chrome/test/pyautolib/remote_host.py

   1 #!/usr/bin/env python
   2 # Copyright (c) 2011 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 import cStringIO
   7 import os
   8 import pickle
   9 import socket
  10 import sys
  11
  12 import pyauto
  13
  14 class RemoteHost(object):
  15   """Class used as a host for tests that use the PyAuto RemoteProxy.
  16
  17   This class fires up a listener which waits for a connection from a RemoteProxy
  18   and receives method call requests. Run python remote_host.py
  19   remote_host.RemoteHost.RunHost to start up a PyAuto remote instance that you
  20   can connect to and automate using pyauto.RemoteProxy.
  21   """
  22   def __init__(self, host, *args, **kwargs):
  23     self.StartSocketServer(host)
  24
  25   def StartSocketServer(self, host):
  26     listening_socket = socket.socket()
  27     listening_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
  28     listening_socket.bind(host)
  29     listening_socket.listen(1)
  30     print 'Listening for incoming connections on port %d.' % host[1]
  31     self._socket, address = listening_socket.accept()
  32     print 'Accepted connection from %s:%d.' % address
  33
  34     while self.Connected():
  35       self._HandleRPC()
  36
  37   def StopSocketServer(self):
  38     if self._socket:
  39       try:
  40         self._socket.shutdown(socket.SHUT_RDWR)
  41         self._socket.close()
  42       except socket.error:
  43         pass
  44       self._socket = None
  45
  46   def Connected(self):
  47     return self._socket
  48
  49   def CreateTarget(self, target_class):
  50     """Creates an instance of the specified class to serve as the RPC target.
  51
  52     RPC calls can be made on the target.
  53     """
  54     self.target = target_class()
  55
  56   def _HandleRPC(self):
  57     """Receives a method call request over the socket and executes the method.
  58
  59     This method captures stdout and stderr for the duration of the method call,
  60     and sends those, the return value, and any thrown exceptions back to the
  61     RemoteProxy.
  62     """
  63     # Receive request.
  64     request = self._socket.recv(4096)
  65     if not request:
  66       self.StopSocketServer()
  67       return
  68     request = pickle.loads(request)
  69
  70     # Redirect output to strings.
  71     old_stdout = sys.stdout
  72     old_stderr = sys.stderr
  73     sys.stdout = stdout = cStringIO.StringIO()
  74     sys.stderr = stderr = cStringIO.StringIO()
  75
  76     # Make requested method call.
  77     result = None
  78     exception = None
  79     try:
  80       if getattr(self, request[0], None):
  81         result = getattr(self, request[0])(*request[1], **request[2])
  82       else:
  83         result = getattr(self.target, request[0])(*request[1], **request[2])
  84     except BaseException, e:
  85       exception = (e.__class__.__name__, str(e))
  86
  87     # Put output back to the way it was before.
  88     sys.stdout = old_stdout
  89     sys.stderr = old_stderr
  90
  91     # Package up and send the result of the method call.
  92     response = pickle.dumps((result, stdout.getvalue(), stderr.getvalue(),
  93                              exception))
  94     if self._socket.send(response) != len(response):
  95       self.StopSocketServer()
  96
  97
  98 if __name__ == '__main__':
  99   pyauto_suite = pyauto.PyUITestSuite(sys.argv)
 100   RemoteHost(('', 7410))
 101   del pyauto_suite