---
type: entity
tags: [parking, stack, auth, offline-first]
sources: [parking-system-architecture]
updated: 2026-06-15
---

# Local JWT Auth

Authentication and authorization, kept **fully local** — a direct consequence of
[[offline-first]] (an air-gapped park cannot reach an external identity provider; see
[[logto-zitadel-oidc]] for the rejected alternative). (See [[parking-system-architecture]] §2.)

- `@fastify/jwt` signs tokens with a **local secret** (symmetric HMAC). The server **refuses to
  start** without a strong `JWT_SECRET` (≥32 chars, no placeholder) — there is deliberately no
  insecure default.
- **Session lifetime: valid until explicit logout — no time expiry** (decision 2026-06-15).
  Booth reality breaks any fixed clock: relief arrives late, fails to show, or one operator is
  forced to work two shifts in a row — a token that expired mid-duty would strand an active
  operator. So the login persists until logout; a **[[shift]] is a separate, explicit boundary**,
  not tied to token lifetime. (Superseded the earlier "8h expiry, bound to a shift" assumption.)
  > ⚠️ Code still mints an 8h-expiry token — this page records the decided design; the server
  > change (drop `expiresIn`, persist until logout) is pending.
- A `users` table in [[sqlite]] holds **bcrypt** password hashes plus a **role** column. The
  first admin is seeded via `pnpm --filter @parking/server seed-admin` (no bootstrap endpoint).
- Authorization = a simple `preHandler` role guard per route: **admin / operator / cashier /
  readonly**. No Casbin or full RBAC engine needed at this scale.

## Cookie session (browser auth)

The SPA never sees the JWT. Login (`POST /api/auth/login`) verifies bcrypt and sets two cookies:

- **`parking_token`** — the JWT, **HttpOnly + SameSite=Strict** (+ `Secure` when
  `NODE_ENV=production`). JS can't read it; `@fastify/jwt` reads it from the cookie, not the
  `Authorization` header.
- **`parking_csrf`** — a random token, **readable** by JS. The JWT also carries a matching `csrf`
  claim. On every mutation the SPA echoes the cookie in the **`X-CSRF-Token`** header; the guard
  requires header == cookie == the signed claim (**double-submit CSRF**). Safe reads are exempt.

Routes: `login`, `logout` (clears cookies), `me` (bootstraps SPA session on load). The dev
[[react-vite-spa|Vite]] proxy and the prod **nginx** reverse proxy keep the SPA and API
**same-origin**, so the cookies work without CORS. (This replaced an earlier dev-only
`SETUP_AUTH_BYPASS` shim, now removed.)

> **Open decision:** moving from the symmetric secret to an **asymmetric key (RS256/EdDSA)** so
> verifying hosts hold only a public key — [[open-questions]] #7. Relevant before any
> multi-host/multi-lane deployment.

Part of the [[technology-stack]]. License: MIT.