物联网微消息队列MQTT介绍-EMQX集群搭建以及与SpringBoot整合

1.手机端向主题 topic111 发送信息并接收。(手机测试工具名称:MQTT调试器）

2.打印控制台

MQTT 用于物联网 (IoT) 的 OASIS 标准信息传输协议。它被设计成一个非常轻的发布/订阅信息传输，非常适合连接具有小代码足迹和最小网络带宽的远程设备。

MQTT 是客户端服务器发布/订阅消息传输协议。它重量轻，开放，简单，易于实施。这些特性使它们非常适合在许多情况下使用，包括有限的环境，如机器 (M2M) 和物联网 (IoT) 环境中的通信需要小代码足迹和/或网络带宽。

该协议通过 TCP/IP 或其他提供有序、无损、双向连接的网络协议。其特点包括：

·利用发布/订阅消息模式，提供一对多的消息分发和应用程序解耦。

·新闻传输与有效负载内容无关。

·三种服务质量：

标准物联网协议开放 MQTT、CoAP 和 LwM2M 连接任何设备 EMQX Enterprise 集群很容易扩展到数千万 MQTT 连接。

并且EMQX还是开源，支持集群，所以还是不错的选择

1.两个服务器:我的两个服务器，一个是腾讯云，一个是阿里云(别问为什么，薅羊毛)，我们暂时叫他们mqtt_service_aliyun和

mqtt_service_txyun 吧。
2.域名： mqtt.zhouhong.icu

## 1.下载 wget https://www.emqx.com/zh/downloads/broker/4.4.4/emqx-4.4.4-otp24.1.5-3-el8-amd64.rpm ## 2.安装 sudo yum install emqx-4.4.4-otp24.1.5-3-el8-amd64.rpm ## 3.修改配置文件 vim /etc/emqx/emqx.conf ## 4.修改以下内容 ## 注意node.name服务器的名称是目前的 node.name = mqtt\_service\_txyun@xxx.xx.xxx.xx cluster.static.seeds = mqtt\_service\_txyun@xxx.xx.xxx.xx,mqtt\_service\_aliyun@xxx.xx.xxx.xx cluster.discovery = static cluster.name = my-mqtt-cluster 

sudo emqx start 

nginx建造很简单。您只需修改以下内容nginx.conf内容可以

stream {  upstream mqtt.zhouhong.icu {  zone tcp\_servers 64k;  hash $remote\_addr;  server xxx.xx.xxx.xx:1883 weight=1 max\_fails=3 fail\_timeout=30s;  server xxx.xx.xxx.xx:1883 weight=1 max\_fails=3 fail\_timeout=30s;   }   server {  listen 8883 ssl;  status\_zone tcp\_server;  proxy\_pass mqtt.zhouhong.icu;  proxy\_buffer\_size 4k;  ssl\_handshake\_timeout 15s;  ssl\_certificate /etc/nginx/7967358\_www.mqtt.zhouhong.icu.pem;  ssl\_certificate\_key /etc/nginx/7967358\_www.mqtt.zhouhong.icu.key;  } } 

          org.springframework.integration  spring-integration-stream             org.springframework.integration  spring-integration-mqtt   

server:  port: 8080  mqtt: ## 单机版--只需要把域名改为ip既可   hostUrl: tcp://mqtt.zhouhong.icu:1883  username: admin  password: public  ## 服务端 clientId (自定义发送端)  clientId: service\_client\_id  cleanSession: true  reconnect: true  timeout: 100  keepAlive: 100  defaultTopic: topic111  qos: 0 

/**
 * description: 发生消息成功后 的 回调
 * date: 2022/6/16 15:55
 *
 * @author: zhouhong
 */
@Component
@Log4j2
public class MqttSendCallBack implements MqttCallbackExtended {

 /**
 * 客户端断开后触发
 * @param throwable
 */
 @Override
 public void connectionLost(Throwable throwable) {
 log.info("发送消息回调: 连接断开，可以做重连");
 }

 /**
 * 客户端收到消息触发
 *
 * @param topic 主题
 * @param mqttMessage 消息
 */
 @Override
 public void messageArrived(String topic, MqttMessage mqttMessage) throws Exception {
 log.info("发送消息回调: 接收消息主题 : " + topic);
 log.info("发送消息回调: 接收消息内容 : " + new String(mqttMessage.getPayload()));
 }

