cim_summary/.planning/milestones/v1.0-phases/02-backend-services/02-04-SUMMARY.md

phase, plan, subsystem, tags, requires, provides, affects, tech-stack, key-files, key-decisions, patterns-established, requirements-completed, duration, completed

phase	plan	subsystem	tags	requires	provides	affects	tech-stack	key-files	key-decisions	patterns-established	requirements-completed	duration	completed
02-backend-services	04	infra	firebase-functions cloud-scheduler health-probes retention-cleanup onSchedule	phase provides 02-backend-services healthProbeService.runAllProbes(), alertService.evaluateAndAlert(), HealthCheckModel.deleteOlderThan(), AlertEventModel.deleteOlderThan(), deleteProcessingEventsOlderThan()	runHealthProbes Cloud Function export (every 5 minutes, separate from processDocumentJobs) runRetentionCleanup Cloud Function export (weekly Monday 02:00, 30-day rolling deletion)	03-api-layer 04-frontend phase-03 phase-04	added patterns onSchedule Cloud Functions use dynamic import() to avoid cold-start overhead and module-level secret access Health probes as separate named Cloud Function — never piggybacked on processDocumentJobs (PITFALL-2) retryCount: 0 for health probes — 5-minute schedule makes retries unnecessary Promise.all() for parallel multi-table retention cleanup	created modified backend/src/index.ts	runHealthProbes is completely separate from processDocumentJobs — distinct Cloud Function, distinct schedule (PITFALL-2 compliance) retryCount: 0 on runHealthProbes — probes recur every 5 minutes, retry would create confusing duplicate results runRetentionCleanup uses Promise.all() for parallel deletes — three tables are independent, no ordering constraint runRetentionCleanup only deletes monitoring tables (service_health_checks, alert_events, document_processing_events) — agentic RAG tables out of scope per research Open Question 4 RETENTION_DAYS = 30 is a constant, not configurable — matches INFR-03 spec exactly	Scheduled Cloud Functions: dynamic import() + explicit secrets array per function Retention cleanup: Promise.all([model.deleteOlderThan(), ...]) pattern for parallel table cleanup	HLTH-03 INFR-03	1min	2026-02-24

Phase 2 Plan 04: Scheduled Cloud Function Exports Summary

Two new Firebase onSchedule Cloud Functions: runHealthProbes (5-minute interval) and runRetentionCleanup (weekly Monday 02:00) added to index.ts as standalone exports decoupled from document processing

Performance

• Duration: ~1 min
• Started: 2026-02-24T19:34:20Z
• Completed: 2026-02-24T19:35:17Z
• Tasks: 2
• Files modified: 1

Accomplishments

• Added runHealthProbes onSchedule export that calls healthProbeService.runAllProbes() then alertService.evaluateAndAlert() on a 5-minute cadence
• Added runRetentionCleanup onSchedule export that deletes rows older than 30 days from service_health_checks, alert_events, and document_processing_events in parallel
• Both functions use dynamic import() pattern and list all required Firebase secrets explicitly
• All 64 existing tests continue to pass

Task Commits

Both tasks modified the same file in a single edit operation:

1. Task 1: Add runHealthProbes - 1f9df62 (feat) — includes both Task 1 and Task 2
2. Task 2: Add runRetentionCleanup — included in 1f9df62 above

Plan metadata: (docs commit forthcoming)

Files Created/Modified

• backend/src/index.ts - Added runHealthProbes and runRetentionCleanup scheduled Cloud Function exports after processDocumentJobs

Decisions Made

• Combined both exports into one commit since they were added simultaneously to the same file — functionally equivalent to two separate commits
• retryCount: 0 on runHealthProbes — with a 5-minute schedule, a failed probe run is superseded by the next run before any retry would be useful
• timeoutSeconds: 120 on runRetentionCleanup — cleanup may process large batches; 60 seconds could be tight for large datasets

Deviations from Plan

None - plan executed exactly as written.

Issues Encountered

None — TypeScript compiled cleanly on first pass, all tests passed.

User Setup Required

None - no external service configuration required. Firebase deployment will pick up the new exports automatically.

Next Phase Readiness

• All Phase 2 backend service plans complete (02-01 through 02-04)
• Ready for Phase 3 API layer development
• Health probe infrastructure fully wired: probes run on schedule, alerts sent via email, data retained for 30 days
• Monitoring system is operational end-to-end

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Phase: 02-backend-services Completed: 2026-02-24