Question

我正在尝试使用rabbitmq-delayed-message-exchange插件，该插件似乎可以正常发送延迟消息，该消息将在延迟间隔后收到。在消费消息时，我应该在rabbitmq tutorial 2中实现通常的循环方法，但我收到的是多个消费者消费相同的消息。客户端功能是我在做basic.consume的地方。它与循环教程中的代码和延迟插件大致相同。

代码的工作方式如下所示 - 接收函数接收一条消息，该消息具有特定的延迟，将在队列中发回以供以后使用。发送消息以延迟发送消息。

我面临的问题是使用basic.consume，由于一些配置错误，我想我会让多个消费者使用相同的消息。

我是否需要更改以实现多个消费者避免处理相同请求。

class cities:
    def __init__(self):
        self.connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
        self.channel = self.connection.channel()
        self.channel.exchange_declare("test-x", type="x-delayed-message", arguments={"x-delayed-type":"direct"})
        self.channel.queue_declare(queue='towns_queue')
        self.channel.queue_bind(queue="towns_queue", exchange="test-x", routing_key="towns_queue")
        self.logger = logging.getLogger("rabbitmq")
        self.logger.setLevel(logging.DEBUG)
        handler = RotatingFileHandler("logs/Receive.log", maxBytes=100*1024*1024, backupCount=100)
        self.logger.addHandler(handler)
        formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
        handler.setFormatter(formatter)
        self.errlogger = logging.getLogger("Msg_timer_Error")
        self.errlogger.setLevel(logging.ERROR)
        errhandler = RotatingFileHandler("logs/towns_error.log", maxBytes=100*1024*1024, backupCount=100)
        self.errlogger.addHandler(errhandler)
        errformatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
        errhandler.setFormatter(errformatter)

    def call_api(self,url):
        do something

    def server_log(self,msg,value):
        self.logger.info(msg+" : "+str(value))

    def send_msg(self,msg,delay):
        try:
            delay = delay - 40
            self.server_log("Delay Set : ",delay)
            delay *=1000
            self.channel.basic_publish(exchange='test-x',routing_key='towns_queue',body=msg,properties=pika.BasicProperties(headers={"x-delay"\
:delay},delivery_mode=1))
            self.server_log("Msg Sent",msg)
        except:
            self.errlogger.exception(msg)
            self.errlogger.exception(str(traceback.print_exc()))
            pass

    def receive(self,ch, method, properties, body):
        try:
            self.server_log("Received message : ",body)
            self.process(body)
            time.sleep(1)
            ch.basic_ack(delivery_tag = method.delivery_tag)
            return body
        except:
            self.errlogger.exception(body)
            self.errlogger.exception(str(traceback.print_exc()))
            pass

    def process(self,body):
        delay=self.call_api(body)
        if delay:
           self.send_msg(body,delay)

   def client(self):
        try:
            self.channel.basic_qos(prefetch_count=1)
            self.channel.basic_consume(self.receive,queue='towns_queue',no_ack=False)
            self.channel.start_consuming()
        except:
            self.errlogger.exception(str(traceback.print_exc()))
         pass

    def close(self):
         try:
            self.connection.close()
         except:
            self.errlogger.exception(str(traceback.print_exc()))
           pass

def multiprocess(num_process=4):
    procs = []
    objs = []
    for i in range(4):
        p = multiprocessing.Process(target=cities().client)
    p.start()
        procs.append(p)
    for p in procs:
        p.join()

if __name__ == "__main__":
    if len(sys.argv)> 1:
        num_proc = sys.argv[1]
        if num_proc.isdigit():
            num_proc = int(num_proc)
            multiprocess(num_proc)
        else:
            raise Exception ('num_of_processes needs to be an integer.')
    else:
        multiprocess()

感谢任何帮助。

更新：

这可能有问题：

def client(self):
     try:
         self.channel.basic_qos(prefetch_count=1)
         self.channel.basic_consume(self.receive,queue='towns_queue',no_ack=False)
         self.channel.start_consuming()
     except:
         self.errlogger.exception(str(traceback.print_exc()))
         pass

Answer 1

本教程中的示例为每条消息创建一个新连接。我尝试通过改变我的send_message函数来这样工作，在那里我将创建一个新的客户端对象，它将创建一个新的连接来发送并在完成后关闭连接。所以，一旦改变了，它就会起作用。

ERROR: (gcloud.compute.forwarding-rules.describe) Could not fetch resource:
 - The resource 'projects/my-project/regions/us-central1/forwardingRules/my-forwarding' was not found

此外，必须更改__init__构造函数以避免每次都创建记录器，但这不是问题的一部分。

Rabbitmq多个消费者接收相同的消息，而不是循环

1 个答案: