cpython/Lib/idlelib/rpc.py

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"""RPC Implementation, originally written for the Python Idle IDE
For security reasons, GvR requested that Idle's Python execution server process
connect to the Idle process, which listens for the connection. Since Idle has
only one client per server, this was not a limitation.
+---------------------------------+ +-------------+
| socketserver.BaseRequestHandler | | SocketIO |
+---------------------------------+ +-------------+
^ | register() |
| | unregister()|
| +-------------+
| ^ ^
| | |
| + -------------------+ |
| | |
+-------------------------+ +-----------------+
| RPCHandler | | RPCClient |
| [attribute of RPCServer]| | |
+-------------------------+ +-----------------+
The RPCServer handler class is expected to provide register/unregister methods.
RPCHandler inherits the mix-in class SocketIO, which provides these methods.
See the Idle run.main() docstring for further information on how this was
accomplished in Idle.
"""
import sys
import os
import io
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import socket
import select
import socketserver
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import struct
import pickle
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import threading
import queue
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import traceback
import copyreg
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import types
import marshal
import builtins
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def unpickle_code(ms):
co = marshal.loads(ms)
assert isinstance(co, types.CodeType)
return co
def pickle_code(co):
assert isinstance(co, types.CodeType)
ms = marshal.dumps(co)
return unpickle_code, (ms,)
def dumps(obj, protocol=None):
f = io.BytesIO()
p = CodePickler(f, protocol)
p.dump(obj)
return f.getvalue()
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class CodePickler(pickle.Pickler):
dispatch_table = {types.CodeType: pickle_code}
dispatch_table.update(copyreg.dispatch_table)
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BUFSIZE = 8*1024
LOCALHOST = '127.0.0.1'
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class RPCServer(socketserver.TCPServer):
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def __init__(self, addr, handlerclass=None):
if handlerclass is None:
handlerclass = RPCHandler
socketserver.TCPServer.__init__(self, addr, handlerclass)
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def server_bind(self):
"Override TCPServer method, no bind() phase for connecting entity"
pass
def server_activate(self):
"""Override TCPServer method, connect() instead of listen()
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Due to the reversed connection, self.server_address is actually the
address of the Idle Client to which we are connecting.
"""
self.socket.connect(self.server_address)
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def get_request(self):
"Override TCPServer method, return already connected socket"
return self.socket, self.server_address
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def handle_error(self, request, client_address):
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"""Override TCPServer method
Error message goes to __stderr__. No error message if exiting
normally or socket raised EOF. Other exceptions not handled in
server code will cause os._exit.
"""
try:
raise
except SystemExit:
raise
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except:
erf = sys.__stderr__
print('\n' + '-'*40, file=erf)
print('Unhandled server exception!', file=erf)
print('Thread: %s' % threading.current_thread().name, file=erf)
print('Client Address: ', client_address, file=erf)
print('Request: ', repr(request), file=erf)
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traceback.print_exc(file=erf)
print('\n*** Unrecoverable, server exiting!', file=erf)
print('-'*40, file=erf)
os._exit(0)
#----------------- end class RPCServer --------------------
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objecttable = {}
request_queue = queue.Queue(0)
response_queue = queue.Queue(0)
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class SocketIO(object):
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nextseq = 0
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def __init__(self, sock, objtable=None, debugging=None):
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self.sockthread = threading.current_thread()
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if debugging is not None:
self.debugging = debugging
self.sock = sock
if objtable is None:
objtable = objecttable
self.objtable = objtable
self.responses = {}
self.cvars = {}
def close(self):
sock = self.sock
self.sock = None
if sock is not None:
