Handling Edge Cases
1. Handling Simultaneous Connections
Case Strategy Multi-tab Allow N; share via BroadcastChannel Same device repeat connect Replace older or limit N Concurrent login Close oldest session
2. Handling Connection Migration
Trigger Detail Network switch (Wi-Fi → cell) Reconnect with resume token IP change Re-handshake VPN connect Force close + reconnect
3. Handling Server Restart
Server Restart Sequence
Server SIGTERM → stop accepting
Broadcast close 1001 with retry hint
Drain in-flight messages (timeout)
Exit process; new version starts
Clients reconnect with jitter
4. Handling Clock Skew
Mitigation Detail Server timestamps Authoritative time on messages Skew estimate (serverTs - clientTs) averageJWT leeway ±30s on exp/nbf NTP sync Server clocks via chrony/ntpd
5. Handling Message Reordering
Source Mitigation Single socket TCP guarantees order Reconnect Sequence number + buffer Pub/sub fan-out Order per topic; not cross-topic
6. Handling Partial Messages
Note: Browsers always deliver complete WebSocket messages (reassembled from fragments). Application-level partial messages must be modeled explicitly with chunk IDs.
Layer Behavior Protocol fragmentation Auto-reassembled App chunking Reassemble by id/seq Streaming API (WebSocketStream) True streaming chunks
7. Handling Unicode Characters
Issue Detail Surrogate pairs Use String.prototype[Symbol.iterator] for char count Normalization str.normalize("NFC")Byte length new TextEncoder().encode(str).lengthBad UTF-8 Server closes 1007
8. Handling Empty Messages
Frame Treatment Empty text Valid; e.data === "" Empty binary Valid; zero-length buffer App schema Reject if required field absent
9. Handling Connection Limits
Layer Limit Browser per-origin Typically 200+ (no strict cap) OS file descriptors ulimit -n (raise to 65535+)Ephemeral ports ~28k per src IP LB Per-target / per-listener caps
10. Handling Memory Leaks
Common Leak Fix Closure captures buffer Null reference on close Pending RPC map Reject on close + clear Listener accumulation AbortController Subscriber registry Cleanup on disconnect