websocket-relay/.agents/summary/review_notes.md

Documentation Review Notes

Consistency Check Results

✅ Consistent

• Configuration documented in data_models.md matches actual config.go struct
• Hub methods documented in components.md match actual implementation
• CLI flags documented in interfaces.md match main.go
• Build commands in codebase_info.md match Makefile

⚠️ Inconsistencies Found

Issue	Location	Details
Port mismatch in example client	example/index.html	Uses ws://localhost:8000/ but config default is port 8443
Metrics type mismatch	internal/metrics/metrics.go	MessagesTotal, ConnectionsTotal, DisconnectionsTotal are defined as Gauge but semantically represent counters (monotonically increasing values). Should be Counter type.
Silent client removal	internal/hub/hub.go	During broadcast, write errors cause client removal without going through the unregister channel, meaning DisconnectionsTotal and ConnectedClients metrics won't be updated correctly.
README port reference	README.md	Mentions TLS is enabled by default, but config.yaml has tls.enabled: false

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Completeness Check Results

✅ Well-Documented Areas

• Core WebSocket relay logic
• Configuration structure and loading
• Build and deployment pipeline
• Metrics definitions

❌ Documentation Gaps

Gap	Severity	Recommendation
No graceful shutdown	Medium	Document that the server lacks graceful shutdown — connections are terminated abruptly on SIGTERM
No rate limiting	Medium	Document absence of rate limiting and implications for production use
No message size limits	Medium	No ReadLimit set on WebSocket connections — potential DoS vector
No health check endpoint	Low	No /health or /ready endpoint for orchestrators
No connection limits	Medium	No max client count — server could be overwhelmed
No logging configuration	Low	Uses default log package with no level control
No deployment docs	Medium	No systemd unit file, Docker instructions, or k8s manifests
Missing test coverage	Medium	internal/metrics has no tests; hub integration tests (actual WebSocket connections) missing

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Language Support

Aspect	Support Level	Notes
Go source analysis	✅ Full	All Go code fully analyzed
HTML/JS (example)	✅ Full	Simple single-file client analyzed
YAML configs	✅ Full	Configuration fully documented
Makefile	✅ Full	All targets documented
Gitea Actions YAML	✅ Full	CI/CD pipelines documented

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Recommendations

High Priority

1. Fix metrics types: Change MessagesTotal, ConnectionsTotal, DisconnectionsTotal from Gauge to Counter
2. Fix broadcast disconnect handling: Route write-error disconnections through the unregister channel to maintain accurate metrics
3. Add message size limits: Set conn.SetReadLimit() to prevent memory exhaustion

Medium Priority

4. Add graceful shutdown: Use context.Context and http.Server.Shutdown()
5. Add health endpoint: Simple /health returning 200 OK
6. Add integration tests: Test actual WebSocket connections end-to-end
7. Fix example port: Update example/index.html to use port 8443

Low Priority

8. Add structured logging: Replace log with slog or zerolog
9. Add connection limits: Max concurrent connections configuration
10. Add Docker support: Dockerfile and docker-compose for easy deployment