Source Code for Module ganeti.metad

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29   
30   
31  """Module for the Metad protocol 
32   
33  """ 
34   
35  import logging 
36  import random 
37  import time 
38   
39  from ganeti import constants 
40  from ganeti import errors 
41  import ganeti.rpc.client as cl 
42  from ganeti.rpc.transport import Transport 
43  from ganeti.rpc import errors 
44   
45   
46  # If the metadata daemon is disabled, there is no stub generated for it. 
47  # So import the module and define the client class only if enabled, otherwise 
48  # just generate an empty placeholder class. 
49  if constants.ENABLE_METAD: 
50    import ganeti.rpc.stub.metad as stub 
51   
52 -  class Client(cl.AbstractStubClient, stub.ClientRpcStub): 
53      """High-level Metad client implementation. 
54   
55      This uses a backing Transport-like class on top of which it 
56      implements data serialization/deserialization. 
57   
58      """ 
59 -    def __init__(self, timeouts=None, transport=Transport): 
60        """Constructor for the Client class. 
61   
62        Arguments are the same as for L{AbstractClient}. 
63   
64        """ 
65        cl.AbstractStubClient.__init__(self, timeouts, transport) 
66        stub.ClientRpcStub.__init__(self) 
67   
68        retries = 12 
69        for try_no in range(0, retries): 
70          try: 
71            self._InitTransport() 
72            return 
73          except errors.TimeoutError: 
74            logging.debug("Timout trying to connect to MetaD") 
75            if try_no == retries - 1: 
76              raise 
77            logging.debug("Will retry") 
78            time.sleep(try_no * 10 + 10 * random.random()) 
79   
80 -    def _InitTransport(self): 
81        """(Re)initialize the transport if needed. 
82   
83        """ 
84        if self.transport is None: 
85          self.transport = self.transport_class(self._GetAddress(), 
86                                                timeouts=self.timeouts, 
87                                                allow_non_master=True) 
88   
89  else: 
90 -  class Client(object): 
91      """An empty client representation that just throws an exception. 
92   
93      """ 
94 -    def __init__(self, _timeouts=None, _transport=None): 
95        raise errors.ProgrammerError("The metadata deamon is disabled, yet" 
96                                     " the client has been called") 
97