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://localhost:#{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   end
  86
  87   if command == 'load'
  88     file = ARGV[1]
  89
  90     puts "Sending '#{command}' command"
  91
  92     code = File.read(file)
  93
  94     watches = server.running_load(code)
  95
  96     # output response
  97     puts 'The following watches were affected:'
  98     watches.each do |w|
  99       puts '  ' + w.name
 100     end
 101
 102     puts "Done"
 103   elsif command == 'status'
 104     puts server.status
 105   elsif command == 'log'
 106     begin
 107       Signal.trap('INT') { exit!(0) }
 108       name = ARGV[1]
 109       t = Time.at(0)
 110       loop do
 111         print server.running_log(name, t)
 112         t = Time.now
 113         sleep 1
 114       end
 115     rescue God::NoSuchWatchError
 116       puts "No such watch"
 117     rescue DRb::DRbConnError
 118       puts "The server went away"
 119     rescue => e
 120       puts e.message
 121       puts e.backtrace.join("\n")
 122     ensure
 123       exit!(0)
 124     end
 125   elsif command == 'terminate'
 126     if server.stop_all
 127       puts 'Stopped all watches'
 128     else
 129       puts 'Could not stop all watches within 10 seconds'
 130     end
 131
 132     begin
 133       server.terminate
 134       abort 'Could not stop god'
 135     rescue DRb::DRbConnError
 136       puts 'Stopped god'
 137       exit!(0)
 138     end
 139   else
 140     # get the name of the watch/group
 141     name = ARGV[1]
 142
 143     begin
 144       puts "Sending '#{command}' command"
 145
 146       # send command
 147       watches = server.control(name, command)
 148
 149       # output response
 150       puts 'The following watches were affected:'
 151       watches.each do |w|
 152         puts '  ' + w.name
 153       end
 154     rescue God::InvalidCommandError
 155       abort "Command '#{command}' is not valid. Run 'god --help' for usage"
 156     end
 157   end
 158
 159   exit!(0)
 160 else
 161   # start god
 162   if !options[:daemonize]
 163     require 'god'
 164
 165     if options[:port]
 166       God.port = options[:port]
 167     end
 168
 169     load File.expand_path(options[:config])
 170   else
 171     pid = fork do
 172       begin
 173         require 'god'
 174
 175         log_file = options[:log] || "/dev/null"
 176
 177         STDIN.reopen "/dev/null"
 178         STDOUT.reopen(log_file, "a")
 179         STDERR.reopen STDOUT
 180
 181         puts "Starting god"
 182
 183         unless God::EventHandler.loaded?
 184           puts
 185           puts "***********************************************************************"
 186           puts "*"
 187           puts "* Event conditions are not available for your installation of god."
 188           puts "* You may still use and write custom conditions using the poll system"
 189           puts "*"
 190           puts "***********************************************************************"
 191           puts
 192         end
 193
 194         puts "Resetting file descriptors"
 195
 196         puts "Loading config"
 197
 198         if options[:port]
 199           God.port = options[:port]
 200         end
 201
 202         load File.expand_path(options[:config])
 203
 204         Signal.trap('HUP') {}
 205       rescue => e
 206         File.open('god.log', 'a') { |f| f.puts e.message + "\n" + e.backtrace }
 207         abort "!!! ERROR - See god.log !!!"
 208       end
 209     end
 210
 211     if options[:pid]
 212       File.open(options[:pid], 'w') { |f| f.write pid }
 213     end
 214
 215     ::Process.detach pid
 216
 217     exit!(0)
 218   end
 219 end