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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+TypeScript REST API for **Bangkok Metropolitan Administration (BMA)** — a Human Resource
+Management System (HRMS) module managing organization structure (โครงสร้างอัตรากำลัง),
+positions, personnel profiles, salary/tenure calculations, and related HR workflows.
+
+**Stack:** Express.js · TypeORM (MySQL) · tsoa (controller-first OpenAPI generation) · Keycloak ·
+RabbitMQ · Redis · Elasticsearch · WebSocket (socket.io) · node-cron
+
+## Commands
+
+```sh
+npm install              # install deps (npm is canonical — CI/Docker use npm install, not pnpm)
+npm run dev               # dev server with hot reload (nodemon)
+npm run build              # tsoa spec-and-routes (regenerates src/routes.ts, src/swagger.json) + tsc
+npm run check               # tsc --noEmit
+npm start                    # run compiled dist/app.js
+npm run format                # prettier --write .
+
+npm run migration:generate src/migration/<name>   # generate a TypeORM migration
+npm run migration:run                               # run pending migrations
+node scripts/clean-migration-fk-idx.js               # strip FK_/idx_ lines from generated migrations (run after every generate)
+
+npm test                       # jest
+npm run test:watch              # jest --watch
+npm run test:coverage            # jest --coverage
+npx jest src/__tests__/unit/OrganizationController.spec.ts   # run a single test file
+```
+
+A repo note (README) documents building/testing the release pipeline locally with `act`
+(`act workflow_dispatch -W .github/workflows/release.yaml ...`), but the actual CI is Forgejo
+Actions (`.forgejo/workflows/`) and an OneDev buildspec (`.onedev-buildspec.yml`); both run
+`npm install && npm run build` and build `docker/Dockerfile`.
+
+**Note:** despite `pnpm-lock.yaml` being present in the repo, all CI/Docker paths use `npm`. Use
+`npm` for scripts and dependency changes unless told otherwise.
+
+## Architecture
+
+### Request flow: tsoa controllers → (optional) services → TypeORM repositories
+
+- Routes are **not** hand-written. `tsoa.json` globs `src/controllers/**/*Controller.ts` and
+  `npm run build` regenerates `src/routes.ts` (Express route registration, called via
+  `RegisterRoutes(app)` in `src/app.ts`) and `src/swagger.json` from tsoa decorators. **Any time
+  you add/change a controller method or its decorators, you must run `npm run build`** (or at
+  least `tsoa spec-and-routes`) or the route/swagger changes won't take effect.
+- In practice most controllers get their repositories directly via
+  `AppDataSource.getRepository(Entity)` in the constructor/method body rather than going through a
+  service layer — the codebase is controller-heavy (`OrganizationController.ts`,
+  `ImportDataController.ts`, `PositionController.ts`, `ReportController.ts` are each hundreds of
+  KB). `src/services/` exists for genuinely cross-cutting or heavier business logic (org command
+  execution, salary/tenure batch jobs, RabbitMQ, WebSocket) but is not a strict mandatory layer for
+  every endpoint.
+- All entities (`src/entities/`) extend `EntityBase` (`src/entities/base/Base.ts`), which supplies
+  `id` (UUID), `createdAt`/`lastUpdatedAt`, and creator/updater id+name audit columns — every table
+  is audited by default. `src/entities/mis/` holds legacy/external MIS-system table mappings
+  (read-mostly, prefixed `HR_*`); `src/entities/view/` holds TypeORM entities mapped onto SQL
+  views (`viewCurrentTenure*`, `viewDirector*`, etc.) used for computed/reporting reads.
+- Responses are wrapped in `HttpSuccess` (`src/interfaces/http-success.ts`, `{status, message,
+  result}`, Thai success message by default) or thrown as `HttpError` (`src/interfaces/
+http-error.ts`, carries an `HttpStatus` + Thai message) — the global error middleware
+  (`src/middlewares/error.ts`) catches thrown `HttpError`/exceptions and formats the response.
+  `src/interfaces/http-status.ts` is the status-code enum used everywhere instead of magic numbers.
+
+### Auth (three schemes, selected per-route via `@Security(...)`)
+
+All resolved in `expressAuthentication` (`src/middlewares/auth.ts`), which tsoa calls per-request
+based on the controller's `@Security` decorator:
+
+- `bearerAuth` — Keycloak JWT in `Authorization: Bearer <token>`. Verified either **offline**
+  (`AUTH_PUBLIC_KEY`, local RS256 verification via `fast-jwt`) or **online** (`AUTH_REALM_URL`
+  userinfo endpoint), selected by `AUTH_PREFERRED_MODE`. Populates `req.app.locals.logData` with
+  user/org-tree ids from the token for logging. Type: `RequestWithUser` (`src/middlewares/user.ts`).
