Build and Deploy a Chat Application That Scales Horizontally with WebSockets and Upstash Redis

Ui repo link -> https://github.com/RitulBhatnagar/scalable-chat-app-ui/tree/master

What I have use?

1. Fastify - Backend
2. Websockets - Realtime
3. Next.js - Frontend
4. Tailwind & Shadcn UI - Styling
5. Redis - Pub/Sub
6. Docker/docker-compose - Containerization
7. GitHub actions - CI/CD
8. DigitalOcean - Host the backend
9. Vercel - Host the frontend

System architecture

Data flow

Debugging

Websockets

1. Using wss:// and not ws:// in production
2. Use debug mode in Caddy server

{
    debug
}

Docker

1. List our running docker containers

docker ps

1. Stop a running container

docker stop <container id>

1. Remove a container

docker rm <container id>

1. List out networks

docker network ls

1. Remove a network

docker network rm <network id>