Closes one 2026-04-24 audit finding (P2):
- cat-s6-efc7f6f6bd50: 30 strings.Contains(err.Error(), ...) sites
in internal/api/handler/ — brittle to repository-layer message
changes, untyped against the actual failure mode.
Approach (Option B from prompt design notes):
- New typed sentinels in internal/repository/errors.go:
ErrNotFound, ErrForeignKeyConstraint
IsForeignKeyError(err) helper (the only place substring
matching at the lib/pq boundary is allowed; isolates the
DB-driver string knowledge to one function).
- New typed sentinel in internal/domain/errors.go:
ErrValidation (reserved for future per-entity validation
wrappers; not yet used by all handlers).
- 49 sites in internal/repository/postgres/*.go updated to wrap
sql.ErrNoRows-derived errors via fmt.Errorf("...: %w",
repository.ErrNotFound).
- 18 not-found handler sites + 2 FK-constraint handler sites
refactored to errors.Is(err, repository.ErrNotFound) /
repository.IsForeignKeyError(err).
- 23 inline `fmt.Errorf("X not found")` test fixtures across
handler tests rewrapped to wrap repository.ErrNotFound.
- test_utils.go::ErrMockNotFound rewrapped to wrap
repository.ErrNotFound; renewal_policy.go closure docblock
updated to reflect the new convention.
- integration test mockJobRepository.Get wraps repository.ErrNotFound.
CI regression guardrail:
- .github/workflows/ci.yml::"Forbidden strings.Contains(err.Error())
regression guard (S-2)" greps for the three patterns ("not found",
"violates foreign key", "RESTRICT") under internal/api/handler/
and fails the build on regression.
Verification:
- go build ./... — clean
- go vet ./... — clean
- go test ./... -short -count=1 — all packages pass (handler +
repository + service + integration)
- golangci-lint v2.11.4 run ./... — 0 issues
- S-2 guardrail dry-run on post-fix tree → empty (good)
- All sibling guardrails (S-1, G-3, D-1+D-2, B-1, L-1, H-1, C-1, F-1, P-1) pass
Audit findings closed:
- cat-s6-efc7f6f6bd50 (P2)
Deferred follow-ups:
- 6 domain-specific substring patterns still inline in handlers
("cannot approve", "cannot reject", "cannot be parsed",
"no certificates found", "challenge password", "invalid"/
"required" validation chains in profiles + agent_groups). Each
needs its own typed sentinel, scoped per service. Documented
by the S-2 CI guardrail's allowlist for closure-comments only.
- Per-entity not-found sentinels (Option A — ErrCertificateNotFound,
ErrAgentNotFound, etc.) deferred. Generic ErrNotFound covers the
current dispatch needs; per-entity precision would let handlers
return entity-aware error bodies without a domain.Type field,
but not blocking.
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.
Collapse CancelJobWithContext into CancelJob; eliminate 10 context.Background()
hits across the Job+Notification+Audit service cluster by threading ctx
through their handler-facing service interfaces.
Services (ctx-first):
- service/job.go: ListJobs, GetJob, CancelJob, ApproveJob, RejectJob now
accept ctx; the CancelJobWithContext wrapper is removed (handler callers
continue to invoke CancelJob, now ctx-aware).
- service/notification.go: ListNotifications, GetNotification, MarkAsRead
accept ctx.
- service/audit.go: ListAuditEvents, GetAuditEvent accept ctx.
Handlers (interface + callsites):
- handler/jobs.go, handler/notifications.go, handler/audit.go: local
service interfaces updated, r.Context() threaded at every callsite.
Tests:
- Mock services updated to match the new interfaces (ctx accepted and
ignored via '_ context.Context' first parameter; Fn closure fields
unchanged).
- job_test.go / notification_test.go callsites thread context.Background()
to match production shape.
Verification:
go build ./... ok
go vet ./... ok
go test -short ./... ok
go test -race -short ./... ok
golangci-lint run ./... 0 issues
Locked decisions from the M-2 plan:
D-1 ctx-only signatures (no dual forms)
D-4 preserve handler method names facing the router
D-5 domain types stay ctx-free
Audit complete. Commit: 855124a9d9. Sections: 12. Findings: 2/7/10/4/6.
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