Signing up mailed a link and nothing else, so a visitor who signed up on one
device and read the mail on another had to leave the page the studio was open
on, or give up and stay a guest. The letter now carries six digits as well, and
the verify dialog — the face a fresh signup already lands on — takes them.
Backend, one row is both proofs. `createEmailVerification` mints the token as it
did and a `randomInt(0, 1_000_000)` code padded to six, and returns `{ token,
code }`; `sendVerification` passes both to the mailer, which puts the code first
and the link second. The code's clock is `created_at + CODE_TTL_S` (15 minutes)
and the link keeps the row's own 24-hour `expires_at`: two clocks over one row,
so the code needs no expiry column of its own. That row's `code` is NULL for
anything minted before this commit, a value no typed guess can match, so an
in-flight link from the old mail still works and its owner simply has no code to
type. `db.ts` adds both columns with `PRAGMA table_info` + `ALTER TABLE` rather
than a rebuild, and sets `attempts` to 0.
`verifyEmailCode(userId, code)` answers 'ok' | 'bad' | 'stale' | 'locked', and
the shape of the answer is the point. 'stale' is both "no live code" and "too
old", so the caller learns nothing about which; 'locked' is the spent-attempts
state, which only a fresh letter leaves. The attempt is counted BEFORE the
comparison is trusted, so an interrupted request cannot hand back a guess nobody
paid for; five (MAX_CODE_ATTEMPTS) is the cap, which is what keeps a six-digit
secret from being walked through at a hundred requests a second. The comparison
itself is `timingSafeEqual` behind a length check, the same pair the password
path uses. On success the row is deleted and `email_verified` set, so the same
row spends the link with the code — one proof, one use.
The route is `POST /api/auth/verify-code`, a POST and not a GET like the link
because a code in a query string lands in every proxy log on the way. It reads
`auth`, not `requirePro`: the whole point of it is the account that has not
passed the gate yet. Input must be exactly six digits before anything else
happens, so the counter only ever counts real guesses; a wrong or stale code is
400, a locked one 429 with `retry-after: 900`, and an already-verified caller
gets 200 without touching the row. No limiter of its own: the cap lives with the
secret on the row, and a fresh code costs one of the three resends an hour, so
five guesses per code is the budget either way.
On the web side `api.verifyCode` posts the code, and the dialog's verify face
swaps its resend button for a code box plus a smaller resend beside it: the box
is `inputMode="numeric"`, `autoComplete="one-time-code"`, `maxLength 6`, and
strips non-digits as they are typed, so the number pad comes up on a phone and
nothing can paste a password into it. The submit button is disabled until six
digits are there. The two answers a visitor can actually act on get sentences of
their own (`auth.codeBad`, `auth.codeLocked`); everything else is shown as it
comes. The link path is untouched and still works, and the dialog keeps its
"Tôi đã xác thực xong" escape in no place at all — it verified nothing, so
closing the dialog and asking again covers the same ground.
The comment in `docker/.env.example` now says the letter carries both, since a
deployment without a relay writes both to the api log.
Verified:
backend `npm test` — 180 passed, 0 failed. The new section in security.mjs
drives the route end to end against the source: signup leaves a six-digit
code beside the link, a wrong code verifies nothing and leaves the account
unproven, a five-digit body is refused, a signed-out caller cannot type one,
the mailed code verifies, spending it spends the link, five wrong guesses
lock the code out and the right code then does not help, a resent letter
hands out a fresh code that is not locked out by the old guesses, and a code
aged past its quarter hour is refused.
otp-code-probe.cjs (scratchpad) — 10 PASS, 0 FAIL on http://localhost:8090
against the rebuilt app and api, no page errors: a fresh signup lands on the
verify face with the box ready, a wrong code says so and the account stays a
guest, the mailed code unlocks PRO, and a proven address is not asked again
on the next login.
