一：前言
1、使用场景：最近对接物联网开发需要集成MQTT进行消息订阅
2、前置准备：首先需要下载部署好MQTT服务（推荐emqx），在我上一条博客里面有详细步骤，官方文档部署的也非常详细（因为网站在国外所以访问比较慢，可以参考文档）
链接： Download EMQX
二：代码
我们将代码全部集成到common模块下面
1、第一步导入依赖，在ruoyi-common模块下的pom文件导入依赖
<!--mqtt依赖-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-integration</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.integration</groupId>
<artifactId>spring-integration-stream</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.integration</groupId>
<artifactId>spring-integration-mqtt</artifactId>
</dependency>2、第二步在ruoyi-admin模块中找到application.yml文件中添加配置
# mqtt
mqtt:
username: admin # 用户名
password: public # 密码
hostUrl: tcp://IP:1883 # tcp://ip:端口
# clientId: mqttx_fdb83555 # 客户端id，线下
clientId: mqttx_fdb83518 # 客户端id，线上
defaultTopic: lob,test # 订阅主题
timeout: 100 # 超时时间 （单位：秒）
keepalive: 60 # 心跳 （单位：秒）
enabled: true # 是否使用mqtt功能3、第三步需要在ruoyi-common模块下src\main\java\com\superVisualization\common\utils目录下新建MqttConfig.java文件和mqtt文件夹添加MqttPushClient.java、PushCallback.java文件
MqttConfig.java
package com.ruoyi.common.utils;
import com.ruoyi.common.utils.mqtt.MqttPushClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;
@Component
@ConfigurationProperties("spring.mqtt")
public class MqttConfig {
@Autowired
private MqttPushClient mqttPushClient;
/**
* 用户名
*/
private String username;
/**
* 密码
*/
private String password;
/**
* 连接地址
*/
private String hostUrl;
/**
* 客户Id
*/
private String clientId;
/**
* 默认连接话题
*/
private String defaultTopic;
/**
* 超时时间
*/
private int timeout;
/**
* 保持连接数
*/
private int keepalive;
/**
* mqtt功能使能
*/
private boolean enabled;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getHostUrl() {
return hostUrl;
}
public void setHostUrl(String hostUrl) {
this.hostUrl = hostUrl;
}
public String getClientId() {
return clientId;
}
public void setClientId(String clientId) {
this.clientId = clientId;
}
public String getDefaultTopic() {
return defaultTopic;
}
public void setDefaultTopic(String defaultTopic) {
this.defaultTopic = defaultTopic;
}
public int getTimeout() {
return timeout;
}
public void setTimeout(int timeout) {
this.timeout = timeout;
}
public int getKeepalive() {
return keepalive;
}
public void setKeepalive(int keepalive) {
this.keepalive = keepalive;
}
public boolean isEnabled() {
return enabled;
}
public void setEnabled(boolean enabled) {
this.enabled = enabled;
}
@Bean
public MqttPushClient getMqttPushClient() {
if(enabled == true){
String mqtt_topic[] = StringUtils.split(defaultTopic, ",");
//连接
mqttPushClient.connect(hostUrl, clientId, username, password, timeout, keepalive);
for(int i=0; i<mqtt_topic.length; i++){
//订阅主题
mqttPushClient.subscribe(mqtt_topic[i], 1);
}
}
return mqttPushClient;
}
}MqttPushClient.java、PushCallback.java
package com.ruoyi.common.utils.mqtt;
import com.ruoyi.common.core.domain.AjaxResult;
import org.eclipse.paho.client.mqttv3.*;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
@Component
public class MqttPushClient {
private static final Logger logger = LoggerFactory.getLogger(MqttPushClient.class);
@Autowired
private PushCallback pushCallback;
private static MqttClient client;
private static MqttClient getClient() {
return client;
}
private static void setClient(MqttClient client) {
MqttPushClient.client = client;
}
/**
* 客户端连接
*
* @param host ip+端口
* @param clientID 客户端Id
* @param username 用户名
* @param password 密码
* @param timeout 超时时间
* @param keepalive 保留数
*/
public void connect(String host, String clientID, String username, String password, int timeout, int keepalive) {
