text: #!/usr/bin/env python
  """
  Copyright 2009 Lucio Torre <lucio.torre@canonical.com>
  
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
  
  http://www.apache.org/licenses/LICENSE-2.0
  
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  
  Will publish metrics over AMQP
  """
  import os
  import time
  from optparse import OptionParser
  
  from twisted.python.failure import Failure
  from twisted.internet.defer import deferredGenerator, waitForDeferred
  from twisted.internet import reactor, task
  from twisted.internet.protocol import ClientCreator
  from txamqp.protocol import AMQClient
  from txamqp.client import TwistedDelegate
  from txamqp.content import Content
  import txamqp.spec
  
  @deferredGenerator
  def writeMetric(metric_path, value, timestamp, host, port, username, password,
                  vhost, exchange, spec=None, channel_number=1, ssl=False):
  
      if not spec:
          spec = txamqp.spec.load(os.path.normpath(
              os.path.join(os.path.dirname(__file__), 'amqp0-8.xml')))
  
      delegate = TwistedDelegate()
  
      connector = ClientCreator(reactor, AMQClient, delegate=delegate,
                                vhost=vhost, spec=spec)
      if ssl:
          from twisted.internet.ssl import ClientContextFactory
          wfd = waitForDeferred(connector.connectSSL(host, port, 
                                                     ClientContextFactory()))
          yield wfd
          conn = wfd.getResult()
      else:
          wfd = waitForDeferred(connector.connectTCP(host, port))
          yield wfd
          conn = wfd.getResult()
  
      wfd = waitForDeferred(conn.authenticate(username, password))
      yield wfd
  
      wfd = waitForDeferred(conn.channel(channel_number))
      yield wfd
      channel = wfd.getResult()
  
      wfd = waitForDeferred(channel.channel_open())
      yield wfd
  
      wfd = waitForDeferred(channel.exchange_declare(exchange=exchange,
                                                     type="topic",
                                                     durable=True, 
                                                     auto_delete=False))
      yield wfd
  
      message = Content( "%f %d" % (value, timestamp) )
      message["delivery mode"] = 2
  
      channel.basic_publish(exchange=exchange, content=message,
                            routing_key=metric_path)
      wfd = waitForDeferred(channel.channel_close())
      yield wfd
  
  def main():
      parser = OptionParser(usage="%prog [options] <metric> <value> [timestamp]")
      parser.add_option("-t", "--host", dest="host",
                        help="host name", metavar="HOST", default="localhost")
  
      parser.add_option("-p", "--port", dest="port", type=int,
                        help="port number", metavar="PORT",
                        default=5672)
  
      parser.add_option("-u", "--user", dest="username",
                        help="username", metavar="USERNAME",
                        default="guest")
  
      parser.add_option("-w", "--password", dest="password",
                        help="password", metavar="PASSWORD",
                        default="guest")
  
      parser.add_option("-v", "--vhost", dest="vhost",
                        help="vhost", metavar="VHOST",
                        default="/")
  
      parser.add_option("-s", "--ssl", dest="ssl",
                        help="ssl", metavar="SSL", action="store_true",
                        default=False)
  
      parser.add_option("-e", "--exchange", dest="exchange",
                        help="exchange", metavar="EXCHANGE",
                        default="graphite")
  
      (options, args) = parser.parse_args()
  
      try:
        metric_path = args[0]
        value = float(args[1])
  
        if len(args) > 2:
          timestamp = int(args[2])
        else:
          timestamp = time.time()
  
      except ValueError:
        parser.print_usage()
        raise SystemExit(1)
  
      d = writeMetric(metric_path, value, timestamp, options.host, options.port,
                      options.username, options.password, vhost=options.vhost,
                      exchange=options.exchange, ssl=options.ssl)
      d.addErrback(lambda f: f.printTraceback())
      d.addBoth(lambda _: reactor.stop())
      reactor.run()
  
  if __name__ == "__main__":
      main()
  