README §3 promised a monitoring story ("aggregate into Prometheus via
a sidecar that polls the data model"). Nothing shipped. Customers
running a real fab without a metrics pipeline find out about T7
storms, spool blowups, and stalled CJs after their MES does — not
the position you want SRE in.
This commit ships:
- include/secsgem/metrics/prometheus.hpp: header-only. A Registry
(counters + gauges + HELP/TYPE descriptions, label-keyed,
mutex-guarded so updates from the io thread and scrape renders from
the same io serialize cleanly) plus a PrometheusServer (asio
acceptor, replies to any GET with the text-exposition rendering,
no auth — drop nginx in front for that).
- tests/test_metrics_prometheus.cpp: 3 cases / 19 assertions.
Render counter+gauge with labels, scrape via raw TCP and parse the
HTTP body, verify live updates land on subsequent scrapes.
- INTEGRATION.md §6.4: worked example that pairs the exporter with the
Connection + EquipmentDataModel hooks documented in §6.1/§6.2.
Shows the wrap-around-handler trick for message counters, a 5s
polling timer for gauges (spool depth, active alarms), and the
expected /metrics output.
Deliberately *not* shipped:
- A StandardMetrics helper that auto-wires everything — would force
a single hook owner per store, breaking customers who want
composable observers. Customers wire what they need; the registry
gives them counters + gauges + an HTTP endpoint, no policy.
- TLS / auth on the HTTP endpoint. Reverse-proxy territory.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
raphael
6c6dc84c22