vendor/rails/railties/lib/commands/ncgi/listener

   1 #!/usr/bin/env ruby
   2
   3 require 'stringio'
   4 require 'fileutils'
   5 require 'fcgi_handler'
   6
   7 def message(s)
   8   $stderr.puts "listener: #{s}" if ENV && ENV["DEBUG_GATEWAY"]
   9 end
  10
  11 class RemoteCGI < CGI
  12   attr_accessor :stdinput, :stdoutput, :env_table
  13   def initialize(env_table, input = nil, output = nil)
  14     self.env_table = env_table
  15     self.stdinput = input || StringIO.new
  16     self.stdoutput = output || StringIO.new
  17     super()
  18   end
  19
  20   def out(stream) # Ignore the requested output stream
  21     super(stdoutput)
  22   end
  23 end
  24
  25 class Listener
  26   include DRbUndumped
  27
  28   def initialize(timeout, socket_path)
  29     @socket = File.expand_path(socket_path)
  30     @mutex = Mutex.new
  31     @active = false
  32     @timeout = timeout
  33
  34     @handler = RailsFCGIHandler.new
  35     @handler.extend DRbUndumped
  36
  37     message 'opening socket'
  38     DRb.start_service("drbunix:#{@socket}", self)
  39
  40     message 'entering process loop'
  41     @handler.process! self
  42   end
  43
  44   def each_cgi(&cgi_block)
  45     @cgi_block = cgi_block
  46     message 'entering idle loop'
  47     loop do
  48       sleep @timeout rescue nil
  49       die! unless @active
  50       @active = false
  51     end
  52   end
  53
  54   def process(env, input)
  55     message 'received request'
  56     @mutex.synchronize do
  57       @active = true
  58
  59       message 'creating input stream'
  60       input_stream = StringIO.new(input)
  61       message 'building CGI instance'
  62       cgi = RemoteCGI.new(eval(env), input_stream)
  63
  64       message 'yielding to fcgi handler'
  65       @cgi_block.call cgi
  66       message 'yield finished -- sending output'
  67
  68       cgi.stdoutput.seek(0)
  69       output = cgi.stdoutput.read
  70
  71       return output
  72     end
  73   end
  74
  75   def die!
  76     message 'shutting down'
  77     DRb.stop_service
  78     FileUtils.rm_f @socket
  79     Kernel.exit 0
  80   end
  81 end
  82
  83 socket_path = ARGV.shift
  84 timeout = (ARGV.shift || 90).to_i
  85
  86 Listener.new(timeout, socket_path)