sock.close()
def exithook(self):
"override for specific exit action"
os._exit(0)
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def debug(self, *args):
if not self.debugging:
return
s = self.location + " " + str(threading.current_thread().name)
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for a in args:
s = s + " " + str(a)
print(s, file=sys.__stderr__)
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def register(self, oid, object):
self.objtable[oid] = object
def unregister(self, oid):
try:
del self.objtable[oid]
except KeyError:
pass
def localcall(self, seq, request):
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self.debug("localcall:", request)
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try:
how, (oid, methodname, args, kwargs) = request
except TypeError:
return ("ERROR", "Bad request format")
if oid not in self.objtable:
return ("ERROR", "Unknown object id: %r" % (oid,))
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obj = self.objtable[oid]
if methodname == "__methods__":
methods = {}
_getmethods(obj, methods)
return ("OK", methods)
if methodname == "__attributes__":
attributes = {}
_getattributes(obj, attributes)
return ("OK", attributes)
if not hasattr(obj, methodname):
return ("ERROR", "Unsupported method name: %r" % (methodname,))
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method = getattr(obj, methodname)
try:
if how == 'CALL':
ret = method(*args, **kwargs)
if isinstance(ret, RemoteObject):
ret = remoteref(ret)
return ("OK", ret)
elif how == 'QUEUE':
request_queue.put((seq, (method, args, kwargs)))
return("QUEUED", None)
else:
return ("ERROR", "Unsupported message type: %s" % how)
except SystemExit:
raise
except KeyboardInterrupt:
raise
except OSError:
raise
except Exception as ex:
return ("CALLEXC", ex)
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except:
msg = "*** Internal Error: rpc.py:SocketIO.localcall()\n\n"\
" Object: %s \n Method: %s \n Args: %s\n"
print(msg % (oid, method, args), file=sys.__stderr__)
traceback.print_exc(file=sys.__stderr__)
return ("EXCEPTION", None)
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def remotecall(self, oid, methodname, args, kwargs):
self.debug("remotecall:asynccall: ", oid, methodname)
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seq = self.asynccall(oid, methodname, args, kwargs)
return self.asyncreturn(seq)
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def remotequeue(self, oid, methodname, args, kwargs):
self.debug("remotequeue:asyncqueue: ", oid, methodname)
seq = self.asyncqueue(oid, methodname, args, kwargs)
return self.asyncreturn(seq)
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def asynccall(self, oid, methodname, args, kwargs):
request = ("CALL", (oid, methodname, args, kwargs))
seq = self.newseq()
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if threading.current_thread() != self.sockthread:
cvar = threading.Condition()
self.cvars[seq] = cvar
self.debug(("asynccall:%d:" % seq), oid, methodname, args, kwargs)
self.putmessage((seq, request))
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return seq
def asyncqueue(self, oid, methodname, args, kwargs):
request = ("QUEUE", (oid, methodname, args, kwargs))
seq = self.newseq()
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if threading.current_thread() != self.sockthread:
cvar = threading.Condition()
self.cvars[seq] = cvar
self.debug(("asyncqueue:%d:" % seq), oid, methodname, args, kwargs)
self.putmessage((seq, request))
return seq
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def asyncreturn(self, seq):
self.debug("asyncreturn:%d:call getresponse(): " % seq)
response = self.getresponse(seq, wait=0.05)
self.debug(("asyncreturn:%d:response: " % seq), response)
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return self.decoderesponse(response)
def decoderesponse(self, response):
how, what = response
if how == "OK":
return what
if how == "QUEUED":
return None
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if how == "EXCEPTION":
self.debug("decoderesponse: EXCEPTION")
return None
if how == "EOF":
self.debug("decoderesponse: EOF")
self.decode_interrupthook()
return None
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if how == "ERROR":
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self.debug("decoderesponse: Internal ERROR:", what)
raise RuntimeError(what)
if how == "CALLEXC":
self.debug("decoderesponse: Call Exception:", what)
raise what
raise SystemError(how, what)
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def decode_interrupthook(self):
""
raise EOFError
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def mainloop(self):
"""Listen on socket until I/O not ready or EOF
pollresponse() will loop looking for seq number None, which
never comes, and exit on EOFError.
