml'
require 'angel'

DEFAULT = {
  'servers' => '1',
  'address' => '127.0.0.1',
  'environment' => 'production',
  'user' => 'nobody',
  'group' => 'nobody',
  'web_server' => 'thin',
  'pid_file' => '/var/run/god-app.pid',
  'log_file' => '/var/log/god-app.log',
}

#God.load "/usr/local/etc/god/contacts.god"
Dir["/usr/local/etc/god/service/*.yml"].each do |config_file|
  config = DEFAULT.merge(YAML.load_file(config_file))
  config['app'] = File.basename(config_file, ".yml")
  
  raise "File #{config_file} is missing cwd definition" unless config['cwd']
  
  config['servers'].to_i.times do |n|
    this = config.merge('port' => config['port'] + n)
    Angel.set_pid_file(this)
    Angel.set_log_file(this)
    
    God.watch do |w|
      w.name          = Angel.process_name(this)
      w.group         = this['app']
      w.stop          = Angel.stop_cmd(this)
      w.start         = Angel.start_cmd(this)
      w.restart       = Angel.restart_cmd(this)
      w.interval      = 30.seconds
      w.start_grace   = 10.seconds
      w.restart_grace = 10.seconds
      w.pid_file      = this['pid_file']
      w.uid           = this['user']
      w.gid           = this['group']
      
      # clean pid file before start if necessary
      w.behavior(:clean_pid_file)
      
      # determine state on god startup
      w.transition(:init, { true => :up, false => :start }) do |on|
        on.condition(:process_running) do |c|
          c.running = true
        end
      end
      
      # determine when process has finished starting
      w.transition([:start, :restart], :up) do |on|
        on.condition(:process_running) do |c|
          c.running = true
        end
        
        # failsafe
        on.condition(:tries) do |c|
          c.times = 5
          c.transition = :start
        end
      end
      
      # start if process is not running
      w.transition(:up, :start) do |on|
        on.condition(:process_exits)
      end
      
      # Restart if memory or cpu usage is too high
      w.transition(:up, :restart) do |on|
        on.condition(:memory_usage) do |c|
          c.interval = 20
          c.above = 50.megabytes
          c.times = [3,5] # three out of five intervals
        end
        
        on.condition(:cpu_usage) do |c|
          c.interval = 10
          c.above = 10.percent
          c.times = [3,5] # three out of five intervals
        end
      end
      
      # Life!!!
      w.lifecycle do |on|
        on.condition(:flapping) do |c|
          c.to_state     = [:start, :restart]
          c.times        = 5
          c.within       = 5.minutes
          c.transition   = :unmonitored
          c.retry_in     = 10.minutes
          c.retry_times  = 5
          c.retry_within = 2.hours
        end
      end
    end
  end
end