客户端向RabbitMQ发送消息的端口及配置可行性技术问询

背景代码 #

你提供的RabbitMQ发布者实现代码如下：

class RabbitMqPublisher
{
    private IAdvancedBus _advancedBus;
    public RabbitMqPublisher()
    {
        _advancedBus = RabbitHutch.CreateBus("host=rabbitmq-server:5672;virtualHost=/;username=user;password=pass").Advanced;
    }

    public void PublishMessage(string message)
    {
        var routingKey = "SimpleMessage";

        // declare some objects
        var queue = _advancedBus.QueueDeclare("TestQueue.SimpleMessage");
        var exchange = _advancedBus.ExchangeDeclare("TestExchange.SimpleMessage", ExchangeType.Direct);
        var binding = _advancedBus.Bind(exchange, queue, routingKey);

        _advancedBus.Publish(exchange, routingKey, true, new Message<string>(message));
    }
}

问题解答 #

客户端发送消息使用的端口 #

默认情况下，客户端发送消息时使用的是操作系统自动分配的临时端口（不同系统的临时端口范围略有差异，比如Windows通常为49152-65535，Linux通常为32768-65535）。这个端口是客户端本地随机选取的未被占用的端口，用于和RabbitMQ服务器的5672端口建立TCP连接。

是否可以配置客户端端口 #

可以配置。因为你使用的是EasyNetQ框架，通过构建ConnectionConfiguration对象并指定LocalPort属性，就能固定客户端使用的端口。修改后的代码示例如下：

class RabbitMqPublisher
{
    private IAdvancedBus _advancedBus;
    public RabbitMqPublisher()
    {
        var config = new ConnectionConfiguration
        {
            Hosts = new List<HostConfiguration> { new HostConfiguration { Host = "rabbitmq-server", Port = 5672 } },
            VirtualHost = "/",
            UserName = "user",
            Password = "pass",
            LocalPort = 12345 // 指定客户端使用的本地端口
        };
        _advancedBus = RabbitHutch.CreateBus(config).Advanced;
    }

    public void PublishMessage(string message)
    {
        var routingKey = "SimpleMessage";

        var queue = _advancedBus.QueueDeclare("TestQueue.SimpleMessage");
        var exchange = _advancedBus.ExchangeDeclare("TestExchange.SimpleMessage", ExchangeType.Direct);
        var binding = _advancedBus.Bind(exchange, queue, routingKey);

        _advancedBus.Publish(exchange, routingKey, true, new Message<string>(message));
    }
}

注意：指定的本地端口必须是客户端本地未被其他进程占用的端口，否则会抛出连接失败的异常。

内容的提问来源于stack exchange，提问作者meJustAndrew