"""
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try:
self.getresponse(myseq=None, wait=0.05)
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except EOFError:
self.debug("mainloop:return")
return
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def getresponse(self, myseq, wait):
response = self._getresponse(myseq, wait)
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if response is not None:
how, what = response
if how == "OK":
response = how, self._proxify(what)
return response
def _proxify(self, obj):
if isinstance(obj, RemoteProxy):
return RPCProxy(self, obj.oid)
if isinstance(obj, list):
return list(map(self._proxify, obj))
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# XXX Check for other types -- not currently needed
return obj
def _getresponse(self, myseq, wait):
self.debug("_getresponse:myseq:", myseq)
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if threading.current_thread() is self.sockthread:
# this thread does all reading of requests or responses
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while 1:
response = self.pollresponse(myseq, wait)
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if response is not None:
return response
else:
# wait for notification from socket handling thread
cvar = self.cvars[myseq]
cvar.acquire()
while myseq not in self.responses:
cvar.wait()
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response = self.responses[myseq]
self.debug("_getresponse:%s: thread woke up: response: %s" %
(myseq, response))
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del self.responses[myseq]
del self.cvars[myseq]
cvar.release()
return response
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def newseq(self):
self.nextseq = seq = self.nextseq + 2
return seq
def putmessage(self, message):
self.debug("putmessage:%d:" % message[0])
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try:
s = dumps(message)
except pickle.PicklingError:
print("Cannot pickle:", repr(message), file=sys.__stderr__)
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raise
s = struct.pack("<i", len(s)) + s
while len(s) > 0:
try:
r, w, x = select.select([], [self.sock], [])
n = self.sock.send(s[:BUFSIZE])
except (AttributeError, TypeError):
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raise OSError("socket no longer exists")
s = s[n:]
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buff = b''
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bufneed = 4
bufstate = 0 # meaning: 0 => reading count; 1 => reading data
def pollpacket(self, wait):
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self._stage0()
if len(self.buff) < self.bufneed:
r, w, x = select.select([self.sock.fileno()], [], [], wait)
if len(r) == 0:
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return None
try:
s = self.sock.recv(BUFSIZE)
except OSError:
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raise EOFError
if len(s) == 0:
raise EOFError
self.buff += s
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self._stage0()
return self._stage1()
def _stage0(self):
if self.bufstate == 0 and len(self.buff) >= 4:
s = self.buff[:4]
self.buff = self.buff[4:]
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self.bufneed = struct.unpack("<i", s)[0]
self.bufstate = 1
def _stage1(self):
if self.bufstate == 1 and len(self.buff) >= self.bufneed:
packet = self.buff[:self.bufneed]
self.buff = self.buff[self.bufneed:]
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self.bufneed = 4
self.bufstate = 0
return packet
def pollmessage(self, wait):
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packet = self.pollpacket(wait)
if packet is None:
return None
try:
message = pickle.loads(packet)
except pickle.UnpicklingError:
print("-----------------------", file=sys.__stderr__)
print("cannot unpickle packet:", repr(packet), file=sys.__stderr__)
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traceback.print_stack(file=sys.__stderr__)
print("-----------------------", file=sys.__stderr__)
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raise
return message
def pollresponse(self, myseq, wait):
"""Handle messages received on the socket.
Some messages received may be asynchronous 'call' or 'queue' requests,
and some may be responses for other threads.
'call' requests are passed to self.localcall() with the expectation of
immediate execution, during which time the socket is not serviced.
'queue' requests are used for tasks (which may block or hang) to be
processed in a different thread. These requests are fed into
request_queue by self.localcall(). Responses to queued requests are
taken from response_queue and sent across the link with the associated
sequence numbers. Messages in the queues are (sequence_number,
request/response) tuples and code using this module removing messages
from the request_queue is responsible for returning the correct
sequence number in the response_queue.
pollresponse() will loop until a response message with the myseq
sequence number is received, and will save other responses in
self.responses and notify the owning thread.
"""
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while 1:
# send queued response if there is one available
try:
qmsg = response_queue.get(0)
except queue.Empty:
pass
else:
seq, response = qmsg
message = (seq, ('OK', response))
self.putmessage(message)
# poll for message on link
try:
message = self.pollmessage(wait)
if message is None: # socket not ready
return None
except EOFError:
self.handle_EOF()
return None
except AttributeError:
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return None
seq, resq = message
how = resq[0]
self.debug("pollresponse:%d:myseq:%s" % (seq, myseq))
# process or queue a request
if how in ("CALL", "QUEUE"):
self.debug("pollresponse:%d:localcall:call:" % seq)
response = self.localcall(seq, resq)
self.debug("pollresponse:%d:localcall:response:%s"
% (seq, response))
if how == "CALL":
self.putmessage((seq, response))
elif how == "QUEUE":
