Microsoft Azure IoT platform (3): visualizing real-time sensor data with Azure Web Apps

VISUALIZING REAL-TIME SENSOR DATA WITH AZURE WEB APPS

- Layout for this exercise:





* This exercise is based in the previous one


1 - Creating the Web App

- The goal of this exercise is to visualize real-time sensor data received by an IoT hub by running a web application that is hosted on a Web App. 

- Starting from the Azure portal, clicking New -> Web + Mobile -> Web App:









- Filling the required data, like App name, Resource Group, etc .. and pinning to the Dashboard:






- The Web App starts the deployment process:




- An URL is generated that later will be used to visualize real-time sensor data:








2 - Adding a consumer group to the IoT hub

- Consumer groups are used by applications to pull data from an Azure IoT Hub.

- Going back to the Azure portal and opening the IoT Hub:




- Clicking Endpoints -> Events:





- Entering a Consumer group name and saving:








3 - Configuring the Web App to read data from an IoT hub

- Opening the Web App:




- Clicking Settings -> Application settings:





- Entering two key/value pairs. The first one corresponds to the Connection String obtained in previous exercises, the second one refers to the Consumer group name:




- Saving:





- Enabling Web sockets:



- Going to Deployment option -> Choose Source -> Local Git Repository:








- Setting up authentication with username + password:




- The Web App is eventually successfully deployed:




- From Overview, let's copy the Git clone URL that will be used later:




4 - Uploading a web application to be hosted by the Web App

- Now, let's go to the Raspberry Pi device and open a terminal window.

- Entering these commands using:

a) Git clone URL from the previous point
b) appropriate authentication credentials (username + passwords) from the previous point














- Running the simulated Temperature/Humidity sensor device:




- Browsing the URL generated before:




- Finally, the Temperature/Humidity real-time data generated by the simulated device is visualized:

Microsoft Azure IoT platform (2): connecting a simulated device to an IoT Hub using Node.js

MICROSOFT AZURE (2): CONNECTING A SIMULATED DEVICE TO AN IoT HUB USING NODE.JS





* This exercise is based on the previous one


1 - Creating a device identity

- CreateDeviceIdentity.js creates a device identity and associated security key to connect a simulated device app.

- Running this console app generates a unique device ID and key that the device can use to identify itself when it sends device-to-cloud messages to IoT Hub.

- New folder:




- Checking that node and npm are correctly installed:




- npm creates a json package, just accepting the default options:




- Installing the azure-iothub service SDK package:




- Writing the CreateDeviceIdentity.js file:






- It is important to notice that the variable connection string holds the "connection string - primary key" obtained in the previous exercise:








- Also, the deviceID must be entered:






- Running the program, a new Device key is generated:





- The Device key is written down or copied and added to the document with all the parameters and keys:




2 - Receive device to cloud messages

- ReadDeviceToCloudMessages.js displays the telemetry sent by the simulated device app, reading device-to-cloud messages from IoT Hub using the AMQP protocol.

- New folder:




- Creating a new json package file and accepting all the default options:



- Installing azure-event-hubs package and saving it:




- Writing the program ReadDeviceToCloudMessages.js:





- As before, it is important to notice that the connection string key must be introduced in the variable connectionString.


3 - Simulated Device

- SimulatedDevice.js connects the IoT hub with the device identity created earlier, and sends a telemetry message every second using the MQTT protocol.

- New folder:




- json package:




- Installing azure-iot-device and azure-iot-device-mqtt:




- Writing the program, and using the connectionString variable with the Device key value originated at the section Create a device identity (point 1 of this exercise):






- All of these parameters must be carefully entered:










4 - Running the application

- To run the two applications a separate console must be used, so that the communication between the simulated device and the IoT hub can be displayed.

- Running SimulatedDevice.js to send telemetry data to the IoT hub:





- Running ReadDeviceToCloudMessages.js to monitor the IoT hub: