572 lines
18 KiB
Python
572 lines
18 KiB
Python
"""RPC Implemention, 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
|
|
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 socket
|
|
import select
|
|
import SocketServer
|
|
import struct
|
|
import cPickle as pickle
|
|
import threading
|
|
import traceback
|
|
import copy_reg
|
|
import types
|
|
import marshal
|
|
|
|
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,)
|
|
|
|
# XXX KBK 24Aug02 function pickling capability not used in Idle
|
|
# def unpickle_function(ms):
|
|
# return ms
|
|
|
|
# def pickle_function(fn):
|
|
# assert isinstance(fn, type.FunctionType)
|
|
# return `fn`
|
|
|
|
copy_reg.pickle(types.CodeType, pickle_code, unpickle_code)
|
|
# copy_reg.pickle(types.FunctionType, pickle_function, unpickle_function)
|
|
|
|
BUFSIZE = 8*1024
|
|
|
|
class RPCServer(SocketServer.TCPServer):
|
|
|
|
def __init__(self, addr, handlerclass=None):
|
|
if handlerclass is None:
|
|
handlerclass = RPCHandler
|
|
SocketServer.TCPServer.__init__(self, addr, handlerclass)
|
|
|
|
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()
|
|
|
|
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)
|
|
|
|
def get_request(self):
|
|
"Override TCPServer method, return already connected socket"
|
|
return self.socket, self.server_address
|
|
|
|
objecttable = {}
|
|
|
|
class SocketIO:
|
|
|
|
nextseq = 0
|
|
|
|
def __init__(self, sock, objtable=None, debugging=None):
|
|
self.mainthread = threading.currentThread()
|
|
if debugging is not None:
|
|
self.debugging = debugging
|
|
self.sock = sock
|
|
if objtable is None:
|
|
objtable = objecttable
|
|
self.objtable = objtable
|
|
self.statelock = threading.Lock()
|
|
self.responses = {}
|
|
self.cvars = {}
|
|
|
|
def close(self):
|
|
sock = self.sock
|
|
self.sock = None
|
|
if sock is not None:
|
|
sock.close()
|
|
|
|
def debug(self, *args):
|
|
if not self.debugging:
|
|
return
|
|
s = self.location + " " + str(threading.currentThread().getName())
|
|
for a in args:
|
|
s = s + " " + str(a)
|
|
print>>sys.__stderr__, s
|
|
|
|
def register(self, oid, object):
|
|
self.objtable[oid] = object
|
|
|
|
def unregister(self, oid):
|
|
try:
|
|
del self.objtable[oid]
|
|
except KeyError:
|
|
pass
|
|
|
|
def localcall(self, request):
|
|
self.debug("localcall:", request)
|
|
try:
|
|
how, (oid, methodname, args, kwargs) = request
|
|
except TypeError:
|
|
return ("ERROR", "Bad request format")
|
|
assert how == "call"
|
|
if not self.objtable.has_key(oid):
|
|
return ("ERROR", "Unknown object id: %s" % `oid`)
|
|
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: %s" % `methodname`)
|
|
method = getattr(obj, methodname)
|
|
try:
|
|
ret = method(*args, **kwargs)
|
|
if isinstance(ret, RemoteObject):
|
|
ret = remoteref(ret)
|
|
return ("OK", ret)
|
|
except:
|
|
##traceback.print_exc(file=sys.__stderr__)
|
|
typ, val, tb = info = sys.exc_info()
|
|
sys.last_type, sys.last_value, sys.last_traceback = info
|
|
if isinstance(typ, type(Exception)):
|
|
# Class exception
|
|
mod = typ.__module__
|
|
name = typ.__name__
|
|
if issubclass(typ, Exception):
|
|
args = val.args
|
|
else:
|
|
args = (str(val),)
|
|
else:
|
|
# User string exception
|
|
mod = None
|
|
name = typ
|
|
if val is None: val = ''
|
|
args = str(val)
|
|
tb = traceback.extract_tb(tb)
|
|
