Sending data to MS Azure IoT Hub

This example demonstrates the basic usage of the Gateway's Azure IoT Hub device output in order to show how to provide a bridge between Nerve and Microsoft's IoT infrastructure. The instructions below describe an easy-to-use way to send data from an MQTT demo sensor to an MS Azure IoT Hub device.

Note

An MS Azure IoT Hub device is required before attempting the following example. Refer to the official Microsoft Azure IoT Hub documentation in the section Create a hub using the Azure portal for more information.

Provisioning and deploying the sensor simulation and the MQTT broker

In the instructions below two Docker workloads will be provisioned and deployed:

An MQTT broker must to be deployed to the node first in order for the sensor simulation to function. The EMQX MQTT broker is used in this example that can be downloaded from the Docker Hub registry.

Afterwards the temperature and humidity sensors simulation MQTT publisher is deployed. Download the Data Services MQTT demo sensor found under Example Applications from the Nerve Software Center. This is the Docker image that is required for provisioning the demo sensor as a Docker workload.

Log in to the Management System. Make sure that the user has the permissions to access the Data Services.

Provision a Docker workload for the EMQX MQTT broker by following Provisioning a Docker workload. This example uses emqx-4.1.0 as the workload name. Use the following workload version settings:

Setting	Value
Name	Enter any name for the workload version.
Release name	Enter any release name.
DOCKER IMAGE	Select From registry and enter `emqx/emqx:v4.1.0`.
Container name	`emqx`
Network name	`host`

Provision a Docker workload for the sensor simulation by following Provisioning a Docker workload. Use the following workload version settings:

Setting	Value
Name	Enter any name for the workload version.
Release name	Enter any release name.
DOCKER IMAGE	Select Upload to add the Docker image of the sensor simulation that has been downloaded from the Nerve Software Center.
New environment variable	Select the + icon and enter the following information: Env. variable `MQTT_PUB_TOPIC` Variable value `demo-sensor-topic`
Container name	`ttt-mqtt-demo-sensor-1.0`
Network name	`host`

Deploy both provisioned Docker workloads above by following Deploying a workload.

Configuring the Data Services Gateway

The example demonstrates the simplest configuration for the Azure IoT Hub Device output and omits any parameters that are not required. Since the definition of a connector has been omitted, the Gateway will generate a default connector at index 0 with the following fields:

name: automatically generated name that is used in logs
timestampRequired: false

Follow the instructions below to apply the Gateway configuration.

Access the Local UI on the node. This is Nerve Device specific. Refer to the table below for device specific links to the Local UI. The initial login credentials to the Local UI can be found in the customer profile.

Nerve Device	Physical port	Local UI
MFN 100	P1	http://172.20.2.1:3333
Kontron KBox A-150-APL	LAN 1	`<wanip>:3333` To figure out the IP address of the WAN interface, refer to Finding out the IP address of the device in the Kontron KBox A-150-APL chapter of the device guide.
Kontron KBox A-250	ETH 2	`<wanip>:3333` To figure out the IP address of the WAN interface, refer to Finding out the IP address of the device in the Kontron KBox A-250 chapter of the device guide.
Maxtang AXWL10	LAN1	`<wanip>:3333` To figure out the IP address of the WAN interface, refer to Finding out the IP address of the device in the Maxtang AXWL10 chapter of the device guide.
Siemens SIMATIC IPC127E	X1 P1	http://172.20.2.1:3333
Siemens SIMATIC IPC427E	X1 P1	http://172.20.2.1:3333
Supermicro SuperServer E100-9AP-IA	LAN1	`<wanip>:3333` To figure out the IP address of the WAN interface, refer to Finding out the IP address of the device in the Supermicro SuperServer E100-9AP-IA chapter of the device guide.
Toshiba FA2100T-700	First rear port	http://172.20.2.1:3333
Vecow SPC-5600-i5-8500	LAN 1	http://172.20.2.1:3333
Winmate EACIL20	LAN1	`<wanip>:3333` To figure out the IP address of the WAN interface, refer to Finding out the IP address of the device in the Winmate EACIL20 chapter of the device guide.

