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     if server.stop_all
 136       puts 'Stopped all watches'
 137     else
 138       puts 'Could not stop all watches within 10 seconds'
 139     end
 140
 141     begin
 142       server.terminate
 143       abort 'Could not stop god'
 144     rescue DRb::DRbConnError
 145       puts 'Stopped god'
 146       exit!(0)
 147     end
 148   else
 149     # get the name of the watch/group
 150     name = ARGV[1]
 151
 152     begin
 153       puts "Sending '#{command}' command"
 154       puts "This may take a few seconds depending on the grace periods assigned to your watches"
 155
 156       # send command
 157       watches = server.control(name, command)
 158
 159       # output response
 160       puts 'The following watches were affected:'
 161       watches.each do |w|
 162         puts '  ' + w.name
 163       end
 164     rescue God::InvalidCommandError
 165       abort "Command '#{command}' is not valid. Run 'god --help' for usage"
 166     end
 167   end
 168
 169   exit!(0)
 170 else
 171   # start god
 172   if !options[:daemonize]
 173     require 'god'
 174
 175     if options[:port]
 176       God.port = options[:port]
 177     end
 178
 179     load File.expand_path(options[:config])
 180   else
 181     pid = fork do
 182       begin
 183         require 'god'
 184
 185         log_file = options[:log] || "/dev/null"
 186
 187         STDIN.reopen "/dev/null"
 188         STDOUT.reopen(log_file, "a")
 189         STDERR.reopen STDOUT
 190
 191         puts "Starting god"
 192
 193         unless God::EventHandler.loaded?
 194           puts
 195           puts "***********************************************************************"
 196           puts "*"
 197           puts "* Event conditions are not available for your installation of god."
 198           puts "* You may still use and write custom conditions using the poll system"
 199           puts "*"
 200           puts "***********************************************************************"
 201           puts
 202         end
 203
 204         puts "Resetting file descriptors"
 205
 206         puts "Loading config"
 207
 208         if options[:port]
 209           God.port = options[:port]
 210         end
 211
 212         load File.expand_path(options[:config])
 213
 214         Signal.trap('HUP') {}
 215       rescue => e
 216         File.open('god.log', 'a') { |f| f.puts e.message + "\n" + e.backtrace }
 217         abort "!!! ERROR - See god.log !!!"
 218       end
 219     end
 220
 221     if options[:pid]
 222       File.open(options[:pid], 'w') { |f| f.write pid }
 223     end
 224
 225     ::Process.detach pid
 226
 227     exit!(0)
 228   end
 229 end