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 begin
  10   options = {:daemonize => true, :port => 17165}
  11
  12   opts = OptionParser.new do |opts|
  13     opts.banner = <<-EOF
  14   Usage:
  15     Starting:
  16       god -c <config file> [-p <port> | -b] [-P <file>] [-l <file>] [-D]
  17
  18     Querying:
  19       god <command> <argument> [-p <port>]
  20       god <command> [-p <port>]
  21       god -v
  22       god -V (must be run as root to be accurate on Linux)
  23
  24     Commands:
  25       start <task or group name>         start task or group
  26       restart <task or group name>       restart task or group
  27       stop <task or group name>          stop task or group
  28       monitor <task or group name>       monitor task or group
  29       unmonitor <task or group name>     unmonitor task or group
  30       load <file>                        load a config into a running god
  31       log <task name>                    show realtime log for given task
  32       status                             show status of each task
  33       quit                               stop god
  34       terminate                          stop god and all tasks
  35
  36     Options:
  37   EOF
  38
  39     opts.on("-cCONFIG", "--config-file CONFIG", "Configuration file") do |x|
  40       options[:config] = x
  41     end
  42
  43     opts.on("-pPORT", "--port PORT", "Communications port (default 17165)") do |x|
  44       options[:port] = x
  45     end
  46
  47     opts.on("-b", "--auto-bind", "Auto-bind to an unused port number") do
  48       options[:port] = "0"
  49     end
  50
  51     opts.on("-PFILE", "--pid FILE", "Where to write the PID file") do |x|
  52       options[:pid] = x
  53     end
  54
  55     opts.on("-lFILE", "--log FILE", "Where to write the log file") do |x|
  56       options[:log] = x
  57     end
  58
  59     opts.on("-D", "--no-daemonize", "Don't daemonize") do
  60       options[:daemonize] = false
  61     end
  62
  63     opts.on("-v", "--version", "Print the version number and exit") do
  64       options[:version] = true
  65     end
  66
  67     opts.on("-V", "Print extended version and build information") do
  68       options[:info] = true
  69     end
  70   end
  71
  72   opts.parse!
  73
  74   if options[:version]
  75     require 'god'
  76
  77     # print version
  78     puts "Version #{God::VERSION}"
  79     exit!(0)
  80   elsif options[:info]
  81     require 'god'
  82
  83     puts "Version: #{God::VERSION}"
  84     puts "Polls: enabled"
  85     puts "Events: " + God::EventHandler.event_system
  86
  87     exit!(0)
  88   elsif command = ARGV[0]
  89     require 'god'
  90
  91     # a command was specified
  92
  93     # connect to remote drb
  94     DRb.start_service
  95     server = DRbObject.new nil, "druby://127.0.0.1:#{options[:port]}"
  96
  97     begin
  98       server.ping
  99     rescue DRb::DRbConnError
 100       puts "The server is not available (or you do not have permissions to access it)"
 101       exit!
 102     rescue => e
 103       puts e.message
 104       puts e.backtrace.join("\n")
 105       exit!
