Kubeedge-mapper 实现

时间 2020-05-22

标签 kubeedge mapper 实现繁體版

原文原文链接

应用场景：

利用GitHub上的温度传感器的例子做为讲解，实现从云端获取设备终端状态及使用Java模拟设备数据。其实和官网给的视频同样，只须要将终端设备的数据转换为支持MQTT协议传输的数据，云端就能够拿到数据了。java

须要使用的文件及技术

1.云端：建立文件，及开启cloudCorenode

vim device.yaml    //案例中的设备配置，直接使用请删除全部注释
#apiVersion,该属性定义了咱们从k8s获取改设备数据的url路径
apiVersion: devices.kubeedge.io/v1alpha1  
kind: Device
metadata:
  name: temperature3
  labels:
    description: 'temperature3'
    manufacturer: 'test'
spec:
  deviceModelRef:
    name: temperature3-model    #与设备模板名称进行绑定
  nodeSelector:
    nodeSelectorTerms:
      - matchExpressions:
          - key: ''
            operator: In
            values:
              - sunsheen-edge   #部署该设备的节点
# status中的属性为咱们能够定义的属性，属性名为propertyName的属性与初始指望值
status:    
  twins:
    - propertyName: temperatureState
      desired:
        metadata:
          type: string
        value: 'on'
    - propertyName: temperature
      desired:
        metadata:
          type: string
        value: ''

vim devicemodel.yaml   //设备模板文件，直接使用请删除全部注释。
#apiVersion与设备端保持一致
apiVersion: devices.kubeedge.io/v1alpha1
kind: DeviceModel
metadata:
  name: temperature3-model
  namespace: default
spec:
#属性与设备的保持一致，这里能够设备权限，这里咱们只能修改温度状态，没法控制实际温度
  properties:
    - name: temperatureState
      description: Temperature collected from the edge device
      type:
        string:
          accessMode: ReadWrite
          defaultValue: 'on'
    - name: temperature
      description: Temperature collected from the edge device
      type:
        string:
          accessMode: ReadOnly
          defaultValue: ''

vim deployment.yaml  //使用deployment控制器(k8s内容)， 建立POD，边缘节点会自动去拉取镜像（很慢，建议手动拉取，或配置私有镜像仓库）

apiVersion: apps/v1
kind: Deployment
metadata:
  name: temperature3-mapper
  labels:
    app: temperature
spec:
  replicas: 1
  selector:
    matchLabels:
      app: temperature3
  template:
    metadata:
      labels:
        app: temperature3
    spec:
      hostNetwork: true
      nodeSelector:
        name: "sunsheen-edge"
      containers:
      - name: temperature3
        image: kubeedge-mapper:v2.2    #须要部署的镜像
        imagePullPolicy: IfNotPresent
        securityContext:
          privileged: true

2.边缘端：开启 mosquitto，启动edgeCoredocker

mosquitto -d -p 1883  //边缘端开启mosquitto，用于传输消息

JAVA代码模拟设备推送接收与推送消息：

<dependency>
            <groupId>org.yaml</groupId>
            <artifactId>snakeyaml</artifactId>
            <version>1.13</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.58</version>
        </dependency>
        <!--   http请求     -->
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient-cache</artifactId>
            <version>4.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpmime</artifactId>
            <version>4.5.2</version>
        </dependency>

        <dependency>
            <groupId>org.eclipse.paho</groupId>
            <artifactId>org.eclipse.paho.client.mqttv3</artifactId>
            <version>1.2.0</version>
        </dependency>

import java.util.concurrent.ScheduledExecutorService;

import org.eclipse.paho.client.mqttv3.*;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;

/**
 * @author wanchen.chen
 * @ClassName KubeedageClient
 * @Despriction: MQTTP 链接类，用于推送/订阅 消息
 * @date 2020/4/15 9:20
 * @Version 1.0
 **/
public class KubeedageClient {

    private MqttMessage message;
    private MqttClient client;
    private MqttConnectOptions options;
    private MqttTopic clientTopic;
    private MqttTopic serverTopic;
    //定义主题，document为云端反馈的主题；update为边缘向云端推送的主题。temperature3为设备名称，其余都固定。
    private static String clientTopicStr ="$hw/events/device/temperature3/twin/update/document";
    private static String serverTopicStr ="$hw/events/device/temperature3/twin/update";
    private static final String url ="tcp://0.0.0.0:1883";
    //我这里是要打包为镜像部署，全部须要配置边缘节点的用户及密码
    private static final String userName ="xxx";
    private static final String password ="xxx";

    private ScheduledExecutorService scheduler;

    public KubeedageClient(){
    }

    /**
     * 初始化
     */
    public void start() {
        try {
            // host为主机名，clientid即链接MQTT的客户端ID，通常以惟一标识符表示，MemoryPersistence设置clientid的保存形式，默认为之内存保存
            client = new MqttClient(url, "KubeEdgeClient", new MemoryPersistence());
            // MQTT的链接设置
            options = new MqttConnectOptions();
            // 设置是否清空session,这里若是设置为false表示服务器会保留客户端的链接记录，这里设置为true表示每次链接到服务器都以新的身份链接
            options.setCleanSession(true);
            // 设置链接的用户名
            options.setUserName(userName);
            // 设置链接的密码
            options.setPassword(password.toCharArray());
            // 设置超时时间 单位为秒
            options.setConnectionTimeout(10);
            // 设置会话心跳时间 单位为秒 服务器会每隔1.5*20秒的时间向客户端发送个消息判断客户端是否在线，但这个方法并无重连的机制
            options.setKeepAliveInterval(20);
            // 设置回调
            client.setCallback(new PushCallback());
            clientTopic = client.getTopic(clientTopicStr);
            serverTopic = client.getTopic(serverTopicStr);
            //setWill方法，若是项目中须要知道客户端是否掉线能够调用该方法。设置最终端口的通知消息
//            options.setWill(clientTopoc, "close".getBytes(), 2, true);
            client.connect(options);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 订阅主题消息
     */
    public void listerData(){
        //订阅消息
        int[] Qos  = {1};
        String[] topic1 = {clientTopicStr};
        try {
            client.subscribe(topic1, Qos);
        } catch (MqttException e) {
            e.printStackTrace();
        }
    }

    /**
     * push 消息到主题
     * @param topic
     * @param message
     * @throws MqttPersistenceException
     * @throws MqttException
     */
    public void publish(MqttTopic topic , MqttMessage message) throws MqttPersistenceException,
            MqttException {
        MqttDeliveryToken token = topic.publish(message);
        token.waitForCompletion();
//        System.out.println("message is published completely! "
//                + token.isComplete());
    }

    /**
     * 发送消息
     * @param deviceInfo
     */
    public void putData(String deviceInfo){
        message = new MqttMessage();
        message.setQos(2);
        message.setRetained(true);
        message.setPayload(deviceInfo.getBytes());
        try {
            publish(serverTopic,message);
        } catch (MqttException e) {
            e.printStackTrace();
        }
    }

}

import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import org.eclipse.paho.client.mqttv3.MqttCallback;
import org.eclipse.paho.client.mqttv3.MqttMessage;

/**
 * @author wanchen.chen
 * @ClassName PushCallback 发布消息的回调类
 * @Despriction: 必须实现MqttCallback的接口并实现对应的相关接口方法CallBack 类将实现 MqttCallBack。
 *  每一个客户机标识都须要一个回调实例。在此示例中，构造函数传递客户机标识以另存为实例数据。
 *  在回调中，将它用来标识已经启动了该回调的哪一个实例。
 *  必须在回调类中实现三个方法：
 * @date 2020/4/15 9:17
 * @Version 1.0
 **/
public class PushCallback implements MqttCallback {

    public void connectionLost(Throwable cause) {
        // 链接丢失后，通常在这里面进行重连
        System.out.println("链接断开，能够作重连");
    }

    public void deliveryComplete(IMqttDeliveryToken token) {
        System.out.println("deliveryComplete---------" + token.isComplete());
    }

    public void messageArrived(String topic, MqttMessage message) throws Exception {
        // subscribe后获得的消息会执行到这里面,消息只能被消费一次
        System.out.println("接收消息主题 : " + topic);
        System.out.println("接收消息Qos : " + message.getQos());
        System.out.println("接收的消息为："+str);
    }

}

发送的消息结构：

.yaml文件，用于json数据结构apache

event_id: 0
timestamp: 0
twin:
  temperature:
    actual:
      value: 0
    metadata:
      type: Updated
  temperatureState:
    actual:
      value: height
    metadata:
      type: Updated

经过Java代码将其转换为JSON，将数据put进JSON中就能够发送了：json

import org.yaml.snakeyaml.Yaml;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.net.URL;
import java.util.Map;

/**
 * @author wanchen.chen
 * @ClassName AnalysisYAML
 * @Despriction: 解析YAML文件的内容
 * @date 2020/4/28 9:32
 * @Version 1.0
 **/
public class AnalysisYAML {

    /**
     * 传参解析
     * @param urlStr
     * @return
     */
    public  Map<String,Object> getYamlData(String urlStr){
        URL url = AnalysisYAML.class.getClassLoader().getResource(urlStr);
        return analysisData(url);
    }

    /**
     * 默认解析
     * @return
     */
    public  Map<String,Object> getYamlData(){
        URL url = AnalysisYAML.class.getClassLoader().getResource("attribute.yaml");
        return analysisData(url);
    }

    /**
     * 获取URL 解析内容
     * @param url
     * @return
     */
    public Map<String,Object> analysisData(URL url){
        InputStream input = null;
        try {
            input = new FileInputStream(url.getFile());
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        Yaml yaml = new Yaml();
        Map<String,Object> map = (Map<String,Object>)yaml.load(input);
        return map;
    }
}

镜像打包：

经过DockerFile将jar文件打包为镜像：vim

FROM java:latest
RUN mkdir -p /usr
RUN mkdir -p /usr/local
COPY . /usr/local/
WORKDIR /usr/local
EXPOSE 8892
ENTRYPOINT ["java","-jar","xxx.jar"]

//在DockerFile 文件目录下建立镜像
docker build -t kubeedge-mapper:v2.0 .