 /**
 * 发布消息成功
 *
 * @param token token
 */
 @Override
 public void deliveryComplete(IMqttDeliveryToken token) {
 String[] topics = token.getTopics();
 for (String topic : topics) {
 log.info("发送消息回调: 向主题：" + topic + "发送消息成功！");
 }
 try {
 MqttMessage message = token.getMessage();
 byte[] payload = message.getPayload();
 String s = new String(payload, "UTF-8");
 log.info("发送消息回调: 消息的内容是：" + s);
 } catch (MqttException e) {
 e.printStackTrace();
 } catch (UnsupportedEncodingException e) {
 e.printStackTrace();
 }
 }

 /**
 * 连接emq服务器后触发
 *
 * @param b
 * @param s
 */
 @Override
 public void connectComplete(boolean b, String s) {
 log.info("--------------------ClientId:"
                + MqttAcceptClient.client.getClientId() + "客户端连接成功！--------------------");
 }
}

/**
 * description: 接收消息后的回调
 * date: 2022/6/16 15:52
 *
 * @author: zhouhong
 */
@Component
@Log4j2
public class MqttAcceptCallback implements MqttCallbackExtended {

 @Resource
 private MqttAcceptClient mqttAcceptClient;

 /**
 * 客户端断开后触发
 *
 * @param throwable
 */
 @Override
 public void connectionLost(Throwable throwable) {
 log.info("接收消息回调: 连接断开，可以做重连");
 if (MqttAcceptClient.client == null || !MqttAcceptClient.client.isConnected()) {
 log.info("接收消息回调: emqx重新连接....................................................");
 mqttAcceptClient.reconnection();
 }
 }

 /**
 * 客户端收到消息触发
 *
 * @param topic 主题
 * @param mqttMessage 消息
 */
 @Override
 public void messageArrived(String topic, MqttMessage mqttMessage) throws Exception {
 log.info("接收消息回调: 接收消息主题 : " + topic);
 log.info("接收消息回调: 接收消息内容 : " + new String(mqttMessage.getPayload()));
 }

 /**
 * 发布消息成功
 *
 * @param token token
 */
 @Override
 public void deliveryComplete(IMqttDeliveryToken token) {
 String[] topics = token.getTopics();
 for (String topic : topics) {
 log.info("接收消息回调: 向主题：" + topic + "发送消息成功！");
 }
 try {
 MqttMessage message = token.getMessage();
 byte[] payload = message.getPayload();
 String s = new String(payload, "UTF-8");
 log.info("接收消息回调: 消息的内容是：" + s);
 } catch (MqttException e) {
 e.printStackTrace();
 } catch (UnsupportedEncodingException e) {
 e.printStackTrace();
 }
 }

 /**
 * 连接emq服务器后触发
 *
 * @param b
 * @param s
 */
 @Override
 public void connectComplete(boolean b, String s) {
 log.info("--------------------ClientId:"
                + MqttAcceptClient.client.getClientId() + "客户端连接成功！--------------------");
 // 以/#结尾表示订阅所有以test开头的主题
 // 订阅所有机构主题
        mqttAcceptClient.subscribe("topic111", 0);
 }
}

/**
 * description: 发送消息
 * date: 2022/6/16 16:01
 *
 * @author: zhouhong
 */
@Component
public class MqttSendClient {

 @Autowired
 private MqttSendCallBack mqttSendCallBack;

 @Autowired
 private MqttProperties mqttProperties;

 public MqttClient connect() {
 MqttClient client = null;
 try {
 String uuid = UUID.randomUUID().toString().replaceAll("-","");
 client = new MqttClient(mqttProperties.getHostUrl(),uuid , new MemoryPersistence());
 MqttConnectOptions options = new MqttConnectOptions();
 options.setUserName(mqttProperties.getUsername());
 options.setPassword(mqttProperties.getPassword().toCharArray());
 options.setConnectionTimeout(mqttProperties.getTimeout());
 options.setKeepAliveInterval(mqttProperties.getKeepAlive());
 options.setCleanSession(true);
 options.setAutomaticReconnect(false);
 try {
 // 设置回调
 client.setCallback(mqttSendCallBack);
 client.connect(options);
 } catch (Exception e) {
 e.printStackTrace();
 }
 } catch (Exception e) {
 e.printStackTrace();
 }
 return client;
 }

