a45c801884
Until now the open-alert key was (host_id, kind, resolved_at IS NULL). A host with two source groups both failing collapsed onto one backup_failed row — second failure bumped last_seen_at and overwrote the message but never re-fan-out. Operators saw one alert that appeared to flap, not two distinct broken things. Schema changes (column-level ALTER, no rebuild): - 0015 jobs.source_group_id (FK → source_groups, ON DELETE SET NULL, index). Populated for backup jobs in CreateJob. - 0016 alerts.dedup_key (NOT NULL DEFAULT ''). The old alerts_open partial index gets dropped and replaced with a UNIQUE partial index on (host_id, kind, dedup_key) WHERE resolved_at IS NULL — the index is now the actual dedup primitive. Plumbing: - RaiseOrTouch / AutoResolve / Alert struct gain dedup_key. - engine.JobFinishedEvent gains SourceGroupID; handleJobFinished passes it through for backup_failed only (forget/prune/check stay repo-scoped with key=''). - ws.handler reads SourceGroupID off the freshly-loaded job row. - dispatchJobWithPayload gains a *string sourceGroupID arg; the per-group Run-now path and schedule.fire path pass &g.ID. Test coverage: TestRaiseOrTouchDedupsPerSourceGroup proves two distinct groups produce two distinct open alerts and that resolving one does not auto-resolve the other. Dev tool: cmd/_fake_alert gains -dedup-key flag.