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Python dictionary for intermediate queue processes

This is not very important, just a stupid experiment. I would like to create my own messaging. I would like to have a queue dictionary where each key is a process PID. Because I would like the processes (created by Process ()) to exchange messages, inserting them into the queue of the process that they want to send (knowing its pid). This is stupid code:

from multiprocessing import Process, Manager, Queue
from os import getpid
from time import sleep

def begin(dic, manager, parentQ):
    parentQ.put(getpid())
    dic[getpid()] = manager.Queue()
    dic[getpid()].put("Something...")

if __name__== '__main__':
    manager = Manager()
    dic = manager.dict()
    parentQ = Queue()

    p = Process(target = begin, args=(dic, manager, parentQ))
    p.start()
    son = parentQ.get()
    print son
    sleep(2)
    print dic[son].get()

dic[getpid()] = manager.Queue()It works great. But when I execute dic[son].put()/get()I get this message:

Process Process-2:
Traceback (most recent call last):
  File "/usr/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
    self.run()
  File "/usr/lib/python2.7/multiprocessing/process.py", line 114, in run
    self._target(*self._args, **self._kwargs)
  File "mps.py", line 8, in begin
    dic[getpid()].put("Something...")
  File "<string>", line 2, in __getitem__
  File "/usr/lib/python2.7/multiprocessing/managers.py", line 773, in _callmethod
    raise convert_to_error(kind, result)
RemoteError: 
---------------------------------------------------------------------------
Unserializable message: ('#RETURN', <Queue.Queue instance at 0x8a92d0c>)
---------------------------------------------------------------------------

Do you know how to do it right?

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1 answer

, , , . multiprocessing.Manager() , , , dict, - ( picklable Pythonese). , , :

from multiprocessing import Process, Manager, Queue
from os import getpid

number_of_subprocesses_i_want = 5

def begin(myQ):
    myQ.put("Something sentimental from your friend, PID {0}".format(getpid()))
    return

if __name__== '__main__':
    queue_dic = {}
    queue_manager = Manager()

    process_list = []

    for i in xrange(number_of_subprocesses_i_want):
        child_queue = queue_manager.Queue()

        p = Process(target = begin, args=(child_queue,))
        p.start()
        queue_dic[p.pid] = child_queue
        process_list.append(p)

    for p in process_list:
        print(queue_dic[p.pid].get())
        p.join()

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(destination_pid, sender_pid, message)

.. destination_pid (sender_pid, message) . , , , .

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