将 AWS IoT 的 ThingShadow 与 Websocket 连接一起使用

Question

当我第一次开始学习如何使用 aws 时，我通过转到 AWS IoT 管理控制台并创建“事物”将我的设备/thingShadow 连接到 IoT 核心。每个事物都附带一个私有、公共和证书密钥，您可以通过执行以下操作来连接到 IoT：

var awsIot = require('aws-iot-device-sdk');

const keyPath = `./260b380cc2-private.pem.key`
const certPath = `./260b380cc2-certificate.pem.crt`
const caPath = './rootCA.pem'
const clientId = 'client'
const host = 'XXXXXXXXXXXXXXXX.iot.us-east-2.amazonaws.com'

var thingShadow = awsIot.thingShadow({
    keyPath: keyPath,
   certPath: certPath,
     caPath: caPath,
   clientId: clientId,
       host: host
 });

 var shadowName = 'testShadow'
 
 thingShadow.on("connect", () => {
    thingShadow.register(shadowName, {}, () => {

        console.log("Conneced. Getting shadow")        
        thingShadow.get(shadowName)
    })
})

thingShadow.on('status',
    function(thingName, stat, clientToken, stateObject) {

       console.log('received '+stat+' on '+thingName+': '+
                   JSON.stringify(stateObject))})

现在，我不是使用 RSA 密钥连接到 IoT Core，而是使用 Amazon 的 Cognito 身份池通过 websocket 协议连接设备：

Aws = require('aws-sdk/dist/aws-sdk-react-native');
awsIot = require('aws-iot-device-sdk');

const AWS_REGION = 'us-east-2';
const AWS_COGNITO_IDENTITY_POOL = 'us-east-2:XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX';
const AWS_IOT_ENDPOINT = 'XXXXXXXXXXXXXX.iot.us-east-2.amazonaws.com';

Aws.config.region = AWS_REGION
Aws.config.credentials = new Aws.CognitoIdentityCredentials({
    IdentityPoolId: AWS_COGNITO_IDENTITY_POOL
})

Aws.config.credentials.get(() => {
    const config = {}
    let client
    
    config.host = AWS_IOT_ENDPOINT
    config.protocol = 'wss'
    config.clientId = `client-${Math.floor((Math.random() * 100000) + 1)}`
    config.accessKeyId = 'XXXXXXXXXXXXXX';
    config.secretKey = 'XXXXXXXXXXXXXXXXXXXXXX';
    
    //client = awsIot.device(config)
    client = awsIot.thingShadow(config);
    
    client.on('connect', (success) => {
        if (success) {
            console.log("Connected.")
            client.register('testShadow')
            client.get('testShadow')

        } else {
            console.log("Could not connect.")
        }
       
    })

    client.on('close', () => {
        console.log("Connection closed.")
    })
    
    client.on('message', (topic, message) => {
        console.log(topic, message)
    })

    client.on("status", (shadow, stat, id, state) => {
        console.log(JSON.stringify(state))
    })
    
    client.on('error', error => {
        console.log(error)
    })
})

第二个代码块的问题是，当我使用client = awsIoT.thingShadow(config)时，客户端无法连接并打印Could not connect. 但是当我使用client = awsIot.device(config)时，客户端连接并打印出Connected（当我使用aws.Iot.device，我不包括 client.register 和 client.get 代码行）。除此之外，我没有收到任何类型的错误，所以我不确定为什么它无法连接或我应该做什么，以便我可以通过 cognito 身份池获得一个 thingShadow 来连接。甚至可能吗？如果是，我怎样才能获得这种功能？

Answer 1

您在 WS 示例中使用的 AWS IAM 凭证是否具有访问设备影子所需的 permissions？