"""RPC Client module."""
import sys
import socket
import pickle
import builtins
import os
# Default verbosity (0 = silent, 1 = print connections, 2 = print requests too)
VERBOSE = 1
class Client:
"""RPC Client class. No need to derive a class -- it's fully generic."""
def __init__(self, address, verbose = VERBOSE):
self._pre_init(address, verbose)
self._post_init()
def _pre_init(self, address, verbose = VERBOSE):
if type(address) == type(0):
address = ('', address)
self._address = address
self._verbose = verbose
if self._verbose: print("Connecting to %s ..." % repr(address))
self._socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self._socket.connect(address)
if self._verbose: print("Connected.")
self._lastid = 0 # Last id for which a reply has been received
self._nextid = 1 # Id of next request
self._replies = {} # Unprocessed replies
self._rf = self._socket.makefile('r')
self._wf = self._socket.makefile('w')
def _post_init(self):
self._methods = self._call('.methods')
def __del__(self):
self._close()
def _close(self):
if self._rf: self._rf.close()
self._rf = None
if self._wf: self._wf.close()
self._wf = None
if self._socket: self._socket.close()
self._socket = None
def __getattr__(self, name):
if name in self._methods:
method = _stub(self, name)
setattr(self, name, method) # XXX circular reference
return method
raise AttributeError(name)
def _setverbose(self, verbose):
self._verbose = verbose
def _call(self, name, *args):
return self._vcall(name, args)
def _vcall(self, name, args):
return self._recv(self._vsend(name, args))
def _send(self, name, *args):
return self._vsend(name, args)
def _send_noreply(self, name, *args):
return self._vsend(name, args, 0)
def _vsend_noreply(self, name, args):
return self._vsend(name, args, 0)
def _vsend(self, name, args, wantreply = 1):
id = self._nextid
self._nextid = id+1
if not wantreply: id = -id
request = (name, args, id)
if self._verbose > 1: print("sending request: %s" % repr(request))
wp = pickle.Pickler(self._wf)
wp.dump(request)
return id
def _recv(self, id):
exception, value, rid = self._vrecv(id)
if rid != id:
raise RuntimeError("request/reply id mismatch: %d/%d" % (id, rid))
if exception is None:
return value
x = exception
if hasattr(builtins, exception):
x = getattr(builtins, exception)
elif exception in ('posix.error', 'mac.error'):
x = os.error
if x == exception:
exception = x
raise exception(value)
def _vrecv(self, id):
self._flush()
if id in self._replies:
if self._verbose > 1: print("retrieving previous reply, id = %d" % id)
reply = self._replies[id]
del self._replies[id]
return reply
aid = abs(id)
while 1:
if self._verbose > 1: print("waiting for reply, id = %d" % id)
rp = pickle.Unpickler(self._rf)
reply = rp.load()
del rp
if self._verbose > 1: print("got reply: %s" % repr(reply))
rid = reply[2]
arid = abs(rid)
if arid == aid:
if self._verbose > 1: print("got it")
return reply
self._replies[rid] = reply
if arid > aid:
if self._verbose > 1: print("got higher id, assume all ok")
return (None, None, id)
def _flush(self):
self._wf.flush()
from security import Security
class SecureClient(Client, Security):
def __init__(self, *args):
self._pre_init(*args)
Security.__init__(self)
self._wf.flush()
line = self._rf.readline()
challenge = int(line.strip())
response = self._encode_challenge(challenge)
line = repr(int(response))
if line[-1] in 'Ll': line = line[:-1]
self._wf.write(line + '\n')
self._wf.flush()
self._post_init()
class _stub:
"""Helper class for Client -- each instance serves as a method of the client."""
def __init__(self, client, name):
self._client = client
self._name = name
def __call__(self, *args):
return self._client._vcall(self._name, args)
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