What is the best way to end this thread when a function is called?

Question

I'm having a bit of trouble with this queue:

import Queue
import threading

class test(threading.Thread):

    def __init__(self):
        threading.Thread.__init__(self)
        self.request_queue = Queue.Queue()

    def addtoqueue(self, item):
        self.request_queue.put(item)

    def run(self):
        while True:
            item = self.request_queue.get(True)
            print item

This simple class implements a threaded queue. Calling test::addtoqueue will append an item to the queue. The thread waits for an item to be added to the queue - and immediately prints it and waits for the next thing.

My problem is application shutdown. What is the best way to terminate the thread? I could use a Condition, but how could I wait for either a notification from the Condition or a new item in the queue?

Answer 1

You can send some poison to the thread to kill it:

poison = None # something you wouldn't normally put in the Queue

class test(threading.Thread):

    def __init__(self):
        threading.Thread.__init__(self)
        self.request_queue = Queue.Queue()

    def kill(self):
        self.addtoqueue(poison)

    def addtoqueue(self, item):
        self.request_queue.put(item)

    def run(self):
        while True:
            item = self.request_queue.get(True)
            if item is poison:
                # do stuff
                return # end thread
            print item