self.debug("localcall:EXCEPTION: ", mod, name, args, tb)
|
|
return ("EXCEPTION", (mod, name, args, tb))
|
|
|
|
def remotecall(self, oid, methodname, args, kwargs):
|
|
self.debug("calling asynccall via remotecall")
|
|
seq = self.asynccall(oid, methodname, args, kwargs)
|
|
return self.asyncreturn(seq)
|
|
|
|
def asynccall(self, oid, methodname, args, kwargs):
|
|
request = ("call", (oid, methodname, args, kwargs))
|
|
seq = self.newseq()
|
|
self.debug(("asynccall:%d:" % seq), oid, methodname, args, kwargs)
|
|
self.putmessage((seq, request))
|
|
return seq
|
|
|
|
def asyncreturn(self, seq):
|
|
self.debug("asyncreturn:%d:call getresponse(): " % seq)
|
|
response = self.getresponse(seq)
|
|
self.debug(("asyncreturn:%d:response: " % seq), response)
|
|
return self.decoderesponse(response)
|
|
|
|
def decoderesponse(self, response):
|
|
how, what = response
|
|
if how == "OK":
|
|
return what
|
|
if how == "EXCEPTION":
|
|
self.debug("decoderesponse: EXCEPTION:", what)
|
|
mod, name, args, tb = what
|
|
self.traceback = tb
|
|
if mod: # not string exception
|
|
try:
|
|
__import__(mod)
|
|
module = sys.modules[mod]
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
try:
|
|
cls = getattr(module, name)
|
|
except AttributeError:
|
|
pass
|
|
else:
|
|
# instantiate a built-in exception object and raise it
|
|
raise getattr(__import__(mod), name)(*args)
|
|
name = mod + "." + name
|
|
# do the best we can:
|
|
raise name, args
|
|
if how == "ERROR":
|
|
self.debug("decoderesponse: Internal ERROR:", what)
|
|
raise RuntimeError, what
|
|
raise SystemError, (how, what)
|
|
|
|
def mainloop(self):
|
|
"""Listen on socket until I/O not ready or EOF
|
|
|
|
pollpacket() will loop looking for seq number None, which never
|
|
comes. The loop will exit when self.ioready() returns 0.
|
|
|
|
"""
|
|
try:
|
|
self.getresponse(None)
|
|
except EOFError:
|
|
pass
|
|
|
|
def getresponse(self, myseq):
|
|
response = self._getresponse(myseq)
|
|
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, types.ListType):
|
|
return map(self._proxify, obj)
|
|
# XXX Check for other types -- not currently needed
|
|
return obj
|
|
|
|
def _getresponse(self, myseq):
|
|
self.debug("_getresponse:myseq:", myseq)
|
|
if threading.currentThread() is self.mainthread:
|
|
# Main thread: does all reading of requests or responses
|
|
# Loop here until there is message traffic on the socket
|
|
while 1:
|
|
response = self.pollresponse(myseq, None)
|
|
if response is not None:
|
|
return response
|
|
else:
|
|
# Auxiliary thread: wait for notification from main thread
|
|
cvar = threading.Condition(self.statelock)
|
|
self.statelock.acquire()
|
|
self.cvars[myseq] = cvar
|
|
while not self.responses.has_key(myseq):
|
|
cvar.wait()
|
|
response = self.responses[myseq]
|
|
del self.responses[myseq]
|
|
del self.cvars[myseq]
|
|
self.statelock.release()
|
|
return response # might be None
|
|
|
|
def newseq(self):
|
|
self.nextseq = seq = self.nextseq + 2
|
|
return seq
|
|
|
|
def putmessage(self, message):
|
|
self.debug("putmessage:%d:" % message[0])
|
|
try:
|
|
s = pickle.dumps(message)
|
|
except:
|
|
print >>sys.__stderr__, "Cannot pickle:", `message`
|
|
raise
|
|
s = struct.pack("<i", len(s)) + s
|
|
while len(s) > 0:
|
|
n = self.sock.send(s)
|
|
s = s[n:]
|
|
|
|
def ioready(self, wait=0.0):
|
|
