设备影子状态不变

Question

尝试使用 manual 创建 aws-iot 设备。我在创建Pi3-DHT11-Node device 时完成了所有必需的设置。简化代码如下：

var awsIot = require('aws-iot-device-sdk'); 
const NODE_ID = 'Pi3-DHT11-Noded'; 
const INIT_DELAY = 15; 
const TAG = '[' + NODE_ID + '] >>>>>>>>> '; 

var thingShadow = awsIot.thingShadow({ 
  keyPath: './certs_p/fea2f8efae7-private.pem.key', 
  certPath: './certs_p/fea2f8efae7-certificate.pem.crt', 
  caPath: './certs_p/AmazonRootCA1.pem', 
  clientId: NODE_ID, 
  host: 'a3cnel9blokzm0-ats.iot.eu-west-3.amazonaws.com',
  port: 8883, 
  region: 'eu-west-3', 
  debug: true, // optional to see logs on console 
}); 

thingShadow.on('connect', function() { 
  console.log(TAG, 'Connected.'); 
  thingShadow.register(NODE_ID, {}, function() { 
    console.log(TAG, 'Registered.'); 
    console.log(TAG, 'Reading data in ' + INIT_DELAY + ' seconds.'); 
    setTimeout(sendData, INIT_DELAY * 1000); // wait for `INIT_DELAY` seconds before reading the first record 
  }); 
}); 

function sendData() { 
  var DHT11State = { 
    "state": { 
      "desired": 
        { 
        "temp": 20, 
        "humd": 33 
        }
    } 
  }; 

  var clientTokenUpdate = thingShadow.update(NODE_ID, DHT11State); 
  if (clientTokenUpdate === null) { 
    console.log(TAG, 'Shadow update failed, operation still in progress'); 
  } else { 
    console.log(TAG, 'Shadow update success.'); 
  } 

  // keep sending the data every 30 seconds 
  console.log(TAG, 'Reading data again in 30 seconds.'); 
  setTimeout(sendData, 30000); // 30,000 ms => 30 seconds 
} 

脚本工作正常，但这不会改变阴影状态。为什么？如何解决？

Answer 1

很可能您没有将影子同步到云端的设备设置。

按照本教程这一部分中的步骤操作，并确保按照第 2 步单击“同步到云”，然后重新部署您的 Greengrass 组。

https://docs.aws.amazon.com/greengrass/latest/developerguide/comms-enabled.html