MqttClient client;
try {
client = new MqttClient(host, clientID, new MemoryPersistence());
MqttConnectOptions options = new MqttConnectOptions();
options.setCleanSession(true);
options.setUserName(username);
options.setPassword(password.toCharArray());
options.setConnectionTimeout(timeout);
options.setKeepAliveInterval(keepalive);
MqttPushClient.setClient(client);
try {
client.setCallback(pushCallback);
client.connect(options);
} catch (Exception e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 发布
*
* @param qos 连接方式
* @param retained 是否保留
* @param topic 主题
* @param pushMessage 消息体
*/
public AjaxResult publish(int qos, boolean retained, String topic, String pushMessage) {
MqttMessage message = new MqttMessage();
message.setQos(qos);
message.setRetained(retained);
message.setPayload(pushMessage.getBytes());
MqttTopic mTopic = MqttPushClient.getClient().getTopic(topic);
if (null == mTopic) {
logger.error("topic not exist");
}
MqttDeliveryToken token;
try {
token = mTopic.publish(message);
token.waitForCompletion();
return AjaxResult.success();
} catch (MqttPersistenceException e) {
e.printStackTrace();
return AjaxResult.error();
} catch (MqttException e) {
e.printStackTrace();
return AjaxResult.error();
}
}
/**
* 订阅某个主题
*
* @param topic 主题
* @param qos 连接方式
*/
public void subscribe(String topic, int qos) {
logger.info("开始订阅主题" + topic);
try {
MqttPushClient.getClient().subscribe(topic, qos);
} catch (MqttException e) {
e.printStackTrace();
}
}
}
package com.ruoyi.common.utils.mqtt;
import com.alibaba.fastjson2.JSONObject;
import com.ruoyi.common.utils.MqttConfig;
import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import org.eclipse.paho.client.mqttv3.MqttCallback;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttMessage;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
@Component
public class PushCallback implements MqttCallback {
private static final Logger logger = LoggerFactory.getLogger(MqttPushClient.class);
@Autowired
private MqttConfig mqttConfig;
private static MqttClient client;
private static String _topic;
private static String _qos;
private static String _msg;
@Override
public void connectionLost(Throwable throwable) {
// 连接丢失后，一般在这里面进行重连
logger.info("连接断开，可以做重连");
if (client == null || !client.isConnected()) {
mqttConfig.getMqttPushClient();
}
}
@Override
public void messageArrived(String topic, MqttMessage mqttMessage) throws Exception {
// subscribe后得到的消息会执行到这里面
logger.info("接收消息主题 : " + topic);
logger.info("接收消息Qos : " + mqttMessage.getQos());
logger.info("接收消息内容 : " + new String(mqttMessage.getPayload()));
_topic = topic;
_qos = mqttMessage.getQos()+"";
_msg = new String(mqttMessage.getPayload());
}
/**
* 参数回调的方法
* @param iMqttDeliveryToken
*/
@Override
public void deliveryComplete(IMqttDeliveryToken iMqttDeliveryToken) {
logger.info("deliveryComplete---------" + iMqttDeliveryToken.isComplete());
}
//别的Controller层会调用这个方法来 获取 接收到的硬件数据
public String receive() {
JSONObject jsonObject = new JSONObject();
jsonObject.put("topic", _topic);
jsonObject.put("qos", _qos);
jsonObject.put("msg", _msg);
return jsonObject.toString();
}
}4、第四步修改emqx服务的白名单，去已经下载的emqx文件夹中打开到etc文件夹，打开acl.conf配置文件，修改里面的白名单
改完保存，重启emqx服务：命令： emqx restart
到这一步代码基本是已经集成完毕了
三：测试连接
1、打开浏览器，输入：http://ip:18083
18083端口是浏览器默认端口
1883是TCP协议端口
我是在本机启动的emqx服务所以用的是localhost，如果是线上的可以用线上的IP；
然后登录，账号：admin 密码：public
2、进入emqx服务之后连接websocket客户端
注意：端口号也要与项目配置的一样
全部连接之后就可以互相订阅了，在MqttPushClient.java文件中也有发送订阅的方法就留给你们自己测试了
若有不足伙计们请见谅
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