This is a basic integration of Electron and Chrome Web-Bluetooth API, Specifically, implementing 1) device info sample provided by the api, 2) getting values from a bluetooth device, and 3) setting a value to a bluetooth device.
# Go into the repository
cd electron-web-bluetooth
# Install dependencies
npm install
# Run the app
npm start
To get heart rate data, I've used a Bluetooth Prephiral Simulator app called LightBlue downloaded from the App Store. There, create a virtual prephiral service for heart rate. Go to the 'Heart Rate Control Point' characterisitc, add read and write capabilities. You can also set a default Hex value. You need this to be able to get a result from 'Get Heart Rate' button.