bin/god

   1 #!/usr/bin/env ruby
   2
   3 $:.unshift File.join(File.dirname(__FILE__), *%w[.. lib])
   4
   5 require 'rubygems'
   6 require 'optparse'
   7 require 'drb'
   8
   9 options = {:daemonize => true, :port => 17165}
  10
  11 OptionParser.new do |opts|
  12   opts.banner = <<-EOF
  13 Usage: god [command] [options]
  14
  15   Commands:
  16     start <watch or group name>
  17     stop <watch or group name>
  18     monitor <watch or group name>
  19     unmonitor <watch or group name>
  20     load <file>
  21     log <watch name>
  22     status
  23     terminate
  24
  25   Options:
  26 EOF
  27
  28   opts.on("-cCONFIG", "--config-file CONFIG", "Configuration file") do |x|
  29     options[:config] = x
  30   end
  31
  32   opts.on("-pPORT", "--port PORT", "Communications port") do |x|
  33     options[:port] = x
  34   end
  35
  36   opts.on("-PFILE", "--pid FILE", "Where to write the PID file") do |x|
  37     options[:pid] = x
  38   end
  39
  40   opts.on("-lFILE", "--log FILE", "Where to write the log file") do |x|
  41     options[:log] = x
  42   end
  43
  44   opts.on("-D", "--no-daemonize", "Don't daemonize") do
  45     options[:daemonize] = false
  46   end
  47
  48   opts.on("-v", "--version", "Print the version number and exit") do
  49     options[:version] = true
  50   end
  51
  52   opts.on("-V", "Print extended version and build information") do
  53     options[:info] = true
  54   end
  55 end.parse!
  56
  57 if options[:version]
  58   require 'god'
  59
  60   # print version
  61   puts "Version #{God::VERSION}"
  62   exit!(0)
  63 elsif options[:info]
  64   require 'god'
  65
  66   puts "Version: #{God::VERSION}"
  67   puts "Polls: enabled"
  68   puts "Events: " + God::EventHandler.event_system
  69
  70   exit!(0)
  71 elsif command = ARGV[0]
  72   require 'god'
  73
  74   # a command was specified
  75
  76   # connect to remote drb
  77   DRb.start_service
  78   server = DRbObject.new nil, "druby://127.0.0.1:#{options[:port]}"
  79
  80   begin
  81     server.ping
  82   rescue DRb::DRbConnError
  83     puts "The server is not available (or you do not have permissions to access it)"
  84     exit!
  85   rescue => e
  86     puts e.message
  87     puts e.backtrace.join("\n")
  88     exit!
  89   end
  90
  91   if command == 'load'
  92     file = ARGV[1]
  93
  94     puts "Sending '#{command}' command"
  95
  96     code = File.read(file)
  97
  98     watches = server.running_load(code)
  99
 100     # output response
 101     puts 'The following watches were affected:'
 102     watches.each do |w|
 103       puts '  ' + w.name
 104     end
 105
 106     puts "Done"
 107   elsif command == 'status'
 108     puts server.status
 109   elsif command == 'log'
 110     begin
 111       Signal.trap('INT') { exit!(0) }
 112       name = ARGV[1]
 113       t = Time.at(0)
 114       loop do
 115         print server.running_log(name, t)
 116         t = Time.now
 117         sleep 1
 118       end
 119     rescue God::NoSuchWatchError
 120       puts "No such watch"
 121     rescue DRb::DRbConnError
 122       puts "The server went away"
 123     rescue => e
 124       puts e.message
 125       puts e.backtrace.join("\n")
 126     ensure
 127       exit!(0)
 128     end
 129   elsif command == 'terminate'
 130     if server.stop_all
 131       puts 'Stopped all watches'
 132     else
 133       puts 'Could not stop all watches within 10 seconds'
 134     end
 135
 136     begin
 137       server.terminate
 138       abort 'Could not stop god'
 139     rescue DRb::DRbConnError
 140       puts 'Stopped god'
 141       exit!(0)
 142     end
 143   else
 144     # get the name of the watch/group
 145     name = ARGV[1]
 146
 147     begin
 148       puts "Sending '#{command}' command"
 149
 150       # send command
 151       watches = server.control(name, command)
 152
 153       # output response
 154       puts 'The following watches were affected:'
 155       watches.each do |w|
 156         puts '  ' + w.name
 157       end
 158     rescue God::InvalidCommandError
 159       abort "Command '#{command}' is not valid. Run 'god --help' for usage"
 160     end
 161   end
 162
 163   exit!(0)
 164 else
 165   # start god
 166   if !options[:daemonize]
 167     require 'god'
 168
 169     if options[:port]
 170       God.port = options[:port]
 171     end
 172
 173     load File.expand_path(options[:config])
 174   else
 175     pid = fork do
 176       begin
 177         require 'god'
 178
 179         log_file = options[:log] || "/dev/null"
 180
 181         STDIN.reopen "/dev/null"
 182         STDOUT.reopen(log_file, "a")
 183         STDERR.reopen STDOUT
 184
 185         puts "Starting god"
 186
 187         unless God::EventHandler.loaded?
 188           puts
 189           puts "***********************************************************************"
 190           puts "*"
 191           puts "* Event conditions are not available for your installation of god."
 192           puts "* You may still use and write custom conditions using the poll system"
 193           puts "*"
 194           puts "***********************************************************************"
 195           puts
 196         end
 197
 198         puts "Resetting file descriptors"
 199
 200         puts "Loading config"
 201
 202         if options[:port]
 203           God.port = options[:port]
 204         end
 205
 206         load File.expand_path(options[:config])
 207
 208         Signal.trap('HUP') {}
 209       rescue => e
 210         File.open('god.log', 'a') { |f| f.puts e.message + "\n" + e.backtrace }
 211         abort "!!! ERROR - See god.log !!!"
 212       end
 213     end
 214
 215     if options[:pid]
 216       File.open(options[:pid], 'w') { |f| f.write pid }
 217     end
 218
 219     ::Process.detach pid
 220
 221     exit!(0)
 222   end
 223 end