LibreChat/api/server
Danny Avila 2d794a0439
💓 fix: Detect Silently Dead Redis Sockets With Deadline-Bounded Heartbeats (#15539)
* fix: Detect silently dead Redis sockets with deadline-bounded heartbeats

A Redis peer can vanish without a FIN or RST (a dropped NAT entry, a proxy
failover, a migrated VM). The socket stays `ready` from ioredis's point of
view, no error fires, and every command on it waits for the kernel's
retransmission timeout — about fifteen minutes at Linux defaults.

Observed in production: while the main client's socket was dead,
POST /api/agents hung until Cloudflare returned a 524; while the subscriber's
socket was dead, every attach failed with "Timed out synchronizing Redis
subscription" for sixteen minutes across five conversations.

`REDIS_PING_INTERVAL` could not help — it awaits ping() with no deadline, so
the probe just joins everything else that is waiting.

- Add startRedisHeartbeat: races a PING against a deadline and destroys the
  socket when the probe goes unanswered, so ioredis reconnects, replays queued
  commands, and re-subscribes a subscriber's channels.
- Destroy the stream rather than disconnect(true), whose FIN a vanished peer
  never acknowledges; cluster clients fall back to the regular reconnect.
- Add createIoRedisSubscriber so every dedicated subscriber gets an error
  listener and its own heartbeat, and route the generation-stream and both
  subagent-routing subscribers through it.
- Set ioredis keepAlive from REDIS_KEEP_ALIVE (default 10s).
- Add REDIS_PING_TIMEOUT, REDIS_SUBSCRIBER_PING_INTERVAL and REDIS_KEEP_ALIVE,
  documented in .env.example.
- Give the fake RESP server a silent mode and a SUBSCRIBE reply so the
  dead-peer case can be tested against real clients.

* fix: Probe each cluster node and refuse a non-positive heartbeat deadline

A cluster-level PING is routed to one node, so a healthy reply proved nothing
about the other sockets. The heartbeat now resolves its targets each tick —
every node for a cluster, the client itself otherwise — and races an
independent deadline per target, tearing down only the socket that stops
answering. A non-positive deadline disables the heartbeat with a warning
instead of forcing a reconnect on every tick, and the single-probe test no
longer depends on wall-clock slack.
2026-09-03 09:45:16 -04:00
..
controllers 🧊 feat: Persist Context Fading Tier Across Agent Runs (#15505) 2026-09-02 20:29:43 -04:00
middleware 🧊 feat: Persist Context Fading Tier Across Agent Runs (#15505) 2026-09-02 20:29:43 -04:00
routes 🧊 feat: Persist Context Fading Tier Across Agent Runs (#15505) 2026-09-02 20:29:43 -04:00
services 💓 fix: Detect Silently Dead Redis Sockets With Deadline-Bounded Heartbeats (#15539) 2026-09-03 09:45:16 -04:00
utils 🧊 feat: Persist Context Fading Tier Across Agent Runs (#15505) 2026-09-02 20:29:43 -04:00
cleanup.js
csp.spec.js 🔣 fix: Escape SPA Language Attribute (#15248) 2026-08-26 07:37:36 -04:00
experimental.js 🚰 fix: Record the Provider Drain When Shutdown Cuts a Generation Short (#15532) 2026-09-03 07:11:38 -04:00
experimental.spec.js 🧾 feat: Store Durable Event Actor Receipts (#15265) 2026-08-27 06:00:43 -04:00
index.js 🚰 fix: Record the Provider Drain When Shutdown Cuts a Generation Short (#15532) 2026-09-03 07:11:38 -04:00
index.metrics.spec.js ⏱️ feat: Run Scheduled Chats Through Durable Agent Triggers (#14939) 2026-08-20 11:51:30 -04:00
index.spec.js 🦺 feat: Configurable Baseline HTTP Security Headers (#14445) 2026-08-25 08:21:39 -04:00
socialLogins.js
socialLogins.spec.js
telemetry.js
telemetry.spec.js