 106     end
 107
 108     if command == 'load'
 109       file = ARGV[1]
 110
 111       puts "Sending '#{command}' command"
 112
 113       unless File.exist?(file)
 114         abort "File not found: #{file}"
 115       end
 116
 117       watches = server.running_load(File.read(file), File.expand_path(file))
 118
 119       # output response
 120       puts 'The following watches were affected:'
 121       watches.each do |w|
 122         puts '  ' + w.name
 123       end
 124     elsif command == 'status'
 125       begin
 126         watches = server.status
 127         watches.keys.sort.each do |name|
 128           state = watches[name][:state]
 129           puts "#{name}: #{state}"
 130         end
 131       rescue => e
 132         puts e.message
 133         puts e.backtrace.join("\n")
 134       end
 135     elsif command == 'log'
 136       begin
 137         Signal.trap('INT') { exit!(0) }
 138         name = ARGV[1]
 139         t = Time.at(0)
 140         loop do
 141           print server.running_log(name, t)
 142           t = Time.now
 143           sleep 1
 144         end
 145       rescue God::NoSuchWatchError
 146         puts "No such watch"
 147       rescue DRb::DRbConnError
 148         puts "The server went away"
 149       rescue => e
 150         puts e.message
 151         puts e.backtrace.join("\n")
 152       end
 153     elsif command == 'quit'
 154       begin
 155         server.terminate
 156         abort 'Could not stop god'
 157       rescue DRb::DRbConnError
 158         puts 'Stopped god'
 159       end
 160     elsif command == 'terminate'
 161       begin
 162         t = Thread.new { loop { STDOUT.print('.'); STDOUT.flush; sleep(1) } }
 163         if server.stop_all
 164           t.kill; STDOUT.puts
 165           puts 'Stopped all watches'
 166         else
 167           t.kill; STDOUT.puts
 168           puts 'Could not stop all watches within 10 seconds'
 169         end
 170       rescue => e
 171         puts e.message
 172         puts e.backtrace.join("\n")
 173       end
 174
 175       begin
 176         server.terminate
 177         abort 'Could not stop god'
 178       rescue DRb::DRbConnError
 179         puts 'Stopped god'
 180       end
 181     else
 182       # get the name of the watch/group
 183       name = ARGV[1]
 184
 185       begin
 186         puts "Sending '#{command}' command"
 187
 188         t = Thread.new { loop { sleep(1); STDOUT.print('.'); STDOUT.flush; sleep(1) } }
 189
 190         # send command
 191         watches = server.control(name, command)
 192
 193         # output response
 194         t.kill; STDOUT.puts
 195         puts 'The following watches were affected:'
 196         watches.each do |w|
 197           puts '  ' + w.name
 198         end
 199       rescue God::InvalidCommandError
 200         t.kill rescue nil; STDOUT.puts
 201         abort "Command '#{command}' is not valid. Run 'god --help' for usage"
 202       rescue => e
 203         puts e.message
 204         puts e.backtrace.join("\n")
 205       end
 206     end
 207
 208     exit!(0)
 209   else
 210     # start god
 211     if !options[:daemonize]
 212       require 'god'
 213
 214       if options[:port]
 215         God.port = options[:port]
 216       end
 217
 218       if options[:config]
 219         unless File.exist?(options[:config])
 220           abort "File not found: #{options[:config]}"
 221         end
 222
 223         begin
 224           load File.expand_path(options[:config])
 225         rescue => e
 226           puts e.message
 227           puts e.backtrace.join("\n")
 228           abort "There was an error in your configuration file (see above)"
 229         end
 230       end
 231     else
 232       # trap and ignore SIGHUP
 233       Signal.trap('HUP') {}
 234
 235       pid = fork do
 236         begin
 237           require 'god'
 238
 239           log_file = options[:log] || "/dev/null"
 240
 241           unless God::EventHandler.loaded?
 242             puts
 243             puts "***********************************************************************"
 244             puts "*"
 245             puts "* Event conditions are not available for your installation of god."
 246             puts "* You may still use and write custom conditions using the poll system"
 247             puts "*"
 248             puts "***********************************************************************"
 249             puts
 250           end
 251
 252           # set port if requested
 253           if options[:port]
 254             God.port = options[:port]
 255           end
 256
 257           # load config
 258           if options[:config]
 259             unless File.exist?(options[:config])
 260               abort "File not found: #{options[:config]}"
 261             end
 262
 263             begin
 264               load File.expand_path(options[:config])
 265             rescue => e
 266               puts e.message
 267               puts e.backtrace.join("\n")
 268               abort "There was an error in your configuration file (see above)"
 269             end
 270           end
 271
 272           # reset file descriptors
 273           STDIN.reopen "/dev/null"
 274           STDOUT.reopen(log_file, "a")
 275           STDERR.reopen STDOUT
 276         rescue => e
 277           puts e.message
 278           puts e.backtrace.join("\n")
 279           abort "There was a fatal system error while starting god (see above)"
 280         end
 281       end
 282
 283       if options[:pid]
 284         File.open(options[:pid], 'w') { |f| f.write pid }
 285       end
 286
 287       ::Process.detach pid
 288
 289       exit!(0)
 290     end
 291   # else
 292   #   puts opts.help
 293   end
 294 rescue Exception => e
 295   puts e.message
 296   puts e.backtrace.join("\n")
 297   exit!(1)
 298 end