# don't acknowledge the 'queue' request!
pass
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continue
# return if completed message transaction
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elif seq == myseq:
return resq
# must be a response for a different thread:
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else:
cv = self.cvars.get(seq, None)
# response involving unknown sequence number is discarded,
# probably intended for prior incarnation of server
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if cv is not None:
cv.acquire()
self.responses[seq] = resq
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cv.notify()
cv.release()
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continue
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def handle_EOF(self):
"action taken upon link being closed by peer"
self.EOFhook()
self.debug("handle_EOF")
for key in self.cvars:
cv = self.cvars[key]
cv.acquire()
self.responses[key] = ('EOF', None)
cv.notify()
cv.release()
# call our (possibly overridden) exit function
self.exithook()
def EOFhook(self):
"Classes using rpc client/server can override to augment EOF action"
pass
#----------------- end class SocketIO --------------------
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class RemoteObject(object):
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# Token mix-in class
pass
def remoteref(obj):
oid = id(obj)
objecttable[oid] = obj
return RemoteProxy(oid)
class RemoteProxy(object):
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def __init__(self, oid):
self.oid = oid
class RPCHandler(socketserver.BaseRequestHandler, SocketIO):
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debugging = False
location = "#S" # Server
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def __init__(self, sock, addr, svr):
svr.current_handler = self ## cgt xxx
SocketIO.__init__(self, sock)
socketserver.BaseRequestHandler.__init__(self, sock, addr, svr)
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def handle(self):
"handle() method required by socketserver"
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self.mainloop()
def get_remote_proxy(self, oid):
return RPCProxy(self, oid)
class RPCClient(SocketIO):
debugging = False
location = "#C" # Client
nextseq = 1 # Requests coming from the client are odd numbered
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def __init__(self, address, family=socket.AF_INET, type=socket.SOCK_STREAM):
self.listening_sock = socket.socket(family, type)
self.listening_sock.bind(address)
self.listening_sock.listen(1)
def accept(self):
working_sock, address = self.listening_sock.accept()
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if self.debugging:
print("****** Connection request from ", address, file=sys.__stderr__)
if address[0] == LOCALHOST:
SocketIO.__init__(self, working_sock)
else:
print("** Invalid host: ", address, file=sys.__stderr__)
raise OSError
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def get_remote_proxy(self, oid):
return RPCProxy(self, oid)
class RPCProxy(object):
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__methods = None
__attributes = None
def __init__(self, sockio, oid):
self.sockio = sockio
self.oid = oid
def __getattr__(self, name):
if self.__methods is None:
self.__getmethods()
if self.__methods.get(name):
return MethodProxy(self.sockio, self.oid, name)
if self.__attributes is None:
self.__getattributes()
if name in self.__attributes:
value = self.sockio.remotecall(self.oid, '__getattribute__',
(name,), {})
return value
else:
raise AttributeError(name)
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def __getattributes(self):
self.__attributes = self.sockio.remotecall(self.oid,
"__attributes__", (), {})
def __getmethods(self):
self.__methods = self.sockio.remotecall(self.oid,
"__methods__", (), {})
def _getmethods(obj, methods):
# Helper to get a list of methods from an object
# Adds names to dictionary argument 'methods'
for name in dir(obj):
attr = getattr(obj, name)
if callable(attr):
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methods[name] = 1
if isinstance(obj, type):
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for super in obj.__bases__:
_getmethods(super, methods)
def _getattributes(obj, attributes):
for name in dir(obj):
attr = getattr(obj, name)
if not callable(attr):
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attributes[name] = 1
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class MethodProxy(object):
