MQTT是一个轻量级的消息发布/订阅协议,它是实现基于手机客户端的消息推送服务器的理想解决方案。

        实现MQTT协议的中间件有很多,我用的是Apollo服务器,如何搭建MQTT服务器,请查阅其他资料。这里,主要介绍SpringBoot2.0集成MQTT实现消息推送的功能。好,正式开始:

        本文采用Gateway绑定的方式,网上也有介绍但不全面,还有其他采用Paho MQTT Client库的方式实现的。

-------------------------------------------------------------------------消息推送--------------------------------------------------------------------------------------

         第一,pom配置,我们需要引入相关jar:        

 

<dependency>
    <groupId>org.springframework.integration</groupId>
    <artifactId>spring-integration-stream</artifactId>
</dependency>
<dependency>
   <groupId>org.springframework.integration</groupId>
   <artifactId>spring-integration-mqtt</artifactId>
</dependency>


        第二,配置MQTT服务器基本信息,

在springBoot配置文件application.properties中配置,添加如下:

 

#MQTT配置信息
#MQTT-用户名
spring.mqtt.username=admin
#MQTT-密码
spring.mqtt.password=password
#MQTT-服务器连接地址,如果有多个,用逗号隔开,如:tcp://127.0.0.1:61613,tcp://192.168.2.133:61613
spring.mqtt.url=tcp://127.0.0.1:61613
#MQTT-连接服务器默认客户端ID
spring.mqtt.client.id=mqttId
#MQTT-默认的消息推送主题,实际可在调用接口时指定
spring.mqtt.default.topic=topic


    第三,配置MQTT消息推送配置类

/**
 * 〈一句话功能简述〉<br> 
 * 〈MQTT发送消息配置〉
 *
 * @author AnswerChang
 * @create 2018/6/4
 * @since 1.0.0
 */
@Configuration
@IntegrationComponentScan
public class MqttSenderConfig {
 
    @Value("${spring.mqtt.username}")
    private String username;
 
    @Value("${spring.mqtt.password}")
    private String password;
 
    @Value("${spring.mqtt.url}")
    private String hostUrl;
 
    @Value("${spring.mqtt.client.id}")
    private String clientId;
 
    @Value("${spring.mqtt.default.topic}")
    private String defaultTopic;
 
    @Bean
    public MqttConnectOptions getMqttConnectOptions(){
        MqttConnectOptions mqttConnectOptions=new MqttConnectOptions();
        mqttConnectOptions.setUserName(username);
        mqttConnectOptions.setPassword(password.toCharArray());
        mqttConnectOptions.setServerURIs(new String[]{hostUrl});
        mqttConnectOptions.setKeepAliveInterval(2);
        return mqttConnectOptions;
    }
    @Bean
    public MqttPahoClientFactory mqttClientFactory() {
        DefaultMqttPahoClientFactory factory = new DefaultMqttPahoClientFactory();
        factory.setConnectionOptions(getMqttConnectOptions());
        return factory;
    }
    @Bean
    @ServiceActivator(inputChannel = "mqttOutboundChannel")
    public MessageHandler mqttOutbound() {
        MqttPahoMessageHandler messageHandler =  new MqttPahoMessageHandler(clientId, mqttClientFactory());
        messageHandler.setAsync(true);
        messageHandler.setDefaultTopic(defaultTopic);
        return messageHandler;
    }
    @Bean
    public MessageChannel mqttOutboundChannel() {
        return new DirectChannel();
    }
}


        第四,配置MqttGateway消息推送接口类

在sendToMqtt(String data,@Header(MqttHeaders.TOPIC)String topic)接口中,data为发送的消息内容,topic为主题。指定topic,则我们的接口可以根据需要,向不同的主题发送消息,方便灵活应用。如果不指定,则使用默认配置的主题。

 

@MessagingGateway(defaultRequestChannel = "mqttOutboundChannel")
public interface MqttGateway {
    void sendToMqtt(String data,@Header(MqttHeaders.TOPIC) String topic);
}
        最后,写个接口类测试下功能,用Postman调用sendMqtt.do接口,往hello主题发送消息,用MQTTLens订阅hello主题,从下面截图,可以看出可以正常往MQTT服务发送消息了,而且可以订阅到。

 

@RestController
@RequestMapping("/test")
public class TestController {
 
    @Autowired
    private MqttGateway mqttGateway;
 
    @RequestMapping("/sendMqtt.do")
    public String sendMqtt(String  sendData){
        mqttGateway.sendToMqtt(sendData,"hello");
        return "OK";
    }
}

-------------------------------------------------------------------------消息订阅--------------------------------------------------------------------------------------

 第一,pom配置,引入相关jar:

<dependency>
    <groupId>org.springframework.integration</groupId>
    <artifactId>spring-integration-stream</artifactId>
</dependency>
<dependency>
   <groupId>org.springframework.integration</groupId>
   <artifactId>spring-integration-mqtt</artifactId>
</dependency>    


第二,配置MQTT服务器基本信息

在springBoot配置文件application.properties中配置,添加如下:

