Build scalable WebSocket servers for real-time bidirectional communication. Use when enabling real-time bidirectional communication. Trigger with phrases like "build WebSocket server", "add real-time API", or "implement WebSocket".
npxskills add jeremylongshore/claude-code-plugins-plus-skills--skill building-websocket-serverLoading…
Build scalable WebSocket servers for real-time bidirectional communication using the ws library, Socket.IO, or native framework WebSocket support. Handle connection lifecycle management, room/channel subscriptions, message broadcasting, heartbeat keepalive, and horizontal scaling with Redis pub/sub adapters.
ws or socket.io, or Python 3.10+ with websockets or FastAPI WebSocket, or Go with gorilla/websocketUpgrade header forwarding)/ws, /socket.io) and allowed origins.upgrade event, rejecting unauthorized connections before protocol switch.type, channel, payload, and correlationId fields for structured bidirectional communication.See ${CLAUDE_SKILL_DIR}/references/implementation.md for the full implementation guide.
${CLAUDE_SKILL_DIR}/src/ws/server.js - WebSocket server setup and upgrade handling${CLAUDE_SKILL_DIR}/src/ws/handlers/ - Per-message-type handler functions${CLAUDE_SKILL_DIR}/src/ws/rooms.js - Room/channel subscription management${CLAUDE_SKILL_DIR}/src/ws/registry.js - Active connection tracking registry${CLAUDE_SKILL_DIR}/src/ws/heartbeat.js - Ping/pong keepalive logic${CLAUDE_SKILL_DIR}/src/ws/adapters/redis.js - Redis pub/sub adapter for scaling${CLAUDE_SKILL_DIR}/tests/ws/ - WebSocket connection and messaging tests| Error | Cause | Solution |
|---|---|---|
| 401 during upgrade | JWT token missing or expired in handshake query/headers | Reject upgrade with HTTP 401 before WebSocket protocol switch completes |
| 1008 Policy Violation | Client sends malformed message or violates protocol | Send close frame with code 1008 and human-readable reason; log violation |
| 1006 Abnormal Closure | Network interruption without close handshake | Detect via heartbeat timeout; clean up connection registry; notify room members |
| Memory leak | Connection registry grows unbounded from stale entries | Implement heartbeat-based cleanup sweep every 60s; enforce max connections per server |
| Message storm | Single client flooding messages beyond acceptable rate | Apply per-connection message rate limiting; disconnect abusive clients with 1008 |
Refer to ${CLAUDE_SKILL_DIR}/references/errors.md for comprehensive error patterns.
Chat application: Multi-room chat server where clients join named rooms, receive member presence updates, and see real-time message delivery with typing indicators via separate message types.
Live dashboard: Server pushes metric updates to subscribed dashboard clients every second, with initial state snapshot on connection and incremental deltas thereafter.
Collaborative editing: Operational transformation relay server that receives edit operations from clients, transforms against concurrent operations, and broadcasts resolved changes to all document subscribers.
See ${CLAUDE_SKILL_DIR}/references/examples.md for additional examples.
ws library: https://github.com/websockets/ws
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).