Frontend code for subscribing to and receiving push notifications in the browser

Demo project for c't Magazin in April 2018

This shows several phases of building an own web push client.

• Phase 1: show notifications
• Phase 2: register a service worker
• Phase 3: send messages from dev tools
• Phase 4: send messages from Push companion
• Phase 5: build your own subscription service based on PHP/MySQL and send messages from the command shell using web-push. The included bash script creates a key pair and requires a shell with OpenSSL, dd, and tr (can be installed in Windows with Cygwin)
• Phase 6: create a more elegant solution (not included)