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     restart <watch or group name>
  18     stop <watch or group name>
  19     monitor <watch or group name>
  20     unmonitor <watch or group name>
  21     load <file>
  22     log <watch name>
  23     status
  24     terminate
  25
  26   Options:
  27 EOF
  28
  29   opts.on("-cCONFIG", "--config-file CONFIG", "Configuration file") do |x|
  30     options[:config] = x
  31   end
  32
  33   opts.on("-pPORT", "--port PORT", "Communications port") do |x|
  34     options[:port] = x
  35   end
  36
  37   opts.on("-PFILE", "--pid FILE", "Where to write the PID file") do |x|
  38     options[:pid] = x
  39   end
  40
  41   opts.on("-lFILE", "--log FILE", "Where to write the log file") do |x|
  42     options[:log] = x
  43   end
  44
  45   opts.on("-D", "--no-daemonize", "Don't daemonize") do
  46     options[:daemonize] = false
  47   end
  48
  49   opts.on("-v", "--version", "Print the version number and exit") do
  50     options[:version] = true
  51   end
  52
  53   opts.on("-V", "Print extended version and build information") do
  54     options[:info] = true
  55   end
  56 end.parse!
  57
  58 if options[:version]
  59   require 'god'
  60
  61   # print version
  62   puts "Version #{God::VERSION}"
  63   exit!(0)
  64 elsif options[:info]
  65   require 'god'
  66
  67   puts "Version: #{God::VERSION}"
  68   puts "Polls: enabled"
  69   puts "Events: " + God::EventHandler.event_system
  70
  71   exit!(0)
  72 elsif command = ARGV[0]
  73   require 'god'
  74
  75   # a command was specified
  76
  77   # connect to remote drb
  78   DRb.start_service
  79   server = DRbObject.new nil, "druby://127.0.0.1:#{options[:port]}"
  80
  81   begin
  82     server.ping
  83   rescue DRb::DRbConnError
  84     puts "The server is not available (or you do not have permissions to access it)"
  85     exit!
  86   rescue => e
  87     puts e.message
  88     puts e.backtrace.join("\n")
  89     exit!
  90   end
  91
  92   if command == 'load'
  93     file = ARGV[1]
  94
  95     puts "Sending '#{command}' command"
  96
  97     code = File.read(file)
  98
  99     watches = server.running_load(code)
 100
 101     # output response
 102     puts 'The following watches were affected:'
 103     watches.each do |w|
 104       puts '  ' + w.name
 105     end
 106
 107     puts "Done"
 108   elsif command == 'status'
 109     watches = server.status
 110     watches.keys.sort.each do |name|
 111       state = watches[name][:state]
 112       puts "#{name}: #{state}"
 113     end
 114   elsif command == 'log'
 115     begin
 116       Signal.trap('INT') { exit!(0) }
 117       name = ARGV[1]
 118       t = Time.at(0)
 119       loop do
 120         print server.running_log(name, t)
 121         t = Time.now
 122         sleep 1
 123       end
 124     rescue God::NoSuchWatchError
 125       puts "No such watch"
 126     rescue DRb::DRbConnError
 127       puts "The server went away"
 128     rescue => e
 129       puts e.message
 130       puts e.backtrace.join("\n")
 131     ensure
 132       exit!(0)
 133     end
 134   elsif command == 'terminate'
 135     t = Thread.new { loop { STDOUT.print('.'); STDOUT.flush; sleep(1) } }
 136     if server.stop_all
 137       t.kill; STDOUT.puts
 138       puts 'Stopped all watches'
 139     else
 140       t.kill; STDOUT.puts
 141       puts 'Could not stop all watches within 10 seconds'
 142     end
 143
 144     begin
 145       server.terminate
 146       abort 'Could not stop god'
 147     rescue DRb::DRbConnError
 148       puts 'Stopped god'
 149       exit!(0)
 150     end
 151   else
 152     # get the name of the watch/group
 153     name = ARGV[1]
 154
 155     begin
 156       puts "Sending '#{command}' command"
 157       puts "This may take a few seconds depending on the grace periods assigned to your watches"
 158
 159       # send command
 160       watches = server.control(name, command)
 161
 162       # output response
 163       puts 'The following watches were affected:'
 164       watches.each do |w|
 165         puts '  ' + w.name
 166       end
 167     rescue God::InvalidCommandError
 168       abort "Command '#{command}' is not valid. Run 'god --help' for usage"
 169     end
 170   end
 171
 172   exit!(0)
 173 else
 174   # start god
 175   if !options[:daemonize]
 176     require 'god'
 177
 178     if options[:port]
 179       God.port = options[:port]
 180     end
 181
 182     load File.expand_path(options[:config])
 183   else
 184     pid = fork do
 185       begin
 186         require 'god'
 187
 188         log_file = options[:log] || "/dev/null"
 189
 190         STDIN.reopen "/dev/null"
 191         STDOUT.reopen(log_file, "a")
 192         STDERR.reopen STDOUT
 193
 194         puts "Starting god"
 195
 196         unless God::EventHandler.loaded?
 197           puts
 198           puts "***********************************************************************"
 199           puts "*"
 200           puts "* Event conditions are not available for your installation of god."
 201           puts "* You may still use and write custom conditions using the poll system"
 202           puts "*"
 203           puts "***********************************************************************"
 204           puts
 205         end
 206
 207         puts "Resetting file descriptors"
 208
 209         puts "Loading config"
 210
 211         if options[:port]
 212           God.port = options[:port]
 213         end
 214
 215         load File.expand_path(options[:config])
 216
 217         Signal.trap('HUP') {}
 218       rescue => e
 219         File.open('god.log', 'a') { |f| f.puts e.message + "\n" + e.backtrace }
 220         abort "!!! ERROR - See god.log !!!"
 221       end
 222     end
 223
 224     if options[:pid]
 225       File.open(options[:pid], 'w') { |f| f.write pid }
 226     end
 227
 228     ::Process.detach pid
 229
 230     exit!(0)
 231   end
 232 end