Python线程：如何使用外部脚本的返回值？

Question

(I found a decent solution here for this, but unfortunately I'm using IronPython which does not implement the mutliprocessing module ...)

Driving script Threader.py will call Worker.py's single function twice, using the threading module. Its single function just fetches a dictionary of data.

Roughly speaking:

Worker.py

def GetDict():
    :
    :
    :
    return theDict

Threader.py

import threading
from Worker import GetDict
    :
    :
    :
def ThreadStart():
    t = threading.Thread(target=GetDict)
    t.start()
    :
    :

In the driver script Threader.py, I want to be able to operate on the two dictionaries outputted by the 2 instances of Worker.py.

The accepted answer here involving the Queue module seems to be what I need in terms of accessing return values, but this is written from the point of view of everthing being doen in a single script. How do I go about making the return values of the function called in Worker.py available to Threader.py (or any other script for that matter)?

Many thanks

Answer 1

another way to do what you want (without using a Queue ) would be by using the concurrent.futures module (from python3.2, for earlier versions there is a backport ).

using this, your example would work like this:

from concurrent import futures

def GetDict():
    return {'foo':'bar'}

# imports ...
# from Worker import GetDict

def ThreadStart():
    executor = futures.ThreadPoolExecutor(max_workers=4)
    future = executor.submit(GetDict)
    print(future.result()) # blocks until GetDict finished

    # or doing more then one:
    jobs = [executor.submit(GetDict) for i in range(10)]
    for j in jobs:
        print(j.result())

if __name__ == '__main__':
    ThreadStart()

edit:

something similar woule be to use your own thread to execute the target function and save it's return value, something like this:

from threading import Thread

def GetDict():
    return {'foo':'bar'}

# imports ...
# from Worker import GetDict

class WorkerThread(Thread):

    def __init__(self, fnc, *args, **kwargs):
        super(WorkerThread, self).__init__()
        self.fnc = fnc
        self.args = args
        self.kwargs = kwargs

    def run(self):
        self.result = self.fnc(*self.args, **self.kwargs)


def ThreadStart():
    jobs = [WorkerThread(GetDict) for i in range(10)]
    for j in jobs:
        j.start()
    for j in jobs:
        j.join()
        print(j.result)

if __name__ == '__main__':
    ThreadStart()