Fetch twin from Azure device sdk

Question

I need to just get the twin of a device using the Azure device sdk for node.js. I did used the Client clode as below:-

import { Client } from 'azure-iot-device';
import { Mqtt } from 'azure-iot-device-mqtt';
await client.setOptions(options);
await client.open();
const twin = await client.getTwin();

The issue is the twin returned doesn't have the device twin fields but other fields like below:-

{
  _events: [Object: null prototype] { newListener: [Function: bound ] },
  _eventsCount: 1,
  _maxListeners: undefined,
  _transport: Mqtt {
    _events: [Object: null prototype] {
      error: [Function],
      connected: [Function],
      disconnect: [Array],
      message: [Function],
      twinDesiredPropertiesUpdate: [Function: bound ]
    },
    _eventsCount: 5,
    _maxListeners: undefined,
    _mid: '',
    _firstConnection: false,
    _authenticationProvider: X509AuthenticationProvider { type: 0, _credentials: [Object] },
    _mqtt: MqttBase {
      _events: [Object: null prototype],
      _eventsCount: 2,
      _maxListeners: undefined,
      mqttProvider: [Object],
      _onTheWirePublishes: [OnTheWireMessageContainer],
      _fsm: [constructor],
      _options: [Object],
      _config: [Object],
      _mqttClient: [MqttClient],
      [Symbol(kCapture)]: false
    },
    _twinClient: MqttTwinClient {
      _events: [Object: null prototype],
      _eventsCount: 1,
      _maxListeners: undefined,
      _pendingTwinRequests: {},
      _mqtt: [MqttBase],
      _topicFsm: [BehavioralFsm],
      _responseTopic: [Object],
      _desiredPropertiesUpdatesTopic: [Object],
      [Symbol(kCapture)]: false
    },
    _fsm: constructor {
      initialState: 'disconnected',
      states: [Object],
      eventListeners: [Object],
      namespace: 'fsm.2',
      useSafeEmit: false,
      hierarchy: {},
      pendingDelegations: {},
      _stamped: true,
      inputQueue: [],
      targetReplayState: 'connected',
      state: 'connected',
      priorState: 'connecting',
      priorAction: 'connected.getTwin',
      currentAction: '',
      currentActionArgs: undefined,
      inExitHandler: false
    },
    _topicTelemetryPublish: 'devices/amidha/messages/events/',
    _topics: { method: [Object], message: [Object] },
    _userAgentString: 'azure-iot-device/1.17.1 (node v12.18.0; Ubuntu 18.04; x64)',
    [Symbol(kCapture)]: false
  },
  _retryPolicy: ExponentialBackOffWithJitter {
    _errorFilter: DefaultErrorFilter {
      ArgumentError: false,
      ArgumentOutOfRangeError: false,
      DeviceMaximumQueueDepthExceededError: false,
      DeviceNotFoundError: false,
      FormatError: false,
      UnauthorizedError: false,
      NotImplementedError: false,
      NotConnectedError: true,
      IotHubQuotaExceededError: false,
      MessageTooLargeError: false,
      InternalServerError: true,
      ServiceUnavailableError: true,
      IotHubNotFoundError: false,
      IoTHubSuspendedError: false,
      JobNotFoundError: false,
      TooManyDevicesError: false,
      ThrottlingError: true,
      DeviceAlreadyExistsError: false,
      DeviceMessageLockLostError: false,
      InvalidEtagError: false,
      InvalidOperationError: false,
      PreconditionFailedError: false,
      TimeoutError: true,
      BadDeviceResponseError: false,
      GatewayTimeoutError: false,
      DeviceTimeoutError: false,
      TwinRequestError: false
    },
    immediateFirstRetry: true,
    normalParameters: ExponentialBackoffWithJitterParameters {
      c: 100,
      cMin: 100,
      cMax: 10000,
      ju: 0.25,
      jd: 0.5
    },
    throttledParameters: ExponentialBackoffWithJitterParameters {
      c: 5000,
      cMin: 10000,
      cMax: 60000,
      ju: 0.25,
      jd: 0.5
    }
  },
  _maxOperationTimeout: 240000,
  desiredPropertiesUpdatesEnabled: false,
  properties: {
    reported: { update: [Function: update], '$version': 1 },
    desired: { '$version': 1 }
  },
  [Symbol(kCapture)]: false
}

I don't want to listen the twin change events that I can do easily by using above object using twin.on. I need to just get the current twin of the device. Is it possible?

Answer 1

Above is not feasible to get the whole twin not just the desired and reported properties from device IoT sdk and that has been confirmed by Azure too. Check here.

The link also has a solution to assign parent child relationship between the leaf and the edge device.