Commit Graph

2 Commits

Author SHA1 Message Date
unkin-agent c0aab83c20 Convert a single-flight panic into an error
ci/woodpecker/pr/build Pipeline was successful
ci/woodpecker/pr/test Pipeline was successful
ci/woodpecker/pr/pre-commit Pipeline was successful
- flightGroup.Do recovers a panicking fn so the leader and every waiter get a non-nil error instead of a zero-value success served as 200 []
- Note in the README that facts_cache_bytes budgets body bytes only
2026-09-05 21:03:23 +10:00
unkin-agent 1e2acc9c14 feat: cache merged /facts and /nodes in memory, stale on backend failure
A busy Puppetboard re-fans-out the same /facts query every few seconds, and a
502 is worse than 30-second-old facts when every PuppetDB is unreachable.

- Add a `Cache` interface (get reports fresh/stale/miss, put, stats) keyed on
  `<path>?<params>` with keys and repeated values sorted, plus a no-op default
  so uncached paths behave exactly as before.
- Route serveMerged/serveUnion/serveSummed through `serveCached`, so the
  reports cache drops in at `cacheFor` without touching a handler.
- Back /facts and /nodes with a byte-bounded LRU: `facts_ttl` (default 30s,
  clamped to a 30s cap) and `facts_cache_bytes` (default 64 MiB); expired
  entries are kept and served only when every backend fails.
- Single-flight identical keys so N concurrent requests cause one fan-out.
- Surface `cache` state and `serving_stale` in /healthz and the cache settings
  in `config show`.
2026-09-05 21:03:23 +10:00