Authentication and connection

API description

• Prototype: iot.device(options)
• Description: Creates a device instance and connects it to Alibaba Cloud IoT Platform.
• Request parameters:

  Parameter	Type	Description
  brokerUrl	String	The server URI of the MQTT broker. The default value is mqtt://${productKey}.iot-as-mqtt.cn-shanghai.aliyuncs.com:1883/. In the URI, ${productKey} is the ProductKey of your device.
  productKey	String	The authentication credentials of the device. For more information, see Obtain device credentials.
  deviceName	String
  deviceSecret	String
  regionId	String	The ID of the region where the device is connected. For more information, see Regions and zones.
  keepalive	Integer	The heartbeat interval for the keepalive connection between the device and IoT Platform. The default value is 60 seconds.
  clean	Boolean	Specifies whether to clear the connection session. Valid values: true: yes false (default): no

• Return value: An MQTT client connection instance.
• The following events are triggered:
  • connect: The device successfully connects to IoT Platform.
  • offline: The device disconnects from IoT Platform.
  • message: The device receives a message from IoT Platform.
  • error: An error occurs. For example, the device credentials are incorrect.

Set the connection region

Alibaba Cloud IoT Platform is available in multiple regions. The default region for the SDK is China (Shanghai). For more information, see Regions and zones.

When you use the SDK to connect a device, you can set the regionId parameter to connect the device to a specific region. The following sample code sets the region to ap-northeast-1, which is Asia Pacific NE 1 (Tokyo).

// Import the package in Node.js
const iot = require('alibabacloud-iot-device-sdk');
const device = iot.device({
  productKey: `${productKey}`,
  deviceName: `${deviceName}`,
  deviceSecret: `${deviceSecret}`,
  regionId: 'ap-northeast-1'
});
​
device.on('connect', () => {
  console.log('connect successfully!');
})

Set the MQTT broker server URI

The format is schema://host:port.

• host is the connection domain name of the device. For more information, see Obtain device credentials.

  The following are examples of host:

  • For an Enterprise instance or a public instance of an IoT Platform service activated on or after July 30, 2021: iot-06******.mqtt.iothub.aliyuncs.com

    In this example, iot-06****** is the instance ID.

  • For a public instance of an IoT Platform service activated before July 30, 2021: a1BOO******.iot-as-mqtt.cn-shanghai.aliyuncs.com

    In the domain name, a1BOO****** is the ProductKey of your device.

• schema can be ws, wss, tcp, unix, ssl, tls, or tcps.

const iot = require('alibabacloud-iot-device-sdk');
const device = iot.device({
  productKey: `${productKey}`,
  deviceName: `${deviceName}`,
  deviceSecret: `${deviceSecret}`,
  brokerUrl: `wss://${productKey}.iot-as-mqtt.${regionId}.aliyuncs.com:443`,
});
​
device.on('connect', () => {
  console.log('connect successfully!');
});

Unique-certificate-per-device

const iot = require('alibabacloud-iot-device-sdk');
​
// Creating an iot.device object initiates a connection to Alibaba Cloud IoT.
const device = iot.device({
  productKey: `${productKey}`, //Replace ${productKey} with the actual ProductKey of your product.
  deviceName: `${deviceName}`,//Replace ${deviceName} with the actual DeviceName of your device.
  deviceSecret: `${deviceSecret}`,//Replace ${deviceSecret} with the actual DeviceSecret of your device.
});
​
// Listen for the connect event.
device.on('connect', () => {
  //Replace ${productKey} and ${deviceName} with the actual values.
  device.subscribe(`/${productKey}/${deviceName}/user/get`);
  console.log('connect successfully!');
  device.publish(`/${productKey}/${deviceName}/user/update`, 'hello world!');
});
​
// Listen for the message event.
device.on('message', (topic, payload) => {
  console.log(topic, payload.toString());
});        

Unique-certificate-per-product

const iot = require('alibabacloud-iot-device-sdk');
const params = {
  productKey: `${productKey}`,
  productSecret: `${productSecret}`,
  deviceName: `${deviceName}`
};
let device;
iot.register(params, (res) => {
  console.log("register:", res);
  if (res.code == '200') {
    // res.data.deviceSecret is the device secret returned by IoT Platform. Securely store this secret.
    // After the device successfully connects to IoT Platform using its credentials, you cannot use this function again to obtain the DeviceSecret.
    // Create a device object to connect to Alibaba Cloud IoT Platform.
    device = iot.device({
      productKey: `${productKey}`,
      deviceName: `${deviceName}`,
      // res.data.deviceSecret is the device secret returned by IoT Platform.
      deviceSecret: res.data.deviceSecret,
    });
  }
});

• For the complete sample code for unique-certificate-per-product authentication, see one_model_one_secret.js.
• res.code:

  Value	Description
  200	The DeviceSecret is obtained.
  5005	Invalid product. The ProductKey provided by the device is incorrect.
  6100	Invalid device. No device with the specified deviceName exists in IoT Platform.
  6288	The product does not support dynamic registration. Enable dynamic registration for the product in IoT Platform.
  6289	The device is already activated and cannot be registered again. Note A device certificate can be used to activate only one physical device. If Device A is activated by using a DeviceName but Device B must use the DeviceName, you can delete Device A in the IoT Platform console and disable the DeviceSecret of Device A. This way, you can use the DeviceName to add and activate Device B. If a device needs to be reactivated because the DeviceSecret is lost, you must call the ResetThing operation to reset the device status to Inactive. Then, you can reactivate the device. In this case, the DeviceSecret that is issued by IoT Platform remains unchanged.
  6600	Verification error. The ProductSecret of the device is incorrect.

Disconnect from the cloud

To disconnect from IoT Platform, call the end function.

const iot = require('alibabacloud-iot-device-sdk');
const device = iot.device({
  productKey: `${productKey}`,
  deviceName: `${deviceName}`,
  deviceSecret: `${deviceSecret}`,
});
​
/*Disconnect from Alibaba Cloud IoT Platform*/
device.end();