cim_summary/.planning/milestones/v1.0-phases/01-data-foundation/01-01-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
01-data-foundation	01	database	supabase postgresql migrations typescript monitoring health-checks alerts		service_health_checks table with status CHECK constraint, JSONB probe_details, checked_at column alert_events table with alert_type/status CHECK constraints, lifecycle timestamps HealthCheckModel TypeScript class with CRUD static methods AlertEventModel TypeScript class with CRUD static methods Barrel exports for both models and their types from models/index.ts	01-02 (Phase 1 Plan 2 — next data foundation plan) Phase 2 (health probe services will write to service_health_checks) Phase 2 (alert service will write to alert_events and use findRecentByService for deduplication) Phase 3 (API endpoints will query both tables)	added patterns Static class model pattern (no instantiation — all methods are static async) getSupabaseServiceClient() called per-method, never cached at module level PGRST116 error code handled as null return (not an exception) Input validation in model create() methods before any DB call Record<string, unknown> for JSONB fields (no any types) Named Winston logger import import { logger } from '../utils/logger' IF NOT EXISTS on all DDL (idempotent forward-only migrations) TEXT + CHECK constraint pattern for enums (not PostgreSQL ENUM types)	created modified backend/src/models/migrations/012_create_monitoring_tables.sql backend/src/models/HealthCheckModel.ts backend/src/models/AlertEventModel.ts backend/src/models/index.ts	TEXT + CHECK constraint used for status/alert_type columns (not PostgreSQL ENUM types) — consistent with existing project pattern getSupabaseServiceClient() called per-method (not module-level singleton) — follows Research finding about Cloud Function cold start issues checked_at column added to service_health_checks separate from created_at — records actual probe run time, not DB insert time Forward-only migration only (no rollback scripts) — per user decision documented in CONTEXT.md RLS enabled on both tables with no explicit policies — service role key bypasses RLS; user-facing policies deferred to Phase 3	Model static class: all methods static async, getSupabaseServiceClient() per-method, PGRST116 → null Input validation before Supabase call: non-empty string check, union type allowlist check Error re-throw with method prefix: 'HealthCheckModel.create: ...' for log traceability deleteOlderThan(days): compute cutoff in JS then filter with .lt() — Supabase client does not support date arithmetic in filters	INFR-01 INFR-04	8min	2026-02-24

Phase 01 Plan 01: Data Foundation Summary

SQL migration + TypeScript model layer for monitoring: service_health_checks and alert_events tables with HealthCheckModel and AlertEventModel static classes using getSupabaseServiceClient() per-method

Performance

• Duration: ~8 min
• Started: 2026-02-24T16:29:39Z
• Completed: 2026-02-24T16:37:45Z
• Tasks: 2
• Files modified: 4

Accomplishments

• Created migration 012 with both monitoring tables, CHECK constraints on all enum columns, JSONB columns for flexible metadata, INFR-01 required created_at indexes, composite indexes for dashboard queries, and RLS on both tables
• Created HealthCheckModel with 4 static methods: create (with input validation), findLatestByService, findAll (with optional filters), deleteOlderThan (30-day retention)
• Created AlertEventModel with 6 static methods: create (with validation), findActive, acknowledge, resolve, findRecentByService (deduplication support for Phase 2), deleteOlderThan
• Updated models/index.ts with barrel exports for both model classes and all 4 types

Task Commits

Each task was committed atomically:

1. Task 1: Create monitoring tables migration - ad6f452 (feat)
2. Task 2: Create HealthCheckModel and AlertEventModel with barrel exports - 4a620b4 (feat)

Plan metadata: (docs commit — see below)

Files Created/Modified

• backend/src/models/migrations/012_create_monitoring_tables.sql - DDL for service_health_checks and alert_events tables with indexes and RLS
• backend/src/models/HealthCheckModel.ts - CRUD model for service_health_checks table, exports ServiceHealthCheck and CreateHealthCheckData types
• backend/src/models/AlertEventModel.ts - CRUD model for alert_events table with lifecycle methods (acknowledge/resolve), exports AlertEvent and CreateAlertEventData types
• backend/src/models/index.ts - Added barrel exports for both new models and their types

Decisions Made

• TEXT + CHECK constraint used for status/alert_type columns (not PostgreSQL ENUM types) — consistent with existing project pattern established in prior migrations
• getSupabaseServiceClient() called per-method (not cached at module level) — per Research finding about potential Cloud Function cold start issues with module-level Supabase client caching
• checked_at column kept separate from created_at on service_health_checks — probe timestamp vs. DB write timestamp are logically distinct (Research Pitfall 5)
• No rollback scripts in migration — forward-only per user decision documented in CONTEXT.md

Deviations from Plan

None — plan executed exactly as written.

Issues Encountered

• Branch mismatch: Task 1 committed to gsd/phase-01-data-foundation, Task 2 accidentally committed to upgrade/firebase-functions-v7-nodejs22 due to shell context reset between Bash calls. Resolved by cherry-picking the Task 2 commit onto the correct GSD branch.
• Pre-existing TypeScript error in backend/src/config/env.ts (Type 'never' has no call signatures) — unrelated to this plan's changes, deferred per scope boundary rules.

User Setup Required

None — no external service configuration required. The migration file must be run against the Supabase database when ready (will be part of the migration runner invocation in a future phase or manually via Supabase dashboard SQL editor).

Next Phase Readiness

• Both tables and both models are ready. Phase 2 health probe services can import HealthCheckModel and AlertEventModel from backend/src/models immediately.
• The findRecentByService method on AlertEventModel is ready for Phase 2 alert deduplication.
• The deleteOlderThan method on both models is ready for Phase 2 scheduler retention enforcement.
• Migration 012 needs to be applied to the Supabase database before any runtime writes will succeed.

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Phase: 01-data-foundation Completed: 2026-02-24

Self-Check: PASSED

• FOUND: backend/src/models/migrations/012_create_monitoring_tables.sql
• FOUND: backend/src/models/HealthCheckModel.ts
• FOUND: backend/src/models/AlertEventModel.ts
• FOUND: .planning/phases/01-data-foundation/01-01-SUMMARY.md
• FOUND commit: ad6f452 (Task 1)
• FOUND commit: 4a620b4 (Task 2)