• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1# Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
2# Use of this source code is governed by a BSD-style license that can be
3# found in the LICENSE file.
4
5import httplib
6import socket
7import time
8import xmlrpclib
9
10from autotest_lib.client.cros.faft.config import Config as ClientConfig
11from autotest_lib.server import autotest
12
13
14class _Method(object):
15    """Class to save the name of the RPC method instead of the real object.
16
17    It keeps the name of the RPC method locally first such that the RPC method
18    can be evalulated to a real object while it is called. Its purpose is to
19    refer to the latest RPC proxy as the original previous-saved RPC proxy may
20    be lost due to reboot.
21
22    The call_method is the method which does refer to the latest RPC proxy.
23    """
24    def __init__(self, call_method, name):
25        self.__call_method = call_method
26        self.__name = name
27
28    def __getattr__(self, name):
29        # Support a nested method.
30        return _Method(self.__call_method, "%s.%s" % (self.__name, name))
31
32    def __call__(self, *args, **dargs):
33        return self.__call_method(self.__name, *args, **dargs)
34
35    def __str__(self):
36        """Return a description of the method object"""
37        return "%s('%s')" % (self.__class__.__name__, self.__name)
38
39    def __repr__(self):
40        """Return a description of the method object"""
41        return "<%s '%s'>" % (self.__class__.__name__, self.__name)
42
43
44class RPCProxy(object):
45    """Proxy to the FAFTClient RPC server on DUT.
46
47    It acts as a proxy to the FAFTClient on DUT. It is smart enough to:
48     - postpone the RPC connection to the first class method call;
49     - reconnect to the RPC server in case connection lost, e.g. reboot;
50     - always call the latest RPC proxy object.
51
52     @ivar _client: the ssh host object
53     @type host: autotest_lib.server.hosts.abstract_ssh.AbstractSSHHost
54     @ivar _faft_client: the real serverproxy to use for calls
55     @type _faft_client: xmlrpclib.ServerProxy
56    """
57    _client_config = ClientConfig()
58
59    def __init__(self, host):
60        """Constructor.
61
62        @param host: The host object, passed via the test control file.
63        """
64        self._client = host
65        self._faft_client = None
66
67    def __del__(self):
68        self.disconnect()
69
70    def __getattr__(self, name):
71        """Return a _Method object only, not its real object."""
72        return _Method(self.__call_faft_client, name)
73
74    def __call_faft_client(self, name, *args, **dargs):
75        """Make the call on the latest RPC proxy object.
76
77        This method gets the internal method of the RPC proxy and calls it.
78
79        @param name: Name of the RPC method, a nested method supported.
80        @param args: The rest of arguments.
81        @param dargs: The rest of dict-type arguments.
82        @return: The return value of the FAFTClient RPC method.
83        """
84        if self._faft_client is None:
85            self.connect()
86        try:
87            return getattr(self._faft_client, name)(*args, **dargs)
88        except (socket.error,
89                httplib.BadStatusLine,
90                xmlrpclib.ProtocolError):
91            # Reconnect the RPC server in case connection lost, e.g. reboot.
92            self.connect()
93            # Try again.
94            return getattr(self._faft_client, name)(*args, **dargs)
95
96    def connect(self):
97        """Connect the RPC server."""
98        # Make sure Autotest dependency is there.
99        autotest.Autotest(self._client).install()
100        self._faft_client = self._client.rpc_server_tracker.xmlrpc_connect(
101                self._client_config.rpc_command,
102                self._client_config.rpc_port,
103                command_name=self._client_config.rpc_command_short,
104                ready_test_name=self._client_config.rpc_ready_call,
105                timeout_seconds=self._client_config.rpc_timeout,
106                logfile="%s.%s" % (self._client_config.rpc_logfile,
107                                   time.time())
108                )
109
110    def disconnect(self):
111        """Disconnect the RPC server."""
112        self._client.rpc_server_tracker.disconnect(self._client_config.rpc_port)
113        self._faft_client = None
114
115    def __str__(self):
116        """Return a description of the proxy object"""
117        return '%s(%s)' % (self.__class__.__name__, self._client)
118
119    def __repr__(self):
120        """Return a description of the proxy object"""
121        return "<%s '%s'>" % (self.__class__.__name__, self._client.hostname)
122