python 生产者消费者demo

# -*- coding:utf-8 -*-
from multiprocessing import JoinableQueue, Process, Value

import time

DOWNLOAD_EXCEPTION_MINUTE = 3
DEAL_EXCEPTION_MINUTE = 2


class SharedObj(object):
    def __init__(self, id):
        self.id = id
        pass


from collections import namedtuple

SHARED_OBJ = namedtuple("shared_obj", ["id"])


def download_process(produce_queue, minute_list, sharded_time_cost, shared_is_exception):
    def process(minute_name):
        print("Begin download process minute:%s." % minute_name)
        # if minute_name == DOWNLOAD_EXCEPTION_MINUTE:
        #     raise Exception("Exception in minute_name:%s when download process." % minute_name)

        time.sleep(10)
        print("Success download progress minute:%s." % minute_name)

    try:
        start_time = time.time()
        for minute_name in minute_list:
            if shared_is_exception.value:
                print("Some other error happened when begin download minute:%s." % minute_name)
                break
            process(minute_name)
            produce_queue.put(minute_name)
        end_time = time.time()
        with sharded_time_cost.get_lock():
            sharded_time_cost.value = int(end_time - start_time)
    except Exception as e:
        print(e)
        if shared_is_exception.value:
            print("Some other error happened.")

        with shared_is_exception.get_lock():
            shared_is_exception.value = 1
    #
    produce_queue.put(None)
    produce_queue.join()


def deal_process(produce_queue, shared_deal_time_cost, shared_done_minute_name, shared_done_count, shared_is_exception,
                 s):
    def process():
        print("Begin deal minute:%s." % minute_name)
        # if minute_name == DEAL_EXCEPTION_MINUTE:
        #     raise Exception("Exception happened in minute:%s, when deal." % minute_name)
        print(s)
        time.sleep(5)
        print("Done for deal minute:%s." % minute_name)

    while True:
        minute_name = produce_queue.get()
        #
        print("-----deal process----")
        print("shared_deal_time_cost:%s." % shared_deal_time_cost.value)
        print("shared_done_minute_name:%s." % shared_done_minute_name.value)
        print("shared_done_count:%s." % shared_done_count.value)
        print("shared_is_exception:%s." % shared_is_exception.value)
        print("---------------------")
        #
        if minute_name is None:
            print("Get empty minute name, done for deal.")
            produce_queue.task_done()
            break

        try:
            begin_time = time.time()
            if not shared_is_exception.value:
                process()
            else:
                print("shared_is_exception is true, exception is happened; continue...")
            end_time = time.time()
            #
            with shared_deal_time_cost.get_lock():
                shared_deal_time_cost.value += int(end_time - begin_time)
            with shared_done_minute_name.get_lock():
                shared_done_minute_name.value = minute_name
            with shared_done_count.get_lock():
                shared_done_count.value += 1
        except Exception as e:
            print (e)
            if not shared_is_exception.value:
                with shared_is_exception.get_lock():
                    shared_is_exception.value = 1
        finally:
            #
            produce_queue.task_done()


class TestObj(object):
    def __init__(self):
        self.shared_done_minute = Value("i", 0)
        self.shared_done_count = Value("i", 0)
        self.shared_download_time_cost = Value("i", 0)
        self.shared_deal_time_cost = Value("i", 0)
        self.shared_is_exception = Value("i", 0)

    def main_process(self, ):
        minute_list = [1, 2, 3, 4, 5]
        #
        produce_queue = JoinableQueue()
        download_processor = Process(target=download_process,
                                     args=(produce_queue, minute_list, self.shared_download_time_cost,
                                           self.shared_is_exception,))
        #
        s = SharedObj(id=1)
        print(s)
        deal_processor = Process(target=deal_process, args=(
            produce_queue, self.shared_deal_time_cost, self.shared_done_minute, self.shared_done_count,
            self.shared_is_exception, s,))
        start_time = time.time()
        #
        download_processor.daemon = True
        deal_processor.daemon = True
        #
        download_processor.start()
        deal_processor.start()
        #
        download_processor.join()
        deal_processor.join()
        #
        end_time = time.time()
        print("Main time cost:%s." % (end_time - start_time))


def main():
    test_obj = TestObj()
    test_obj.main_process()


if __name__ == '__main__':
    main()

  

原文地址:https://www.cnblogs.com/dasheng-maritime/p/13964195.html