Production hardening II Phase 8 — surface the OCSP per-event counters
shipped in Phase 1+2 through the existing /api/v1/metrics/prometheus
endpoint. Operators now alert on certctl_ocsp_counter_total
{label="rate_limited"} (Phase 3 trip), {label="nonce_malformed"}
(Phase 1 reject), {label="signing_failed"} (issuer connector fails),
etc.
NEW interface CounterSnapshotter (handler/metrics.go) — minimum
surface the Prometheus exposer needs from any per-area counter table:
just Snapshot() map[string]uint64. service.OCSPCounters.Snapshot
(Phase 1) satisfies it; future per-area counters (CRL, cert-export,
EST per-profile, SCEP per-profile, Intune per-profile) plug in the
same way as separate SetXxxCounters setters.
Naming convention per frozen decision 0.10:
certctl_<area>_counter_total{label="<event>"} <value>
This commit ships only the OCSP block. The remaining areas (CRL,
cert-export, EST, SCEP, Intune) plug in via the same
SetXxxCounters pattern in follow-up commits — the wire-up cost per
area is one new field + one setter + one block of fmt.Fprintf lines.
The bundle's S-1 docs-count guard means we don't claim a specific
total in prose; operators run `curl /api/v1/metrics/prometheus | grep
certctl_` to enumerate.
Wired in cmd/server/main.go: a single shared *service.OCSPCounters
instance is created once and passed to BOTH the
ocspResponseCacheService (so the cache hot path ticks counters) AND
metricsHandler.SetOCSPCounters (so the Prometheus exposer reads
them). Existing dashboard metrics (certctl_certificate_total,
certctl_agent_total, etc.) remain unchanged at the same line offsets
— back-compat preserved.
Pre-commit verification: go build ./... clean; go test -short
-count=1 green for handler/ + service/. The existing
TestGetPrometheusMetrics_Success tests still pass (the new counter
block is additive at the END of the response body, after the
existing dashboard metrics + uptime line).
Critical alerts can no longer be silently dropped by a transient
notifier failure. Failed notification attempts now ride an exponential
backoff retry loop, with a 5-attempt budget before promotion to the
dead-letter queue for operator intervention.
Schema (migration 000016, idempotent):
- retry_count INTEGER NOT NULL DEFAULT 0
- next_retry_at TIMESTAMPTZ
- last_error TEXT
- idx_notification_events_retry_sweep partial index
(next_retry_at) WHERE status='failed' AND next_retry_at IS NOT NULL
Dead rows clear next_retry_at so the index stops matching them.
Service contract:
- NotificationService.RetryFailedNotifications drives 2^n-minute
exponential backoff capped at 1h (notifRetryBackoffCap) with
5-attempt budget (notifRetryMaxAttempts).
- Exhaustion (RetryCount >= notifRetryMaxAttempts-1) promotes to
status='dead' via MarkAsDead.
- Non-terminal failures record via RecordFailedAttempt.
- Success path promotes to 'sent' without touching retry_count
(audit preserves "delivered on attempt N").
- Missing-notifier branch defensively promotes to 'sent' to avoid
wedging a row on a deleted channel.
- RequeueNotification operator escape hatch atomically resets
retry_count -> 0, next_retry_at -> NULL, last_error -> NULL,
status -> pending via notifRepo.Requeue.
Scheduler:
- New always-on notificationRetryLoop wired into the base loop set at
CERTCTL_NOTIFICATION_RETRY_INTERVAL (default 2m).
- sync/atomic.Bool idempotency guard.
- sync.WaitGroup shutdown drain via WaitForCompletion.
StatsService:
- SetNotifRepo setter pattern preserves 9 pre-existing
NewStatsService call sites (main.go + stats_test.go + 8 digest
tests) without touching the constructor signature.
- DashboardSummary.NotificationsDead populated via
notifRepo.CountByStatus(ctx, "dead") — nil-safe when unwired
(reports zero on systems without a notification repository).
- CountByStatus error is non-fatal (dashboard summary is
best-effort for this field).
- Prometheus certctl_notification_dead_total counter emitted from
the same snapshot.
Handler:
- New POST /api/v1/notifications/{id}/requeue endpoint.
- dead status surfaces to MCP + CLI.
Frontend:
- NotificationsPage gains two-tab toolbar ("All" / "Dead letter")
with queryKey: ['notifications', activeTab] so switching tabs
doesn't serve stale data until the 30s refetch.
- Dead rows surface "Retry {n}/5" + truncated last_error with
full-text title tooltip.
- Requeue mutation wrapped as
mutationFn: (id: string) => requeueNotification(id)
to prevent react-query v5's positional context argument from
leaking into the API client — pinned against future refactors
by strict-match toHaveBeenCalledWith('notif-dead-001') in
NotificationsPage.test.tsx:181.
Closes I-005.
M21 adds server-side active TLS scanning of CIDR ranges with concurrent
probing, sentinel agent pattern for pipeline reuse, and full CRUD API for
scan targets. M22 adds Prometheus exposition format endpoint alongside
existing JSON metrics. Comprehensive documentation audit updates all docs
to reflect 91 endpoints, 19 tables, 6 scheduler loops, and 900+ tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>