简介
MQTT:它构建在TCP/IP之上,用于受限制的设备和不可靠的网络,应用于许多(开放源码)代理实现和许多客户机库。它包含用于不良网络/连接的IoT特定特性,并被广泛使用(主要用于物联网,但也通过MQTT通过WebSockets用于web和移动应用程序)。
MQTT 安装
这里使用 Docker 一键安装:
docker run -d --name emqx -p 1883:1883 -p 8081:8081 -p 8083:8083 -p 8084:8084 -p 8883:8883 -p 18083:18083 emqx/emqx:4.3.5
默认账号 admin 密码 public
![null](https://filescdn.proginn.com/f29b67a828037eae1c3952634f41af08/ee10b29692fa32d28eb68577f8bd3123.webp)
整合
配置 pom.xml 引入:
<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>
配置 application.properties 引入:
spring.mqtt.username = admin
spring.mqtt.password = public
spring.mqtt.url = tcp://127.0.0.1:1883
spring.mqtt.client.id = HDC-DNC
spring.mqtt.default.topic = topic
spring.mqtt.default.completionTimeout = 3000
发送配置:
@Slf4j
@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("${spring.mqtt.default.topic}")
private String defaultTopic;
@Value("${spring.mqtt.default.completionTimeout}")
private int completionTimeout;
@Bean
public MqttConnectOptions getMqttConnectOptions() {
MqttConnectOptions mqttConnectOptions = new MqttConnectOptions();
mqttConnectOptions.setCleanSession(true);
mqttConnectOptions.setConnectionTimeout(10);
mqttConnectOptions.setKeepAliveInterval(90);
mqttConnectOptions.setAutomaticReconnect(true);
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();
}
}
接口服务:
@MessagingGateway(defaultRequestChannel = "mqttOutboundChannel")
public interface MqttGateway {
void sendToMqtt(String data, @Header(MqttHeaders.TOPIC) String topic);
}
源码:gitee.com/52itstyle/smart-parking
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