* Separate artifact and metadata cache metrics on /metrics and the analytics page
* Serve metadata cache stats from a shared snapshot and split Grafana cache panels by kind
The history is process-wide, and tests cleared it only after running, and
not all of them. Records from earlier tests or an earlier -count repetition
reached later assertions: TestRecordUpstreamOperations left a record for
TestRecentFailuresNewestFirst, and the server tests never cleared it.
- Export ResetRecentFailures so tests outside the metrics package can use it
- Clear the history before and after every test that records or reads
failures directly, in metrics, server and handler
- Assert exactly one failure in the handler tests instead of looking only
at the newest
- Failure recorders take a FailureDetail: PURL, filename, URL, storage path, error
- Keep the last 20 failures per counter series in memory, reset on restart
- Strip userinfo, query and fragment from URLs, including those inside error text
- Pass the detail from upstream, storage, integrity, health probe and scan call sites
- Package names and URLs stay out of Prometheus labels
- Ring of download size by ecosystem, cache figures, per-ecosystem
table, vulnerability overview and a Runtime card
- Add metrics.Gather so the page can render counters that were never
in the database
- Add proxy_response_bytes_total and response-writer byte counting
- Serve a retained snapshot behind a staleness banner when the
aggregation fails, rather than rendering old figures as current
- Extract the security overview into a shared component
Part 3 of 6 splitting #381 up.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
