How to Use WebSockets with Redis Pub/Sub for Scaling

You scale WebSockets with Redis Pub/Sub by having each server instance subscribe to a shared Redis channel and broadcast messages to it when a client connects or sends data. This ensures all connected clients across all servers receive the same real-time updates.

// Server A: Publish message to Redis
redisClient.Publish(ctx, "chat-room", message)

// Server B: Subscribe to Redis channel
sub := redisClient.Subscribe(ctx, "chat-room")
for {
    msg, _ := sub.Receive(ctx)
    // Broadcast msg to local WebSocket connections
}

Using WebSockets with Redis Pub/Sub lets multiple server computers talk to each other instantly using Redis as a messenger. When a user sends a message to one server, that server tells Redis, and Redis whispers the message to all other servers so they can show it to their users. It's like a group chat where Redis is the person repeating what everyone says to the whole room.