Azure IoT Hub

Use this node to publish messages to Azure IoT Hub via MQTT — for example, forwarding device telemetry collected in ThingsBoard to an Azure IoT Hub for processing by Azure Stream Analytics, or sending device-to-cloud messages to trigger Azure Functions.

Configuration

Topic pattern — MQTT topic. Default: devices/{clientId}/messages/events/. Supports templatization.
Host — Azure IoT Hub hostname: {iot-hub-name}.azure-devices.net.
Client ID — the device ID as registered in Azure IoT Hub.

Credentials

Type	Required fields
SAS Token	`sasKey` (primary or secondary key); optional `caCert`
PEM Certificate	Client `cert` + `privateKey`; optional `caCert` and key `password`

MQTT retransmission

Exponential backoff with jitter for unacknowledged QoS 1 messages:

Variable	Default
`TB_MQTT_CLIENT_RETRANSMISSION_MAX_ATTEMPTS`	`3`
`TB_MQTT_CLIENT_RETRANSMISSION_INITIAL_DELAY_MILLIS`	`5000`
`TB_MQTT_CLIENT_RETRANSMISSION_JITTER_FACTOR`	`0.15`

Message processing algorithm

Resolve the topic pattern from message data and metadata.
Publish the message data to IoT Hub via MQTT with QoS 1.
On acknowledgment: route via Success.
On error: add error to metadata; route via Failure.

Output connections

Connection	Condition
`Success`	Message published and acknowledged by IoT Hub.
`Failure`	Authentication failure, retransmission exhausted, or unexpected error. Error details in metadata `error` key.

Examples

Example 1 — Forward telemetry to IoT Hub

Data: { "temperature": 22.5, "humidity": 65 }.

{
  "topicPattern": "devices/sensor-001/messages/events/",
  "host": "my-hub.azure-devices.net",
  "clientId": "sensor-001",
  "credentials": {
    "type": "sas",
    "sasKey": "base64encodedKey=="
  }
}

Result: message published to IoT Hub. Routes via Success.

JSON schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "TbAzureIotHubNodeConfiguration",
  "type": "object",
  "required": ["topicPattern", "host", "clientId", "credentials"],
  "additionalProperties": false,
  "properties": {
    "topicPattern": { "type": "string" },
    "host": { "type": "string" },
    "clientId": { "type": "string" },
    "connectTimeoutSec": { "type": "integer" },
    "credentials": { "type": "object" }
  }
}