+- `webServiceAuth` — `X-API-Key` header, resolved against the `ApiKey` entity in
+  `src/middlewares/authWebService.ts` (looks up allowed `apiNames`/org scope). Type:
+  `RequestWithUserWebService`.
+- `internalAuth` — `api-key`/`api_key`/`apikey` header checked against the `API_KEY` env var
+  (`src/middlewares/authInternal.ts`), for trusted internal services (e.g. the .NET HRMS system).
+- If `NODE_ENV !== "production"` and `AUTH_BYPASS` is set, auth is skipped entirely
+  (`{preferred_username: "bypassed"}`) — dev/test convenience only.
+- Role gating within `bearerAuth` routes uses `authRole()` (`src/middlewares/role.ts`) and the
+  `permission` helper (`src/interfaces/permission.ts`) which calls out to an external `/org/permission`
+  check via `CallAPI`.
+
+### Background work
+
+- **Cron jobs** are all registered inline in `src/app.ts` via `node-cron` (6-field: seconds
+  included), each wrapping a controller/service call in try/catch that only logs on failure —
+  daily org revision cache refresh, retirement status updates (Oct 1st), org DNA sync, tenure
+  recalculation, and posting retirement data to an external "Exprofile" system.
+- **RabbitMQ** (`src/services/rabbitmq.ts`) publishes org-structure change events
+  (`sendToQueueOrg` / `sendToQueueOrgDraft`); connects with infinite retry
+  (`setTimeout(runMessageQueue, 1000)` on failure) — don't add redundant retry logic around it.
+  Fire-and-forget from callers; don't block HTTP responses on publish.
+- **WebSocket** (`src/services/webSocket.ts`, `initWebSocket()`) for real-time push, initialized
+  before the HTTP server starts listening.
+- **`OrgStructureCache`** (`src/utils/OrgStructureCache.ts`) is an in-memory TTL cache (30 min) for
+  org-tree reads, keyed by revision+root id, initialized/destroyed alongside the app lifecycle. Use
+  it instead of re-querying the same org structure repeatedly within a request.
+- **`LogMemoryStore`** (`src/utils/LogMemoryStore.ts`) plus `src/middlewares/logs.ts` build a
+  per-request log sequence (including DB queries logged via the custom TypeORM `Logger` in
+  `src/database/data-source.ts`) — this is what's shipped to Elasticsearch for auditing.
+
+### Database
+
+- MySQL via TypeORM, connection pool configured in `src/database/data-source.ts`
+  (`connectionLimit`, `poolSize`, `maxQueryExecutionTime` all env-tunable). `synchronize` is
+  always `false` — schema changes go through migrations only.
+- Timezone is pinned to Bangkok (`+07:00`) at the connection level; store/compare datetimes
+  accordingly rather than assuming UTC.
+- After `migration:generate`, always run `node scripts/clean-migration-fk-idx.js` to strip
+  auto-generated `FK_*`/`idx_*` lines from the migration's `up`/`down` — this is a hard project
+  convention, not optional cleanup.
+
+### Data dictionary
+
+`docs/data-dictionary/` holds a generated schema data dictionary (`.docx`); the `data-dictionary`
+skill / `scripts/generate-docx.py` regenerate it from `docs/data-dictionary/generate-prompt.md`.
+
+## Conventions
+
+- Files/classes: PascalCase (`OrganizationController.ts`). Variables/functions: camelCase.
+- DB column comments and HTTP error/success messages are written in **Thai** — keep this
+  consistent when adding columns or throwing `HttpError`.
+- Services must not import from `controllers/`; keep services HTTP-agnostic (no `HttpError`/
+  `HttpSuccess` imports in `src/services/`).
+- Don't use `moment` for new code (native `Date`/`Intl` only — `moment` remains for legacy call
+  sites). Don't bypass tsoa validation with manual `req.body` casting.
+- `tsconfig.json` excludes `src/__tests__/**` and `*.spec.ts`/`*.test.ts` from the production
+  build; tests only run under `ts-jest` via `jest.config.js` (path alias `@/` → `src/`).