Azure Iot Hub Transmit

An azure iot hub transmit (connects to an Azure IoT Hub instance). This client should be used in non-nested instances, or when direct IoTHub routing is required.

Example:

If we want to upload our records from the bathhouse:water stream to our IOT cloud, going through an IoT (non-edge) HuB endpoint, the config will look like this:

{
    "data_transmit": [
        {
            "transmit_name": "iot_hub_transmit",
            "transmit_type" : "iothub",
            "filter_stream": [
                "bathhouse:water"
            ],
            "connection_string": "HostName=...;SharedAccessKeyName=...;SharedAccessKey=..."
        }
    ]
}

Configuration:

Required and optional properties that can be configured for the transmit.

• connection_string: A string that provides all the connection info. (Can be found in “Devices” -> “<Actual Device Name>” -> “Primary connection string” in the relevant iot hub page)
• additional_fields: additional field to add in the message payload for e.g. { “processingPath”: “SM”}
• use_websockets: Option to connect to MQTT over websockets (Defaults to False)
• transmit_name: ID for the transmit. It must be unique.
• transmit_type: Method to use in transmitting records.
• filter_stream: A list of streams that will use the transmit. Each stream can either be * (all) or asset:stream.
• timeout: Number of seconds to wait until timing out.
• poll_interval: Maximum number of seconds to wait between requests
• max_request_records: Maximum number of records to send in a single request.
• max_request_size_bytes: Maximum number of bytes allowed in a single request. Size is capped at 4 MB.
• opc_payload_metadata: Additional fields to add in the OPC-formatted payload. E.g. { “TiqTwin”: { “NodeId”: “a2ec725a-78e2-431b-a124-ce20b8e3e4c6” }} Ignored if use_opc_publisher_format is False.
• opc_message_metadata: Per-message metadata fields to add in the OPC-formatted payload.
• use_opc_publisher_format: If True, the message payload will be formatted to mimic OPC Publisher. https://github.com/Azure/Industrial-IoT/tree/main/docs/opc-publisher#opc-publisher-telemetry-formats