问题描述

RabbitMQ 3.5 现在支持消息优先级；但是，我无法构建一个工作示例.我把我的代码放在下面.它包括我期望的输出和我实际的输出.我会对更多文档和/或工作示例感兴趣.

RabbitMQ 3.5 now supports message priority; However, I am unable to build a working example. I've placed my code below. It includes the output that I expect and the output I actually. I'd be interested in more documentation, and/or a working example.

简而言之，我的问题是:如何在 Rabbit 3.5.0.0 中获得消息优先级?

So my question in short: How do I get message priority to work in Rabbit 3.5.0.0?

出版商:

using System;
using RabbitMQ.Client;
using System.Text;
using System.Collections.Generic;

class Publisher
{

    public static void Main()
    {
        var factory = new ConnectionFactory() { HostName = "localhost" };
        using (var connection = factory.CreateConnection())
        {
            using (var channel = connection.CreateModel())
            {
                IDictionary <String , Object> args = new Dictionary<String,Object>() ;
                args.Add(" x-max-priority ", 10);
                channel.QueueDeclare("task_queue1", true, false, true, args);

                for (int i = 1 ; i<=10; i++ )
                {
                    var message = "Message";
                    var body = Encoding.UTF8.GetBytes(message + " " + i);
                    var properties = channel.CreateBasicProperties();
                    properties.SetPersistent(true);
                    properties.Priority = Convert.ToByte(i);
                    channel.BasicPublish("", "task_queue1", properties, body);
                }
            }
        }
    }
}

消费者:

using System;
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using System.Text;
using System.Threading;
using System.Collections.Generic;

namespace Consumer
{ 
    class Worker
    {
        public static void Main()
        {
            var factory = new ConnectionFactory() { HostName = "localhost" };
            using (var connection = factory.CreateConnection())
            {
                using (var channel = connection.CreateModel())
                {
                    IDictionary<String, Object> args = new Dictionary<String, Object>();                      
                    channel.BasicQos(0, 1, false);
                    var consumer = new QueueingBasicConsumer(channel);
                    IDictionary<string, object> consumerArgs = new Dictionary<string, object>();
                    channel.BasicConsume( "task_queue1", false, "", args, consumer);
                    Console.WriteLine(" [*] Waiting for messages. " +
                                      "To exit press CTRL+C");
                    while (true)
                    {
                        var ea = (BasicDeliverEventArgs)consumer.Queue.Dequeue();
                        var body = ea.Body;
                        var message = Encoding.UTF8.GetString(body);
                        Console.WriteLine(" [x] Received {0}", message);
                        channel.BasicAck(ea.DeliveryTag, false);
                    }
                }
            }
        }
    }
}

实际输出:

[*] Waiting for messages. To exit press CTRL+C
[x] Received Message 1
[x] Received Message 2
[x] Received Message 3
[x] Received Message 4
[x] Received Message 5
[x] Received Message 6
[x] Received Message 7
[x] Received Message 8
[x] Received Message 9
[x] Received Message 10

预期输出:

[*] Waiting for messages. To exit press CTRL+C
[x] Received Message 10
[x] Received Message 9
[x] Received Message 8
[x] Received Message 7
[x] Received Message 6
[x] Received Message 5
[x] Received Message 4
[x] Received Message 3
[x] Received Message 2
[x] Received Message 1

更新 #1.我在 Java 中找到了一个示例 这里.然而，它是 Rabbit 3.4.x.x.已合并到 3.5 中的插件.我能看到的唯一区别是它们将优先级表示为一个 int 而我的是一个字节.但我觉得这是一个红鲱鱼.我在这里有点不知所措.

UPDATE #1. I found an example in Java here. However it's the Rabbit 3.4.x.x. addin that was incorporated into 3.5. The only difference I can see is that they express the priority as an int and mine is a byte. But I feel like that's a red herring. I'm at a bit of a loss here.

推荐答案

好吧，我解决了.这是一个愚蠢的错误.我写道:

Well I solved it. It was a dumb mistake. I wrote:

args.Add(" x-max-priority ", 10);

应该是的

args.Add("x-max-priority", 10);

我会留下这个，以便其他人可以在 C# 中获得 Rabbitmq 3.5 的优先级队列的工作示例.

I'll leave this up so other people can have a working example of Rabbitmq 3.5's Priority Queues in C#.

这篇关于RabbitMQ 3.5 和消息优先级的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！