连接到 RabbitMQ，方法级最佳实践？

Question

我有一个使用rabbitmq 读取和写入消息的类。我不想在此类的构造函数或读写方法中包含与连接相关的信息。相反，我想在使用写入和读取方法时建立连接。解决这个问题的最佳方法/做法是什么？

//编辑1

public class Rabbit : IMessageBus
{   
    // Implementation of methods for Rabbit class go here
    private List<string> publishQ = new List<string>();
    private List<string> subscribeQ = new List<string>();

    ConnectionFactory factory = null;
    IConnection connection = null;
    IModel channel = null;  
    QueueingBasicConsumer consumer = null;  


    public void write ( Measurement m1 )
    {
        byte[] body = Measurement.AltSerialize( m1 );

        foreach (string queue in publishQ) 
        {
            channel.BasicPublish("", queue, null, body);
            Console.WriteLine("\n  [x] Sent to queue {0}.", queue);
        }
    }

    public void publish(string queueName)
    {   
        channel.QueueDeclare(queueName, true, false, false, null); //durable=true

        publishQ.Add(queueName); //and, add it the list of queue names to publish to
    }

    public Measurement read() 
    {       
        foreach (string queue in subscribeQ) 
        {
            channel.BasicConsume(queue, true, consumer);
        }

        System.Console.WriteLine(" [*] Waiting for messages." +
                                "To exit press CTRL+C");
        BasicDeliverEventArgs ea = 
            (BasicDeliverEventArgs)consumer.Queue.Dequeue();

        return Measurement.AltDeSerialize(ea.Body);
    }

    public void subscribe(string queueName)
    {
        channel.QueueDeclare(queueName, true, false, false, null);
        subscribeQ.Add(queueName);
    }

    public static string MsgSysName;
    public string MsgSys
    {
        get 
        { 
            return MsgSysName;
        }
        set
        {
            MsgSysName = value;
        }
    }

    public Rabbit(string _msgSys) //Constructor
    {   
        factory = new ConnectionFactory();
        factory.HostName = "localhost"; 
        connection = factory.CreateConnection();
        channel = connection.CreateModel();
        consumer = new QueueingBasicConsumer(channel);

        System.Console.WriteLine("\nMsgSys: RabbitMQ");
        MsgSys = _msgSys;
    }

    ~Rabbit()
    {
        //
    }   
}

Answer 1

您是否考虑过将 Func 传递到构造函数中？换句话说，有一种方法可以让您在需要时获得连接？

（显然你需要在某个地方传递连接信息，除非你要静态访问它......不寒而栗。）

编辑：好的，我不熟悉 RabbitMQ，但假设它有某种实现 IDisposable 的 Connection 类，它看起来像这样：

public class MessageHandler
{
    private readonly Func<Connection> connectionProvider;

    public MessageHander(Func<Connection> connectionProvider)
    {
        this.connectionProvider = connectionProvider;
    }

    public void WriteMessage(string message)
    {
        using (Connection connection = connectionProvider.Invoke())
        {
            connection.DoSomething(message);
        }
    }
}

然后用类似的东西创建它：

MessageHandler handler = new MessageHandler(() => new Connection(server));

现在，如果涉及到任何更“有趣”的内容，您可能想要到编写一个单独的 ConnectionProvider 类。当然，RabbitMQ 可能有一些示例代码 - 您应该首先查阅它们及其文档，因为我真的不知道我在说什么:)