import io
import multiprocessing.queues
from multiprocessing.reduction import ForkingPickler
import pickle
class ConnectionWrapper(object):
"""Proxy class for _multiprocessing.Connection which uses ForkingPickler to
serialize objects"""
def __init__(self, conn):
self.conn = conn
def send(self, obj):
buf = io.BytesIO()
ForkingPickler(buf, pickle.HIGHEST_PROTOCOL).dump(obj)
self.send_bytes(buf.getvalue())
def recv(self):
buf = self.recv_bytes()
return pickle.loads(buf)
def __getattr__(self, name):
if 'conn' in self.__dict__:
return getattr(self.conn, name)
raise AttributeError("'{}' object has no attribute '{}'".format(
type(self).__name__, 'conn'))
class Queue(multiprocessing.queues.Queue):
def __init__(self, *args, **kwargs):
super(Queue, self).__init__(*args, **kwargs)
self._reader: ConnectionWrapper = ConnectionWrapper(self._reader)
self._writer: ConnectionWrapper = ConnectionWrapper(self._writer)
self._send = self._writer.send
self._recv = self._reader.recv
class SimpleQueue(multiprocessing.queues.SimpleQueue):
def _make_methods(self):
if not isinstance(self._reader, ConnectionWrapper):
self._reader: ConnectionWrapper = ConnectionWrapper(self._reader)
self._writer: ConnectionWrapper = ConnectionWrapper(self._writer)
super(SimpleQueue, self)._make_methods() # type: ignore[misc]