iot-store-display hosts the Firebase aspects of an IoT project relying on GCP-Cloud IoT Core. We called our GCP project hello-cloud-iot-core.

Devices publish weather data messages to a telemetry topic connected to the MQTT bridge of Cloud Iot Core.

A device is an ESP32 Wifi chip associated with a DHT22 temperature/humidity sensor. The ESP32 runs Mongoose OS.

All data messages are then forwarded to a Cloud Pub/Sub topic of the project and this is where the files in this repository intervene:

• A Cloud Function for Firebase is triggered upon a publication to the Cloud Pub/Sub topic. Its aim is to log the last weather data as it is published and also to store it in a Firebase Realtime Database. The Cloud Function implementation is the index.js file, hosted in the functions directory.
• The read/write rules of this database are described in the database.rules.json file.
• A web app hosted by Firebase Hosting is in charge of plotting the n last weather data each time a new data arrives in the Realtime Database. The files for this web app are hosted in the public directory.

Cloud IoT Core architecture, devices firmware & provision and Cloud Function & web app setups are all extensively described in this Medium post.

A live demo corresponding to the web app presented in this repository is avalaible here. There are two devices, one "indoor" and one "outdoor". Each one makes a measure every two minutes. The last 750 measures are plotted for each device, corresponding to approximately 24 hours.