RabbitMQ（四）远程连接RabbitMQ

今天药忘吃喽~ 2022-07-19 02:24 221阅读 0赞

为了避免污染宿主系统环境，于是在虚拟机中搭建了一个linux环境并且安装了rabbitmq-server。然后在远程连接的时候一直连接失败。官网上面给的例子都是在本地使用系统默认的guest用户连接的。没有给出远程连接的例子，于是阅读文档发现：

When the serverfirst starts running, and detects that its database is uninitialised or hasbeen deleted, it initialises a fresh database with the following resources:
     
        a virtual hostnamed /
        a user namedguest with a default password of guest, granted full access to the / virtualhost.

也就是刚刚安装好rabbitmq-server，系统会自动创建一个名为“/”的virtual host，同时也会创建一个用户名和密码都是guest的用户，并且应用"/ virtual host"的所有访问权限。因此在rabbitmq安装的机器上使用官网给出的例子：

public class Send {
            // 队列名称
            privatefinal static String QUEUE_NAME = "hello";
     
            publicstatic void main(String[] argv) throws java.io.IOException {
                   /**
                    * 创建连接连接到MabbitMQ
                    */
                   ConnectionFactoryfactory = new ConnectionFactory();
                   // 设置MabbitMQ所在主机ip或者主机名
                   factory.setHost("localhost");
                  
                   // 创建一个连接
                   Connectionconnection = factory.newConnection();
                   // 创建一个频道
                   Channelchannel = connection.createChannel();
                  
                   // 指定一个队列
                   channel.queueDeclare(QUEUE_NAME,false, false, false, null);
                  
                   // 发送的消息
                   Stringmessage = "hello world!";
                   // 往队列中发出一条消息
                   channel.basicPublish("",QUEUE_NAME, null, message.getBytes());
                   System.out.println("[x] Sent '" + message + "'");
                  
                   // 关闭频道和连接
                   channel.close();
                   connection.close();
            }
    }

运行是没问题的。如果要切换到远程机器访问的话，单纯的修改factory.setHost("localhost")是不行的。因为guest用户只是被容许从localhost访问。官网文档描述如下：

"guest" user can only connect via localhost
     
        By default, theguest user is prohibited from connecting to the broker remotely; it can onlyconnect over a > loopback interface (i.e. localhost). This applies both toAMQP and to any other protocols enabled via plugins. Any > other users youcreate will not (by default) be restricted in this way.
     
        This isconfigured via the loopback_users item in the configuration file.
     
        If you wish toallow the guest user to connect from a remote host, you should set theloopback_users configuration item to []. A complete rabbitmq.config which doesthis would look like:

默认情况下，使用下面的命令：

rabbitmqctl environment

会发现：

![Center][]

我现在不想使用默认的guest用户，我新建立了一个用户test，然后授予所有权限，使用下面的命令：

rabbitmqctl add_user test 123456
    rabbitmqctl set_user_tags test administrator
    rabbitmqctl set_permissions -p / test ".*"".*" ".*"

创建用户

![Center 1][]

为用户设置角色

![Center 2][]

为用户设置权限

![Center 3][]

这种方式设置的默认的“/”权限，还可以自己添加其它权限

rabbitmqctl add_vhost vhost_test

![Center 4][]

![Center 5][]

然后使用下面的代码远程访问

public class Send2 {
    	// 队列名称
    	private final static String QUEUE_NAME = "hello";
    
    	public static void main(String[] argv) throws java.io.IOException {
    		/**
    		 * 创建连接连接到MabbitMQ
    		 */
    		ConnectionFactory factory = new ConnectionFactory();
    		// 设置MabbitMQ所在主机ip或者主机名
    		factory.setHost("localhost");
    		factory.setPort(5672);
    		factory.setUsername("test");
    		factory.setPassword("123456");
    		factory.setVirtualHost("vhost_test");
    		
    		// 创建一个连接
    		Connection connection = factory.newConnection();
    		// 创建一个频道
    		Channel channel = connection.createChannel();
    		
    		// 指定一个队列
    		channel.queueDeclare(QUEUE_NAME, false, false, false, null);
    		
    		// 发送的消息
    		String message = "hello world!";
    		// 往队列中发出一条消息
    		channel.basicPublish("", QUEUE_NAME, null, message.getBytes());
    		System.out.println(" [x] Sent '" + message + "'");
    		
    		// 关闭频道和连接
    		channel.close();
    		connection.close();
    	}
    }

public class Recv2 {
    	// 队列名称
    	private final static String QUEUE_NAME = "hello";
    
    	public static void main(String[] argv) throws java.io.IOException,
    			ShutdownSignalException, ConsumerCancelledException,
    			InterruptedException {
    		
    		// 打开连接和创建频道，与发送端一样
    		ConnectionFactory factory = new ConnectionFactory();
    		factory.setHost("localhost");
    		factory.setPort(5672);
    		factory.setUsername("test");
    		factory.setPassword("123456");
    		factory.setVirtualHost("vhost_test");
    		
    		Connection connection = factory.newConnection();
    		Channel channel = connection.createChannel();
    		
    		// 声明队列，主要为了防止消息接收者先运行此程序，队列还不存在时创建队列。
    		channel.queueDeclare(QUEUE_NAME, false, false, false, null);
    		System.out.println(" [*] Waiting for messages. To exit press CTRL+C");
    
    		// 创建队列消费者
    		QueueingConsumer consumer = new QueueingConsumer(channel);
    		// 指定消费队列
    		channel.basicConsume(QUEUE_NAME, true, consumer);
    		
    		while (true) {
    			// nextDelivery是一个阻塞方法（内部实现其实是阻塞队列的take方法）
    			QueueingConsumer.Delivery delivery = consumer.nextDelivery();
    			String message = new String(delivery.getBody());
    			System.out.println(" [x] Received '" + message + "'");
    		}
    	}
    }

输出：

[*] Waiting for messages. To exit press CTRL+C
     [x] Received 'hello world!'

这次连接成功，测试通过

[Center]: /images/20220718/2d9b94dcfe0a499d8a9abd28d5a15075.png
[Center 1]: /images/20220718/183b49d73461425ba6de4b0928c57916.png
[Center 2]: /images/20220718/18a21f44418b4426a71fff36670ff6d4.png
[Center 3]: /images/20220718/fed3cb7ea71948bdbdedb18c4a697845.png
[Center 4]: /images/20220718/242597738d944bab8923ced330db1348.png
[Center 5]: /images/20220718/d5516f7ba8be47b7a8c94faea25161c5.png