Select the arrow next to Data to expand the Data Services sub menus in the navigation on the left.
Select Gateway.
Select the Edit configuration icon on the right to enter editing mode.

Create a JSON file out of the following Gateway configuration:

{
    "inputs": [
        {
            "type": "MQTT_SUBSCRIBER",
            "clientId": "mqtt_subscriber_0",
            "serverUrl": "tcp://localhost:1883",
            "keepAliveInterval_s": 20,
            "cleanSession": true,
            "qos": 1,
            "connectors": [
                {
                    "topic": "demo-sensor-topic",
                    "variables": [
                        {
                            "name": "temperature",
                            "type": "int16"
                        },
                        {
                            "name": "humidity",
                            "type": "uint16"
                        }
                    ]
                }
            ]
        }
    ],
    "outputs": [
        {
            "type": "AZURE_IOT_HUB_DEVICE",
            "deviceConnectionString": "HostName=<YOUR_IOT_HUB_HOSTNAME>;DeviceId=<YOUR_DEVICE_ID>;SharedAccessKey=<YOUR_DEVICE_SAK>"
        }
    ],
    "connections" : [
        {
            "input": { "index" : 0, "connector" : 0 },
            "output": { "index" : 0, "connector" : 0 }
        }
    ]
}

Note

Replace the value of deviceConnectionString in the configuration above with the connection string of the device that was created before in the MS Azure IoT Hub. Make sure to copy the string that is marked as PRIMARY. Refer to Register a new device in the IoT hub in the official Microsoft Azure IoT Hub documentation for more information.

Select the Import button.
Add the JSON configuration file containing the code above from the file browser.
Select the Deploy button. A success message pops up in the upper-right corner.

The configuration is now deployed. The graphical configuration tool now reflects the contents of the JSON file. Exit editing mode by selecting the arrow on the left. Details of each input and output can be opened by selecting the magnifying glass symbol next to each input and output.

Select the Logs tab to view the Gateway logs for more information.

Verifying the data transmission

The official Microsoft Azure IoT Hub documentation describes multiple ways of verifying if data is being sent from the Nerve node to the Azure IoT Hub device. This example uses a python script utilizing the built-in event hub that is available by default for every created Azure IoT Hub device. This method is valid for every type of Azure subscription, including the free or basic tier. The script is taken from the official Azure sample repository on GitHub. To get it, clone the repository by opening the terminal and running the following command. This requires Git to be installed on the workstation:

git clone https://github.com/Azure-Samples/azure-iot-samples-python

If Git is not installed, visit the repository page and select Code > Download ZIP to download the repository as a ZIP file.

Note

Python version 3.7.0 or higher is required to successfully run the example.

Navigate to iot-hub/Quickstarts/read-d2c-messages/ inside the cloned repository.
Open the Readme.md file.
Read the instructions carefully.
Choose either the read_device_to_cloud_messages_async.py or read_device_to_cloud_messages_sync.py. This example works with both scripts.
Replace the placeholder variables below in the chosen script with information from the Event Hub-compatible connection string. This string is obtained when the Azure IoT Hub device is created.

EVENTHUB_COMPATIBLE_ENDPOINT

EVENTHUB_COMPATIBLE_PATH

IOTHUB_SAS_KEY
Enter the following command to install the azure-eventhub package:
```
pip install azure-eventhub
```
Run the script that was chosen earlier with one of the following commands or executing the file:
```
python read_device_to_cloud_messages_async.py
```
or
```
python read_device_to_cloud_messages_sync.py
```

The result of the script will look similar to the screenshot below:


`EVENTHUB_COMPATIBLE_ENDPOINT`
`EVENTHUB_COMPATIBLE_PATH`
`IOTHUB_SAS_KEY`