#MQTT配置信息
#MQTT-用户名
spring.mqtt.username=admin
#MQTT-密码
spring.mqtt.password=password
#MQTT-服务器连接地址,如果有多个,用逗号隔开,如:tcp://127.0.0.1:61613,tcp://192.168.2.133:61613
spring.mqtt.url=tcp://127.0.0.1:61613
#MQTT-连接服务器默认客户端ID
spring.mqtt.client.id=mqttId
#MQTT-默认的消息推送主题,实际可在调用接口时指定
spring.mqtt.default.topic=topic
#连接超时
spring.mqtt.completionTimeout=3000


第三,配置MQTT消息接收处理类:

/**
 * 〈一句话功能简述〉<br> 
 * 〈MQTT接收消息处理〉
 *
 * @author lenovo
 * @create 2018/6/4
 * @since 1.0.0
 */
@Configuration
@IntegrationComponentScan
public class MqttReceiveConfig {
 
    @Value("${spring.mqtt.username}")
    private String username;
 
    @Value("${spring.mqtt.password}")
    private String password;
 
    @Value("${spring.mqtt.url}")
    private String hostUrl;
 
    @Value("${spring.mqtt.client.id}")
    private String clientId;
 
    @Value("${spring.mqtt.default.topic}")
    private String defaultTopic;
 
    @Value("${spring.mqtt.completionTimeout}")
    private int completionTimeout ;   //连接超时
 
 
    @Bean
    public MqttConnectOptions getMqttConnectOptions(){
        MqttConnectOptions mqttConnectOptions=new MqttConnectOptions();
        mqttConnectOptions.setUserName(username);
        mqttConnectOptions.setPassword(password.toCharArray());
        mqttConnectOptions.setServerURIs(new String[]{hostUrl});
        mqttConnectOptions.setKeepAliveInterval(2);
        return mqttConnectOptions;
    }
    @Bean
    public MqttPahoClientFactory mqttClientFactory() {
        DefaultMqttPahoClientFactory factory = new DefaultMqttPahoClientFactory();
        factory.setConnectionOptions(getMqttConnectOptions());
        return factory;
    }
 
    //接收通道
    @Bean
    public MessageChannel mqttInputChannel() {
        return new DirectChannel();
    }
 
    //配置client,监听的topic 
    @Bean
    public MessageProducer inbound() {
        MqttPahoMessageDrivenChannelAdapter adapter =
                new MqttPahoMessageDrivenChannelAdapter(clientId+"_inbound", mqttClientFactory(),
                        "hello","hello1");
        adapter.setCompletionTimeout(completionTimeout);
        adapter.setConverter(new DefaultPahoMessageConverter());
        adapter.setQos(1);
        adapter.setOutputChannel(mqttInputChannel());
        return adapter;
    }
 
    //通过通道获取数据
    @Bean
    @ServiceActivator(inputChannel = "mqttInputChannel")
    public MessageHandler handler() {
        return new MessageHandler() {
            @Override
            public void handleMessage(Message<?> message) throws MessagingException {
                String topic = message.getHeaders().get("mqtt_receivedTopic").toString();
                String type = topic.substring(topic.lastIndexOf("/")+1, topic.length());
                if("hello".equalsIgnoreCase(topic)){
                    System.out.println("hello,fuckXX,"+message.getPayload().toString());
                }else if("hello1".equalsIgnoreCase(topic)){
                    System.out.println("hello1,fuckXX,"+message.getPayload().toString());
                }
            }
        };
    }
}

第四,启动服务测试

使用postment调用上一篇的MQTT发送接口,分别往hello,hello1两个topic发送消息,测试接收情况:

        由此看出,可以正常监听topic并接收处理消息了。

        看到这里,朋友们可能有疑问,如果我要配置多个client,应该怎么处理呢?这个也简单,我们只要配置多个通道即可,简单代码如下:

//通道2
@Bean
public MessageChannel mqttInputChannelTwo() {
    return new DirectChannel();
}
//配置client2,监听的topic:hell2,hello3
@Bean
public MessageProducer inbound1() {
    MqttPahoMessageDrivenChannelAdapter adapter =
            new MqttPahoMessageDrivenChannelAdapter(clientId+"_inboundTwo", mqttClientFactory(),
                    "hello2","hello3");
    adapter.setCompletionTimeout(completionTimeout);
    adapter.setConverter(new DefaultPahoMessageConverter());
    adapter.setQos(1);
    adapter.setOutputChannel(mqttInputChannelTwo());
    return adapter;
}
 
//通过通道2获取数据
@Bean
@ServiceActivator(inputChannel = "mqttInputChannelTwo")
public MessageHandler handlerTwo() {
    return new MessageHandler() {
        @Override
        public void handleMessage(Message<?> message) throws MessagingException {
            String topic = message.getHeaders().get("mqtt_receivedTopic").toString();
            String type = topic.substring(topic.lastIndexOf("/")+1, topic.length());
            if("hello2".equalsIgnoreCase(topic)){
                System.out.println("hello2 clientTwo,"+message.getPayload().toString());
            }else if("hello3".equalsIgnoreCase(topic)){
                System.out.println("hello3 clientTwo,"+message.getPayload().toString());
            }
        }
    };
}
        这样一来,我们就配置了两个client,client1监听处理hello、hello1主题消息,client2监听处理hello2、hello3主题,测试一下:

         从输出结果可以看出,我们发送不同的消息,分别由不同的client处理。所以,小伙伴,你理解了吗?
 

Logo

权威|前沿|技术|干货|国内首个API全生命周期开发者社区

更多推荐