fix(prometheus): serve scrapes from cached background poll (#1013)

mirror of https://github.com/unpoller/unpoller.git synced 2026-10-18 22:40:03 +02:00

Decouples Prometheus scrape cadence from upstream UniFi API calls so a
429 backoff loop on the controller side no longer stalls /metrics. The
output plugin now owns a 60s background poller (configurable) whose
result is served from an in-memory cache. Concurrent /scrape requests
for the same target are coalesced via singleflight to prevent a noisy
scraper from multiplying upstream load.

Adds two new metrics so operators can detect cache staleness and
refresh failures independently:
- unpoller_prometheus_cache_age_seconds
- unpoller_prometheus_refresh_failures_total

Background goroutine recovers from panics so a malformed input payload
no longer silently kills refreshes.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

This commit is contained in:

Cody Lee

2026-05-11 17:43:44 -05:00

co-authored by

Claude Opus 4.7

parent 0b83c6ad19

commit dabfeffe66

8 changed files with 635 additions and 4 deletions

examples/up.json.example

+2 -1

View File

@@ -11,7 +11,8 @@
     "http_listen":   "0.0.0.0:9130",
     "ssl_cert_path": "",
     "ssl_key_path":  "",
     "report_errors": false
     "report_errors": false,
     "interval":      "60s"
   },
   "influxdb": {