本文由 GXIC 作者 wongxmig 完成，欢迎关注 IoT 开发者社区。

1. 准备工作

1.1 注册阿里云账号

使用个人淘宝账号或手机号，开通阿里云账号，并通过__实名认证(可以用支付宝认证)__

1.2 免费开通IoT物联网套件

产品官网 https://www.aliyun.com/product/iot

1.3 软件环境

JDK安装
编辑器 IDEA

2. 开发步骤

2.1 云端开发

1) 创建高级版产品

2) 功能定义，产品物模型添加属性

添加产品属性定义

物模型对应属性上报topic

/sys/替换为productKey/替换为deviceName/thing/event/property/post

物模型对应的属性上报payload

{
    id: 123452452,
    params: {
        temperature: 26.2,
        humidity: 60.4
    },
    method: "thing.event.property.post"
}

3) 设备管理>注册设备，获得身份三元组

2.2 设备端开发

我们以java程序来模拟设备，建立连接，上报数据。

1) pom.xml添加sdk依赖

<dependencies>
        <dependency>
            <groupId>org.eclipse.paho</groupId>
            <artifactId>org.eclipse.paho.client.mqttv3</artifactId>
            <version>1.1.0</version>
        </dependency>
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>23.0</version>
        </dependency>
        
</dependencies>

2) AliyunIoTSignUtil工具类

import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.util.Arrays;
import java.util.Map;

/**
 * AliyunIoTSignUtil
 */

public class AliyunIoTSignUtil {
    public static String sign(Map<String, String> params, String deviceSecret, String signMethod) {
        //将参数Key按字典顺序排序
        String[] sortedKeys = params.keySet().toArray(new String[] {});
        Arrays.sort(sortedKeys);

        //生成规范化请求字符串
        StringBuilder canonicalizedQueryString = new StringBuilder();
        for (String key : sortedKeys) {
            if ("sign".equalsIgnoreCase(key)) {
                continue;
            }
            canonicalizedQueryString.append(key).append(params.get(key));
        }

        try {
            String key = deviceSecret;
            return encryptHMAC(signMethod,canonicalizedQueryString.toString(), key);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * HMACSHA1加密
     *
     */
    public static String encryptHMAC(String signMethod,String content, String key) throws Exception {
        SecretKey secretKey = new SecretKeySpec(key.getBytes("utf-8"), signMethod);
        Mac mac = Mac.getInstance(secretKey.getAlgorithm());
        mac.init(secretKey);
        byte[] data = mac.doFinal(content.getBytes("utf-8"));
        return bytesToHexString(data);
    }

    public static final String bytesToHexString(byte[] bArray) {

        StringBuffer sb = new StringBuffer(bArray.length);
        String sTemp;
        for (int i = 0; i < bArray.length; i++) {
            sTemp = Integer.toHexString(0xFF & bArray[i]);
            if (sTemp.length() < 2) {
                sb.append(0);
            }
            sb.append(sTemp.toUpperCase());
        }
        return sb.toString();
    }

}

3) 模拟设备IoTDemo.java代码

public class IoTDemo {

    public static String productKey = "替换productKey";
    public static String deviceName = "替换deviceName";
    public static String deviceSecret = "替换deviceSecret";
    public static String regionId = "cn-shanghai";

    //物模型-属性上报topic
    private static String pubTopic = "/sys/" + productKey + "/" + deviceName + "/thing/event/property/post";
    //高级版 物模型-属性上报payload
    private static final String payloadJson =
            "{" +
            "    \"id\": %s," +
            "    \"params\": {" +
            "        \"temperature\": %s," +
            "        \"humidity\": %s" +
            "    }," +
            "    \"method\": \"thing.event.property.post\"" +
            "}";

    private static MqttClient mqttClient;
    private static Random random = new Random();
    private static DecimalFormat df = new DecimalFormat("0.#");

    public static void main(String [] args) {

        initAliyunIoTClient();

        ScheduledExecutorService scheduledThreadPool = new ScheduledThreadPoolExecutor(1,
                new ThreadFactoryBuilder().setNameFormat("thread-runner-%d").build());

        scheduledThreadPool.scheduleAtFixedRate(()->postDeviceProperties(), 10,10, TimeUnit.SECONDS);

    }

    private static void initAliyunIoTClient() {

        try {
            String clientId = "java" + System.currentTimeMillis();

            Map<String, String> params = new HashMap<>(16);
            params.put("productKey", productKey);
            params.put("deviceName", deviceName);
            params.put("clientId", clientId);
            String timestamp = String.valueOf(System.currentTimeMillis());
            params.put("timestamp", timestamp);

            // cn-shanghai
            String targetServer = "tcp://" + productKey + ".iot-as-mqtt."+regionId+".aliyuncs.com:1883";

            String mqttclientId = clientId + "|securemode=3,signmethod=hmacsha1,timestamp=" + timestamp + "|";
            String mqttUsername = deviceName + "&" + productKey;
            String mqttPassword = AliyunIoTSignUtil.sign(params, deviceSecret, "hmacsha1");

            connectMqtt(targetServer, mqttclientId, mqttUsername, mqttPassword);

        } catch (Exception e) {
            System.out.println("initAliyunIoTClient error " + e.getMessage());
        }
    }

    public static void connectMqtt(String url, String clientId, String mqttUsername, String mqttPassword) throws Exception {

        MemoryPersistence persistence = new MemoryPersistence();
        mqttClient = new MqttClient(url, clientId, persistence);
        MqttConnectOptions connOpts = new MqttConnectOptions();
        // MQTT 3.1.1
        connOpts.setMqttVersion(4);
        connOpts.setAutomaticReconnect(false);
        connOpts.setCleanSession(true);

        connOpts.setUserName(mqttUsername);
        connOpts.setPassword(mqttPassword.toCharArray());
        connOpts.setKeepAliveInterval(60);

        mqttClient.connect(connOpts);

    }


    private static void postDeviceProperties() {

        try {

            //上报数据
            String payload = String.format(payloadJson, System.currentTimeMillis(), df.format(25+random.nextFloat()*10), df.format(50+random.nextFloat()*30));

            System.out.println("post :"+payload);

            MqttMessage message = new MqttMessage(payload.getBytes("utf-8"));
            message.setQos(1);

            mqttClient.publish(pubTopic, message);

        } catch (Exception e) {

        }

    }


}

3. 启动运行

3.1 设备启动

Run IoTDemo.main

3.2 云端查看设备运行状态

4. 项目源码

download: therometer.zip

download: aliyun-iot-demo-java.zip

<a class="anchor" id="" href="#80ifpi"></a>