fix(metrics): use ServeMux route pattern as label, not raw URL - #57
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samcm wants to merge 4 commits into
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fix(metrics): use ServeMux route pattern as label, not raw URL#57samcm wants to merge 4 commits into
samcm wants to merge 4 commits into
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The Metrics middleware was labeling http_requests_total, http_request_duration_seconds, http_request_size_bytes, and http_response_size_bytes with r.URL.Path. Every unique URL — including vulnerability-scanner probes (/.env, /wp-login.php) and per-network proxy paths (/api/v1/<network>/...) — became a permanent metric series in indexdb. Production VictoriaMetrics observed ~48k distinct path values from this app alone. Use r.Pattern (set by net/http.ServeMux after routing) instead, with an "unmatched" sentinel as a defensive fallback. The path label name is preserved for dashboard compatibility but its values are now bounded by the number of registered routes.
mattevans
approved these changes
May 13, 2026
The workflow used 'version: latest' which broke CI when a newer golangci-lint release tightened goconst/wsl rules and started flagging pre-existing strings across the repo. v2.11.4 is the version that ran on the last green master build (#55, 2026-04-24).
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The Metrics middleware labels
http_requests_total,http_request_duration_seconds,http_request_size_bytes, andhttp_response_size_byteswithr.URL.Path— so every unique URL (vuln-scanner probes like/.env,/wp-login.php, and per-network proxy paths) becomes a permanent series in the metrics store. Production VictoriaMetrics observed ~48k distinctpathlabel values from this app alone.This switches the label to
r.Pattern(set bynet/http.ServeMuxafter routing) with anunmatchedsentinel as a defensive fallback; the label name stayspathfor dashboard compatibility but values are now bounded by the registered route count.