In this lab assignment we'll explore hot to leverage online databases to write and read sensor data from an IoT application and access this data from anywhere in the world. We'll use two similar DB platforms: InfluxDB and Firebase.

Firebase is Google’s set of hosting services for mobile applications, which comprises a wide range of solutions to manage data from Android, iOS or web applications. We will use the real-time database solution from Firebase (RTDB) and we will store and read values from the DB using our ESP32 boards.

We can send and receive data with the ESP32 board to/from Firebase from anywhere in the world, as long as we have an Internet connection. This, coupled with the fact that we can create a web app that can be accessed anywhere with an Internet connection makes Firebase a very powerful tool, as you can manage, monitor, automate and send commands to an IoT application remotely.

First step is to create a Firebase project with a real-time database and use the ESP32 to write and read data from this database.

• Sign in to Firebase with your Google account
• Click Get Started, and then Create Project to create a new project
• Give a name to your project, for example: ESP32 Firebase
• Click to Disable Google Analytics (we don't need it for this simple demo)

If everything went well, you should be able to see your project page displayed in a few seconds.

We need to set an authentication method for our app.

In the left sidebar, click on Build → Authentication → Get Started

There are several authentication methods from different sign-in providers. For the purpose of this app where the ESP32 board connects directly to the Firebase app, we can select to have no authentication. Select Anonymous from the list, click to enable and the Save.