Go for TUI on the web

Or "Backend is the new frontend". A story of a totally over-engineered personal website that uses a Go binary running in Docker container on a lightweight Kubernetes installation as a "frontend".

Transcript

1. Andrey “Andy” Baranov Go for TUI on the web Backend is the new frontend Story of a totally over-engineered
 personal website
2. GUI TUI
3. Disclaimer: I’m not a true gopher (but a rubyist impostor)
4. Andrey “Andy” Baranov • From Soviet Russia • Non-STEM background (TV journalism) • Lived in 5 countries • In Berlin since 2019 • SRE at Le Wagon 
 (Ruby, Rails, Kubernetes, code sandboxing) • Writer at Evil Martians https://evl.ms/blog github.com/progapandist twitter.com/progapandist
6. is hard • Building complex interactions requires a whole stack, separate from backend • “Full-stack” is a • Standards galore • Browser wars • Have you tried to build a form recently? Modern frontend
7. • One programming language • Single binary • Reusable “widgets” • ANSI standard 
 (ECMA-48/ISO/IEC 6429) 
 haven’t changed since 1991 • Ever heard of TTY wars? Remember this?
8. Can I have it… in a browser?
9. Challenge • No CSS/HTML/JS for UI components • TTY in browser • Web app == terminal app Retro-futurism
10. My frontend skills are rusty… So let’s just bring the full terminal to the frontend • Xterm.js — powers Terminal in VS Code, 
 Hyper, etc… Full support for ANSI • Svelte.js because I wanted to try out smth new • Parcel.js to bundle with zero config • 100 lines of full “frontend” code in one file,
 mostly to handle WebSocket connections • WebSocket messages are our STDIN/STDOUT • Send every keystroke as a binary message
12. What about the backend?
13. WebSocketing and PTYing • gorilla/websocket (no-brainer choice) • creack/pty (a Go package for using unix pseudo-terminals) Enter Golang
14. as a secret sauce • Cool, so I can PTY and the hell out of a server. Or mine my crypto! • Not unless we can control the environment you PTY into • Alpine Linux! • No network • Limit resources Docker
15. Run it!
16. entrypoint.sh inside user container
17. Implementing TUI “frontend”
18. Gophers love devtools, right? And developers love terminals!
19. Go TUI libs
20. Inspiration: derailed/k9s
21. And the winners are… • German engineering! • Amazing API • Lots of widgets • Oliver, if you see this — I’ll buy you a !
22. https://bit.ly/38vVnZk
23. Deployment • DO $10 droplet • k3sup for a single-machine k8s
 with Traefik ingress • docker:stable-dind for sidecar
 (to run user sandbox) • 1 Go binary for HTTPS/WSS server • 1 Go binary for TUI app • 2 Docker images • Survived Reddit
24. Thank you! https://github.com/progapandist/progapanda.org/