r, w, x = select.select([self.sock.fileno()], [], [], wait)
|
|
return len(r)
|
|
|
|
buffer = ""
|
|
bufneed = 4
|
|
bufstate = 0 # meaning: 0 => reading count; 1 => reading data
|
|
|
|
def pollpacket(self, wait=0.0):
|
|
self._stage0()
|
|
if len(self.buffer) < self.bufneed:
|
|
if not self.ioready(wait):
|
|
return None
|
|
try:
|
|
s = self.sock.recv(BUFSIZE)
|
|
except socket.error:
|
|
raise EOFError
|
|
if len(s) == 0:
|
|
raise EOFError
|
|
self.buffer += s
|
|
self._stage0()
|
|
return self._stage1()
|
|
|
|
def _stage0(self):
|
|
if self.bufstate == 0 and len(self.buffer) >= 4:
|
|
s = self.buffer[:4]
|
|
self.buffer = self.buffer[4:]
|
|
self.bufneed = struct.unpack("<i", s)[0]
|
|
self.bufstate = 1
|
|
|
|
def _stage1(self):
|
|
if self.bufstate == 1 and len(self.buffer) >= self.bufneed:
|
|
packet = self.buffer[:self.bufneed]
|
|
self.buffer = self.buffer[self.bufneed:]
|
|
self.bufneed = 4
|
|
self.bufstate = 0
|
|
return packet
|
|
|
|
def pollmessage(self, wait=0.0):
|
|
packet = self.pollpacket(wait)
|
|
if packet is None:
|
|
return None
|
|
try:
|
|
message = pickle.loads(packet)
|
|
except:
|
|
print >>sys.__stderr__, "-----------------------"
|
|
print >>sys.__stderr__, "cannot unpickle packet:", `packet`
|
|
traceback.print_stack(file=sys.__stderr__)
|
|
print >>sys.__stderr__, "-----------------------"
|
|
raise
|
|
return message
|
|
|
|
def pollresponse(self, myseq, wait=0.0):
|
|
"""Handle messages received on the socket.
|
|
|
|
Some messages received may be asynchronous 'call' commands, and
|
|
some may be responses intended for other threads.
|
|
|
|
Loop until message with myseq sequence number is received. Save others
|
|
in self.responses and notify the owning thread, except that 'call'
|
|
commands are handed off to localcall() and the response sent back
|
|
across the link with the appropriate sequence number.
|
|
|
|
"""
|
|
while 1:
|
|
message = self.pollmessage(wait)
|
|
if message is None: # socket not ready
|
|
return None
|
|
wait = 0.0
|
|
seq, resq = message
|
|
self.debug("pollresponse:%d:myseq:%s" % (seq, myseq))
|
|
if resq[0] == "call":
|
|
self.debug("pollresponse:%d:localcall:call:" % seq)
|
|
response = self.localcall(resq)
|
|
self.debug("pollresponse:%d:localcall:response:%s"
|
|
% (seq, response))
|
|
self.putmessage((seq, response))
|
|
continue
|
|
elif seq == myseq:
|
|
return resq
|
|
else:
|
|
self.statelock.acquire()
|
|
self.responses[seq] = resq
|
|
cv = self.cvars.get(seq)
|
|
if cv is not None:
|
|
cv.notify()
|
|
self.statelock.release()
|
|
continue
|
|
|
|
#----------------- end class SocketIO --------------------
|
|
|
|
class RemoteObject:
|
|
# Token mix-in class
|
|
pass
|
|
|
|
def remoteref(obj):
|
|
oid = id(obj)
|
|
objecttable[oid] = obj
|
|
return RemoteProxy(oid)
|
|
|
|
class RemoteProxy:
|
|
|
|
def __init__(self, oid):
|
|
self.oid = oid
|
|
|
|
class RPCHandler(SocketServer.BaseRequestHandler, SocketIO):
|
|
|
|
debugging = False
|
|
location = "#S" # Server
|
|
|
|
def __init__(self, sock, addr, svr):
|
|
svr.current_handler = self ## cgt xxx
|
|
SocketIO.__init__(self, sock)
|
|
SocketServer.BaseRequestHandler.__init__(self, sock, addr, svr)
|
|
|
|
def handle(self):
|
|
"handle() method required by SocketServer"
|
|
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
|
|
|
|
def __init__(self, address, family=socket.AF_INET, type=socket.SOCK_STREAM):