Regressions, 0 fail: landing-test.cjs 172, pro-gate-test.cjs 27,
award-column-probe.cjs 18, tone-curve-probe.cjs 33. web tsc --noEmit clean.
ponytail: the code rides `created_at` rather than an `expires_at` of its own, so
the link's 24 hours and the code's 15 minutes are one column read twice; the day
the two need to drift apart independently, the column is the thing to split. The
route carries no per-IP limiter, only the per-row cap — a stranger can burn one
account's five guesses, which costs that owner a resend, and a limiter keyed on
the address would be the next thing to add if that turns out to be cheap for an
attacker. The code is not usable from another browser: it verifies the session
that asked for it, which is the behaviour the request asked for and not a gap.
RecipesCam web — self-contained stack
A Docker-hosted web build of RecipesCam. Everything it needs is in this folder: move it to another machine, run two commands, and the app is up. It does not need the React Native project around it.
cp .env.example .env
docker compose up -d --build
# → http://localhost:8090
What runs where
| Service | Image | Role |
|---|---|---|
frontend |
nginx:1.27-alpine (built by frontend/Dockerfile) |
Static SPA + /api/ reverse proxy |
api |
node:22-slim (built by backend/Dockerfile) |
Accounts + saved recipes, SQLite on ./data |
frontend resolves api through Docker's embedded DNS and proxies /api/* to
it — that is why the API container is named api and why it is not published on
the host. Only ${WEB_PORT:-8090} is exposed.
Photos never leave the browser. The CanvasKit render pipeline (grade, frame, watermarks, JPEG encode) runs in the visitor's tab; the API only stores recipes as JSON.
Layout
docker-compose.yml the stack
.env.example WEB_PORT
data/ SQLite (created on first run, gitignored)
backend/ Fastify + better-sqlite3 API, own Dockerfile
frontend/ Vite + React + CanvasKit SPA, own Dockerfile + nginx.conf
shared/ vendored copies of the app's types + utils (see below)
src/engine/ skiaShim.ts (CanvasKit) + exportEngine.ts (render pipeline)
+ session.ts (localStorage/IndexedDB studio persistence)
Vendored files
frontend/shared/{types/index.ts,utils/*.ts} are byte-identical copies of
src/types/index.ts and ten src/utils/*.ts files from the React Native
project (@shopify/react-native-skia is aliased to src/engine/skiaShim.ts in
vite.config.ts + tsconfig.json, so those files compile unchanged):
cinemaShader colorUtils defaultRecipes exifWrite frameUtils jpegDpi
paramDefs recipeShare skiaImage toneShader.
The landing page needs no CDN: frontend/public/assets/fonts/*.woff2 are the
seven self-hosted faces behind the three font groups the Themes menu offers
(Plus Jakarta Sans / Inter / JetBrains Mono, Fraunces / Be Vietnam Pro /
Courier Prime, Be Vietnam Pro / Space Mono — all SIL OFL, pulled from Google
Fonts, vietnamese + latin + latin-ext subsets), and
frontend/public/assets/samples/s*.jpg are the six placeholder negatives the
film strip, preset tester and QR card show (swap them for real graded stills
whenever we have them). Its one foreign request is the QR image from
api.qrserver.com, which degrades to an empty slot offline.
When the app changes one of them, copy it back in — the renderer is only "parity" for as long as these stay in sync:
cd <repo>/docker/frontend/shared/utils
cp <repo>/src/utils/<name>.ts .
Operations
docker compose logs -f api # API log
docker compose restart api # after backend/src changes (rebuild: --build)
docker compose down # stop; ./data survives
Backup is the ./data folder — that is the whole database.
Checks
curl -s http://localhost:8090/api/health # {"ok":true}
curl -sI http://localhost:8090/ # 200, index.html
Then open the UI, drop a photo in, and confirm the preview shows the picture and
EXPORT downloads a JPEG that opens. The preview going solid black while the
export still reports a plausible size is the one failure mode worth knowing: it
means the CanvasKit GPU surfaces lost their shared GrDirectContext (see
frontend/src/engine/skiaShim.ts), and with no GPU the raster fallback renders
the same pipeline correctly, just slower.