rabbitmq 生产者 消费者(多个线程消费同一个队列里面的任务。) 一个通用rabbitmq消费确认,快速并发运行的框架。

rabbitmq作为消息队列可以有消息消费确认机制,之前写个基于redis的通用生产者 消费者 并发框架,redis的list结构可以简单充当消息队列,但不具备消费确认机制,随意关停程序,会丢失一部分正在程序中处理但还没执行完的消息。基于redis的与基于rabbitmq相比对消息消费速度和消息数量没有天然的支持。

使用rabbitmq的最常用库pika

 

 不管是写代码还是运行起来都比celery使用更简单,基本能够满足绝大多数场景使用,用来取代celery  worker模式(celery有三个模式,worker模式最常用,其余是定时和间隔时间两种模式)的后台异步的作用。

 

 

# coding=utf-8
"""
一个通用的rabbitmq生产者和消费者。使用多个线程消费同一个消息队列。
"""
from collections import Callable
import functools
import time
from threading import Lock
from pika import BasicProperties
# noinspection PyUnresolvedReferences
from app.utils_ydf import (LoggerMixin, LogManager, decorators, RabbitMqHelper, BoundedThreadPoolExecutor)


class RabbitmqPublisher(LoggerMixin):
    def __init__(self, queue_name, log_level_int=1):
        self._queue_name = queue_name
        self.logger.setLevel(log_level_int * 10)
        channel = RabbitMqHelper().creat_a_channel()
        channel.queue_declare(queue=queue_name, durable=True)
        self.channel = channel
        self.lock = Lock()
        self._current_time = None
        self.count_per_minute = None
        self._init_count()
        self.logger.info(f'{self.__class__} 被实例化了')

    def _init_count(self):
        self._current_time = time.time()
        self.count_per_minute = 0

    def publish(self, msg):
        with self.lock:  # 亲测pika多线程publish会出错。
            self.channel.basic_publish(exchange='',
                                       routing_key=self._queue_name,
                                       body=msg,
                                       properties=BasicProperties(
                                           delivery_mode=2,  # make message persistent
                                       )
                                       )
            self.logger.debug(f'放入 {msg} 到 {self._queue_name} 队列中')
            self.count_per_minute += 1
            if time.time() - self._current_time > 60:
                self._init_count()
                self.logger.info(f'一分钟内推送了 {self.count_per_minute} 条消息到 {self.channel.connection} 中')


class RabbitmqConsumer(LoggerMixin):
    def __init__(self, queue_name, consuming_function: Callable = None, threads_num=100, max_retry_times=3, log_level=1, is_print_detail_exception=True):
        """
        :param queue_name:
        :param consuming_function: 处理消息的函数,函数有且只能有一个参数,参数表示消息。是为了简单,放弃策略和模板来强制参数。
        :param threads_num:
        :param max_retry_times:
        :param log_level:
        :param is_print_detail_exception:
        """
        self._queue_name = queue_name
        self.consuming_function = consuming_function
        self.threadpool = BoundedThreadPoolExecutor(threads_num)
        self._max_retry_times = max_retry_times
        self.logger.setLevel(log_level * 10)
        self.logger.info(f'{self.__class__} 被实例化')
        self._is_print_detail_exception = is_print_detail_exception
        self.rabbitmq_helper = RabbitMqHelper(heartbeat_interval=30)
        channel = self.rabbitmq_helper.creat_a_channel()
        channel.queue_declare(queue=self._queue_name, durable=True)
        channel.basic_qos(prefetch_count=threads_num)
        self.channel = channel
        LogManager('pika.heartbeat').get_logger_and_add_handlers(1)

    @decorators.keep_circulating(1)  # 是为了保证无论rabbitmq异常中断多久,无需重启程序就能保证恢复后,程序正常。
    def start_consuming_message(self):
        def callback(ch, method, properties, body):
            msg = body.decode()
            self.logger.debug(f'从rabbitmq取出的消息是:  {msg}')
            # ch.basic_ack(delivery_tag=method.delivery_tag)
            self.threadpool.submit(self.__consuming_function, ch, method, properties, msg)

        self.channel.basic_consume(callback,
                                   queue=self._queue_name,
                                   # no_ack=True
                                   )
        self.channel.start_consuming()

    @staticmethod
    def ack_message(channelx, delivery_tagx):
        """Note that `channel` must be the same pika channel instance via which
        the message being ACKed was retrieved (AMQP protocol constraint).
        """
        if channelx.is_open:
            channelx.basic_ack(delivery_tagx)
        else:
            # Channel is already closed, so we can't ACK this message;
            # log and/or do something that makes sense for your app in this case.
            pass

    def __consuming_function(self, ch, method, properties, msg, current_retry_times=0):
        if current_retry_times < self._max_retry_times:
            # noinspection PyBroadException
            try:
                self.consuming_function(msg)
                # ch.basic_ack(delivery_tag=method.delivery_tag)
                self.rabbitmq_helper.connection.add_callback_threadsafe(functools.partial(self.ack_message, ch, method.delivery_tag))
            except Exception as e:
                self.logger.error(f'函数 {self.consuming_function}  第{current_retry_times+1}次发生错误,\n 原因是{e}', exc_info=self._is_print_detail_exception)
                self.__consuming_function(ch, method, properties, msg, current_retry_times + 1)
        else:
            self.logger.critical(f'达到最大重试次数 {self._max_retry_times} 后,仍然失败')
            # ch.basic_ack(delivery_tag=method.delivery_tag)
            self.rabbitmq_helper.connection.add_callback_threadsafe(functools.partial(self.ack_message, ch, method.delivery_tag))


if __name__ == '__main__':
    rabbitmq_publisher = RabbitmqPublisher('queue_test')
    [rabbitmq_publisher.publish(str(i)) for i in range(1000)]


    def f(msg):
        print('....  ', msg)
        time.sleep(10)  # 模拟做某事需要10秒种。


    rabbitmq_consumer = RabbitmqConsumer('queue_test', consuming_function=f, threads_num=20)
    rabbitmq_consumer.start_consuming_message()

 

 

1、放入任务 (图片鼠标右键点击新标签打开查看原图)

  /2、

2、开启消费者,写一个函数传给消费者类。

 

 3、并发运行效果。

 

 

rabbitmq这个专业的消息中间件就是比redis作为消息中间件专业了很多。

 

posted @ 2018-12-19 14:14  北风之神0509  阅读(10756)  评论(4编辑  收藏  举报