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def __init__(self, sockio, oid, name):
self.sockio = sockio
self.oid = oid
self.name = name
def __call__(self, *args, **kwargs):
value = self.sockio.remotecall(self.oid, self.name, args, kwargs)
return value
# XXX KBK 09Sep03 We need a proper unit test for this module. Previously
Merged revisions 74277,74321,74323,74326,74355,74465,74467,74488,74492,74513,74531,74549,74553,74625,74632,74643-74644,74647,74652,74666,74671,74727,74739 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r74277 | sean.reifschneider | 2009-08-01 18:54:55 -0500 (Sat, 01 Aug 2009) | 3 lines - Issue #6624: yArg_ParseTuple with "s" format when parsing argument with NUL: Bogus TypeError detail string. ........ r74321 | guilherme.polo | 2009-08-05 11:51:41 -0500 (Wed, 05 Aug 2009) | 1 line Easier reference to find (at least while svn continues being used). ........ r74323 | guilherme.polo | 2009-08-05 18:48:26 -0500 (Wed, 05 Aug 2009) | 1 line Typo. ........ r74326 | jesse.noller | 2009-08-05 21:05:56 -0500 (Wed, 05 Aug 2009) | 1 line Fix issue 4660: spurious task_done errors in multiprocessing, remove doc note for from_address ........ r74355 | gregory.p.smith | 2009-08-12 12:02:37 -0500 (Wed, 12 Aug 2009) | 2 lines comment typo fix ........ r74465 | vinay.sajip | 2009-08-15 18:23:12 -0500 (Sat, 15 Aug 2009) | 1 line Added section on logging to one file from multiple processes. ........ r74467 | vinay.sajip | 2009-08-15 18:34:47 -0500 (Sat, 15 Aug 2009) | 1 line Refined section on logging to one file from multiple processes. ........ r74488 | vinay.sajip | 2009-08-17 08:14:37 -0500 (Mon, 17 Aug 2009) | 1 line Further refined section on logging to one file from multiple processes. ........ r74492 | r.david.murray | 2009-08-17 14:26:49 -0500 (Mon, 17 Aug 2009) | 2 lines Issue 6685: 'toupper' -> 'upper' in cgi doc example explanation. ........ r74513 | skip.montanaro | 2009-08-18 09:37:52 -0500 (Tue, 18 Aug 2009) | 1 line missing module ref (issue6723) ........ r74531 | vinay.sajip | 2009-08-20 17:04:32 -0500 (Thu, 20 Aug 2009) | 1 line Added section on exceptions raised during logging. ........ r74549 | benjamin.peterson | 2009-08-24 12:42:36 -0500 (Mon, 24 Aug 2009) | 1 line fix pdf building by teaching latex the right encoding package ........ r74553 | r.david.murray | 2009-08-26 20:04:59 -0500 (Wed, 26 Aug 2009) | 2 lines Remove leftover text from end of sentence. ........ r74625 | benjamin.peterson | 2009-09-01 17:27:57 -0500 (Tue, 01 Sep 2009) | 1 line remove the check that classmethod's argument is a callable ........ r74632 | georg.brandl | 2009-09-03 02:27:26 -0500 (Thu, 03 Sep 2009) | 1 line #6828: fix wrongly highlighted blocks. ........ r74643 | georg.brandl | 2009-09-04 01:59:20 -0500 (Fri, 04 Sep 2009) | 2 lines Issue #2666: Handle BROWSER environment variable properly for unknown browser names in the webbrowser module. ........ r74644 | georg.brandl | 2009-09-04 02:55:14 -0500 (Fri, 04 Sep 2009) | 1 line #5047: remove Monterey support from configure. ........ r74647 | georg.brandl | 2009-09-04 03:17:04 -0500 (Fri, 04 Sep 2009) | 2 lines Issue #5275: In Cookie's Cookie.load(), properly handle non-string arguments as documented. ........ r74652 | georg.brandl | 2009-09-04 06:25:37 -0500 (Fri, 04 Sep 2009) | 1 line #6756: add some info about the "acct" parameter. ........ r74666 | georg.brandl | 2009-09-05 04:04:09 -0500 (Sat, 05 Sep 2009) | 1 line #6841: remove duplicated word. ........ r74671 | georg.brandl | 2009-09-05 11:47:17 -0500 (Sat, 05 Sep 2009) | 1 line #6843: add link from filterwarnings to where the meaning of the arguments is covered. ........ r74727 | benjamin.peterson | 2009-09-08 18:04:22 -0500 (Tue, 08 Sep 2009) | 1 line #6865 fix ref counting in initialization of pwd module ........ r74739 | georg.brandl | 2009-09-11 02:55:20 -0500 (Fri, 11 Sep 2009) | 1 line Move function back to its section. ........
2009-09-11 19:24:02 -03:00
# existing test code was removed at Rev 1.27 (r34098).
def displayhook(value):
"""Override standard display hook to use non-locale encoding"""
if value is None:
return
# Set '_' to None to avoid recursion
builtins._ = None
text = repr(value)
try:
sys.stdout.write(text)
except UnicodeEncodeError:
# let's use ascii while utf8-bmp codec doesn't present
encoding = 'ascii'
bytes = text.encode(encoding, 'backslashreplace')
text = bytes.decode(encoding, 'strict')
sys.stdout.write(text)
sys.stdout.write("\n")
builtins._ = value