 /**
 * 发布消息
 * 主题格式： server:report:$orgCode(参数实际使用机构代码)
 *
 * @param retained 是否保留
 * @param pushMessage 消息体
 */
 public void publish(boolean retained, String topic, String pushMessage) {
 MqttMessage message = new MqttMessage();
 message.setQos(mqttProperties.getQos());
 message.setRetained(retained);
 message.setPayload(pushMessage.getBytes());
 MqttClient mqttClient = connect();
 try {
 mqttClient.publish(topic, message);
 } catch (MqttException e) {
 e.printStackTrace();
 } finally {
 disconnect(mqttClient);
 close(mqttClient);
 }
 }

 /**
 * 关闭连接
 *
 * @param mqttClient
 */
 public static void disconnect(MqttClient mqttClient) {
 try {
 if (mqttClient != null) {
 mqttClient.disconnect();
 }
 } catch (MqttException e) {
 e.printStackTrace();
 }
 }

 /**
 * 释放资源
 *
 * @param mqttClient
 */
 public static void close(MqttClient mqttClient) {
 try {
 if (mqttClient != null) {
 mqttClient.close();
 }
 } catch (MqttException e) {
 e.printStackTrace();
 }
 }
}

/**
 * description: 服务器段端连接订阅消息、监控topic
 * date: 2022/6/16 15:52
 *
 * @author: zhouhong
 */
@Component
@Log4j2
public class MqttAcceptClient {

 @Autowired
 @Lazy
 private MqttAcceptCallback mqttAcceptCallback;

 @Autowired
 private MqttProperties mqttProperties;

 public static MqttClient client;

 private static MqttClient getClient() {
 return client;
 }

 private static void setClient(MqttClient client) {
 MqttAcceptClient.client = client;
 }

 /**
 * 客户端连接
 */
 public void connect() {
 MqttClient client;
 try {
 // clientId 使用服务器 yml里面配置的 clientId
            client = new MqttClient(mqttProperties.getHostUrl(), mqttProperties.getClientId(), new MemoryPersistence());
 MqttConnectOptions options = new MqttConnectOptions();
 options.setUserName(mqttProperties.getUsername());
 options.setPassword(mqttProperties.getPassword().toCharArray());
 options.setConnectionTimeout(mqttProperties.getTimeout());
 options.setKeepAliveInterval(mqttProperties.getKeepAlive());
 options.setAutomaticReconnect(mqttProperties.getReconnect());
 options.setCleanSession(mqttProperties.getCleanSession());
 MqttAcceptClient.setClient(client);
 try {
 // 设置回调
 client.setCallback(mqttAcceptCallback);
 client.connect(options);
 } catch (Exception e) {
 e.printStackTrace();
 }
 } catch (Exception e) {
 e.printStackTrace();
 }
 }

 /**
 * 重新连接
 */
 public void reconnection() {
 try {
 client.connect();
 } catch (MqttException e) {
 e.printStackTrace();
 }
 }

 /**
 * 订阅某个主题
 *
 * @param topic 主题
 * @param qos 连接方式
 */
 public void subscribe(String topic, int qos) {
 log.info("==============开始订阅主题==============" + topic);
 try {
 client.subscribe(topic, qos);
 } catch (MqttException e) {
 e.printStackTrace();
 }
 }

 /**
 * 取消订阅某个主题
 *
 * @param topic
 */
 public void unsubscribe(String topic) {
 log.info("==============开始取消订阅主题==============" + topic);
 try {
 client.unsubscribe(topic);
 } catch (MqttException e) {
 e.printStackTrace();
 }
 }
}

/**
 * description: 启动后连接 MQTT 服务器, 监听 mqtt/my\_topic 这个topic发送的消息
 * date: 2022/6/16 15:57
 * @author: zhouhong
 */
@Configuration
public class MqttConfig {

 @Resource
 private MqttAcceptClient mqttAcceptClient;

 @Bean
 public MqttAcceptClient getMqttPushClient() {
 mqttAcceptClient.connect();
 return mqttAcceptClient;
 }
}

/**
 * description: 发消息控制类
 * date: 2022/6/16 15:58
 *
 * @author: zhouhong
 */
@RestController
public class SendController {

 @Resource
 private MqttSendClient mqttSendClient;

 @PostMapping("/mqtt/sendmessage")
 public void sendMessage(@RequestBody SendParam sendParam) {
 mqttSendClient.publish(false,sendParam.getTopic(),sendParam.getMessageContent());
 }
}

• postman调用发消息接口

• 控制台日志

• 使用另外一个移动端MQTT调试工具测试

1. 手机端向主题 topic111 发送消息，并接收。

2. 控制台打印