ONS发布订阅消息

ONS， 全名Open Notification Service, 是阿里基于开源消息中间件RocketMQ的一个云产品。

首先，要申请阿里账号等。本地也可以申请阿里云账号自己调试。此处为公司拥有阿里云服务，与运维op申请ons测试可用的服务。

申请ONS需要的创建topic，PID，CID，access_key，secret_key，要给产生access_key的账户授权发布订阅功能权限，具体请看其他配置阿里云账户权限的文章。

提供了这些以后，可以在官网查看ons快速入门文档创建简单的demo测试类调试生产和消费

使用ONS API发送订阅消息的示例

首先，pom引用ons-client

        <!-- RocketMq ons-client-->
        <dependency>
            <groupId>com.aliyun.openservices</groupId>
            <artifactId>ons-client</artifactId>
            <version>1.7.0.Final</version>
        </dependency>

第二步，配置消费者：

• 创建一个常量类存放

/**
 * 公共参数配置
 *
 */
public interface MqConfigParams {

    //测试ons配置文件
    public static final String TOPIC = "你申请下来的topic";
    public static final String TAG = "*";
    public static final String PRODUCER_ID = "你申请下来的pid";
    public static final String CONSUMER_ID = "你申请下来的cid";
    public static final String ACCESS_KEY = "你申请下来的accesskey";
    public static final String SECRET_KEY = "你申请下来的secretkey";
    public static final String ONS_ADDR = "http://onsaddr-internet.aliyun.com/rocketmq/nsaddr4client-internet";

}

• 创建一个生产者类，此处填入配置文件中的常量类，然后调用getproduce方法时启动生产者 producer.start();

import com.aliyun.openservices.ons.api.*;
import java.util.Date;
import java.util.Properties;

public class ONSUtil {

    /**
     * 获取消息的 Producer
     *
     * @return Producer
     */
    public static Producer getProducer() {
        Properties properties = new Properties();
        properties.put(PropertyKeyConst.ProducerId, MqConfigParams.PRODUCER_ID);
        properties.put(PropertyKeyConst.AccessKey, MqConfigParams.ACCESS_KEY);
        properties.put(PropertyKeyConst.SecretKey, MqConfigParams.SECRET_KEY);
        Producer producer = ONSFactory.createProducer(properties);

        // 在发送消息前，必须调用start方法来启动Producer，只需调用一次即可。
        producer.start();
        return producer;
    }
}　

• 封装一个发送消息的方法。

import com.aliyun.openservices.ons.api.Message;
import com.aliyun.openservices.ons.api.Producer;
import com.aliyun.openservices.ons.api.SendResult;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

@Service
public class OnsProducer {
    private final static Logger logger = LoggerFactory.getLogger(SeoLogController.class);

    public void sendMessage(String topic, String tag, String msgStr) {
        StringBuilder logsb = new StringBuilder("send OnsMQ Msg:");
        Message msg = getInstance(topic, tag, msgStr);
        String messageId = "";
        Producer producer = ONSUtil.getProducer(); //你申请的producerId
        SendResult sendResult = producer.send(msg);
        messageId = sendResult.getMessageId();
        if (messageId != null && !messageId.equals("")) {
            logsb.append("[OnsProducer] : " + "{ messageId : " + messageId + " , msgStr :" + msgStr + "}");
        } else {
            logsb.append("[OnsProducer] fail: " + "{ " + " msgStr :" + msgStr + "}");
        }
        logger.debug(logsb.toString());
    }

    private static Message getInstance(String topic, String tag, String body) {
        if (body.equals("") || body == null)
            body = "";
        Message msg = new Message(topic, tag, body.getBytes());
        return msg;
    }
}　　

这样就配置好了生产者。

调用生产者

可以写一个test类用main方法调试，示例这里是直接写main方法执行上面封装的内容直接执行看查看日志看是否成功

import com.aliyun.openservices.ons.api.Message;
import com.aliyun.openservices.ons.api.Producer;
import com.aliyun.openservices.ons.api.SendResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class TestSendMessage {
    private final static Logger logger = LoggerFactory.getLogger(TestSendMessage.class);
    public static void main(String[] args) {
        StringBuilder logsb = new StringBuilder("send OnsMQ Msg:");
        Producer producer = ONSUtil.getProducer(); //你申请的producerId
        Message msg = new Message(MqConfigParams.TOPIC, //你申请的TopicName
                "*","这是消息2".getBytes());
        SendResult sendResult = producer.send(msg);
        String messageId = "";
        messageId = sendResult.getMessageId();
        if (messageId != null || !messageId.equals("")) {
            logsb.append("[OnsProducer] : " + "{ messageId : " + messageId + " , msgStr :" + "这是消息2" + "}");
        } else {
            logsb.append("[OnsProducer] fail: " + "{ " + " msgStr :" + "这是消息2" + "}");
        }
        logger.debug(logsb.toString());
    }
}

    @RequestMapping(value = "/testmqProducer", method = RequestMethod.GET)
    public void testmq() {
         OnsProducer onsProducer=new OnsProducer();
         String msg = "testmq";
         onsProducer.sendMessage(MqConfigParams.TOPIC,"*",msg);
    }

接下来写消费者示例：

• 创建监听类实现MessageListener此处是处理业务逻辑因为此处可以得到消费的内容

import com.aliyun.openservices.ons.api.Action;
import com.aliyun.openservices.ons.api.ConsumeContext;
import com.aliyun.openservices.ons.api.Message;
import com.aliyun.openservices.ons.api.MessageListener;

import java.util.Date;

public class MyMessageListener implements MessageListener {
    @Override
    public Action consume(Message message, ConsumeContext consumeContext) {
        System.out.println("Receive @" + new Date() + ": " + message);
        //此处可以写具体业务逻辑，body是具体发送的内容
        String body = new String(message.getBody());
        System.out.println("msgBody is : " + body);
        return Action.CommitMessage;
    }
}　

• 创建消费者启动类和方法

import com.aliyun.openservices.ons.api.Consumer;
import com.aliyun.openservices.ons.api.ONSFactory;
import com.aliyun.openservices.ons.api.PropertyKeyConst;

import java.util.Date;
import java.util.Properties;

public class MyMessageConsumer {
    /**
     * 订阅消息
     */
    public void subscribe() {
        Properties properties = new Properties();
        properties.put(PropertyKeyConst.ConsumerId, MqConfigParams.CONSUMER_ID);
        properties.put(PropertyKeyConst.AccessKey, MqConfigParams.ACCESS_KEY);
        properties.put(PropertyKeyConst.SecretKey, MqConfigParams.SECRET_KEY);
        Consumer consumer = ONSFactory.createConsumer(properties);
        consumer.subscribe(MqConfigParams.TOPIC, "*", new MyMessageListener());//此处可以写父类messageListener但是必须实现方法这里就是用到了上面写的myMessageListener
        consumer.start();
        System.out.println(MqConfigParams.CONSUMER_ID + " is running @" + new Date());
    }
}

• 在Application启动类中加入消费者启动调用方法

@SpringBootApplication
@MapperScan("com.ons.test")
public class Application {
    public static void main(String[] args) {
        // 启动嵌入式的 Tomcat 并初始化 Spring 环境及其各 Spring 组件
        SpringApplication.run(Application.class,args);
        new MyMessageConsumer().subscribe(); // 系统启动的时候启动订阅
    }}