|
|
self.listening_sock = socket.socket(family, type)
|
|
self.listening_sock.setsockopt(socket.SOL_SOCKET,
|
|
socket.SO_REUSEADDR, 1)
|
|
self.listening_sock.bind(address)
|
|
self.listening_sock.listen(1)
|
|
|
|
def accept(self):
|
|
working_sock, address = self.listening_sock.accept()
|
|
if self.debugging:
|
|
print>>sys.__stderr__, "****** Connection request from ", address
|
|
if address[0] == '127.0.0.1':
|
|
SocketIO.__init__(self, working_sock)
|
|
else:
|
|
print>>sys.__stderr__, "** Invalid host: ", address
|
|
raise socket.error
|
|
|
|
def get_remote_proxy(self, oid):
|
|
return RPCProxy(self, oid)
|
|
|
|
class RPCProxy:
|
|
|
|
__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 not self.__attributes.has_key(name):
|
|
raise AttributeError, name
|
|
__getattr__.DebuggerStepThrough=1
|
|
|
|
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):
|
|
methods[name] = 1
|
|
if type(obj) == types.InstanceType:
|
|
_getmethods(obj.__class__, methods)
|
|
if type(obj) == types.ClassType:
|
|
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):
|
|
attributes[name] = 1
|
|
|
|
class MethodProxy:
|
|
|
|
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
|
|
|
|
#
|
|
# Self Test
|
|
#
|
|
|
|
def testServer(addr):
|
|
# XXX 25 Jul 02 KBK needs update to use rpc.py register/unregister methods
|
|
class RemotePerson:
|
|
def __init__(self,name):
|
|
self.name = name
|
|
def greet(self, name):
|
|
print "(someone called greet)"
|
|
print "Hello %s, I am %s." % (name, self.name)
|
|
print
|
|
def getName(self):
|
|
print "(someone called getName)"
|
|
print
|
|
return self.name
|
|
def greet_this_guy(self, name):
|
|
print "(someone called greet_this_guy)"
|
|
print "About to greet %s ..." % name
|
|
remote_guy = self.server.current_handler.get_remote_proxy(name)
|
|
remote_guy.greet("Thomas Edison")
|
|
print "Done."
|
|
print
|
|
|
|
person = RemotePerson("Thomas Edison")
|
|
svr = RPCServer(addr)
|
|
svr.register('thomas', person)
|
|
person.server = svr # only required if callbacks are used
|
|
|
|
# svr.serve_forever()
|
|
svr.handle_request() # process once only
|
|
|
|
def testClient(addr):
|
|
"demonstrates RPC Client"
|
|
# XXX 25 Jul 02 KBK needs update to use rpc.py register/unregister methods
|
|
import time
|
|
clt=RPCClient(addr)
|
|
thomas = clt.get_remote_proxy("thomas")
|
|
print "The remote person's name is ..."
|
|
print thomas.getName()
|
|
# print clt.remotecall("thomas", "getName", (), {})
|
|
print
|
|
time.sleep(1)
|
|
print "Getting remote thomas to say hi..."
|
|
thomas.greet("Alexander Bell")
|
|
#clt.remotecall("thomas","greet",("Alexander Bell",), {})
|
|
print "Done."
|
|
print
|
|
time.sleep(2)
|
|
# demonstrates remote server calling local instance
|
|
class LocalPerson:
|
|
def __init__(self,name):
|
|
self.name = name
|
|
def greet(self, name):
|
|
print "You've greeted me!"
|
|
def getName(self):
|
|
return self.name
|
|
person = LocalPerson("Alexander Bell")
|
|
clt.register("alexander",person)
|
|
thomas.greet_this_guy("alexander")
|
|
# clt.remotecall("thomas","greet_this_guy",("alexander",), {})
|
|
|
|
def test():
|
|
addr=("localhost",8833)
|
|
if len(sys.argv) == 2:
|
|
if sys.argv[1]=='-server':
|
|
testServer(addr)
|
|
return
|
|
testClient(addr)
|
|
|
|
if __name__ == '__main__':
|
|
test()
|