# supabase_test — Supabase + .NET + React boilerplate

Reusable template for a per-user CRUD app backed by Supabase Auth + Postgres. The stack:

- **React** (Vite + TypeScript) SPA in the browser — uses `@supabase/supabase-js` only for authentication.
- **ASP.NET Core 9** Web API — validates Supabase-issued JWTs against the project's JWKS and owns all database access.
- **Supabase** — hosted auth + Postgres.

The .NET backend is the sole gateway to data. The browser never talks to PostgREST. Row-level security stays off; the backend enforces ownership in SQL.

## Architecture at a glance

```
[React SPA]  ──(bearer JWT)──▶  [ASP.NET Core Web API]  ──(Npgsql / EF Core)──▶  [Supabase Postgres]
      │                                   ▲
      └──(auth handshake with supabase-js)─┘
      └────(JWKS fetch via OpenID discovery)─────┘
```

- React reads its session with `supabase.auth.getSession()` and attaches `Authorization: Bearer <access_token>` to every `/api/todos*` request.
- The .NET backend validates the JWT asymmetrically against `https://<ref>.supabase.co/auth/v1/.well-known/openid-configuration` — no shared secret. The `sub` claim (a UUID) becomes `user_id` on every query.
- Every mutation is scoped by `WHERE user_id = @currentUser`. Non-owned rows return 404 (not 403) — no existence leak.
- Backend connects to Postgres via Supabase's **session pooler** (`aws-<n>-<region>.pooler.supabase.com:5432`). The direct DB host is IPv6-only for new Supabase projects and unreachable from IPv4-only environments.

## Repo layout

```
backend/                              ASP.NET Core 9 Web API
├── Program.cs                        DbContext, JWT auth, controllers, CORS (dev-only), SPA fallback, /health
├── Controllers/TodosController.cs    GET / POST / PATCH / DELETE, [Authorize]-gated
├── Data/AppDbContext.cs              EF Core context (single Todo entity)
├── Models/Todo.cs
├── Dtos/                             Wire DTOs (never expose user_id)
├── appsettings.json                  Shared, non-secret defaults
├── appsettings.Development.example.json   Template with placeholders
└── appsettings.Development.json      REAL values, gitignored

frontend/                             Vite + React + TypeScript SPA
├── src/lib/supabase.ts               createClient(url, publishable_key)
├── src/lib/api.ts                    Authed fetch wrapper (attaches Bearer)
├── src/auth/AuthProvider.tsx         Session state via onAuthStateChange
├── src/auth/SignIn.tsx               Email + password sign-in / sign-up
├── src/todos/TodoList.tsx            List + add + toggle + delete
├── src/App.tsx / main.tsx            Route between SignIn and TodoList
├── .env.example                      Template with placeholders
└── .env.local                        REAL values, gitignored

migrations/001_create_todos.sql       Plain SQL applied once against Supabase Postgres
docs/superpowers/specs/               Original design spec
docs/superpowers/plans/               Implementation plan
Dockerfile / docker-compose.yml       Coolify-ready single-image packaging
.dockerignore                         Keeps host bin/, obj/, node_modules/ out of the build context
deploy.json                           Coolify per-app config (gitignored — holds runtime secrets)
```

## Configuring for a new Supabase project

**Six values** change per Supabase project. Everything else is project-agnostic — same schema, same auth flow, same code.

| Value | Where to get it (Supabase dashboard) | Where it goes |
|---|---|---|
| Project URL (e.g. `https://<ref>.supabase.co`) | Project Settings → API → Project URL | `backend/appsettings.Development.json` (`Supabase:MetadataAddress`, `Supabase:Issuer`) and `frontend/.env.local` (`VITE_SUPABASE_URL`) |
| Publishable (anon) key | Project Settings → API → Project API Keys → `publishable` | `frontend/.env.local` (`VITE_SUPABASE_PUBLISHABLE_KEY`) |
| Secret (service-role) key | Project Settings → API → Project API Keys → `secret` | NOT used by the app; only useful for admin-API E2E tests |
| Database password | Set once during project creation; can be reset | `backend/appsettings.Development.json` (part of `ConnectionStrings:Postgres`) |
| Session pooler hostname | Project Settings → Database → Connection string → **Session pooler** tab (port 5432) | `backend/appsettings.Development.json` (host + username in `ConnectionStrings:Postgres`) |
| Pooler username | Same tab; format is `postgres.<project-ref>` — always postgres + dot + project ref | Same connection string |

### Concrete steps for a new project

1. **Copy the templates and fill them in:**
   ```bash
   cp backend/appsettings.Development.example.json backend/appsettings.Development.json
   cp frontend/.env.example frontend/.env.local
   ```
   Substitute the six values above.
2. **Apply the migration** against the new Supabase project:
   ```bash
   PGPASSWORD='<db-password>' psql \
     "host=aws-<n>-<region>.pooler.supabase.com port=5432 dbname=postgres user=postgres.<project-ref> sslmode=require" \
     -f migrations/001_create_todos.sql
   ```
   (Or paste the SQL into the Supabase SQL Editor.)
3. **Disable email confirmation for dev:** Supabase dashboard → Authentication → Providers → Email → toggle **Confirm email** OFF. Otherwise `supabase.auth.signUp` won't return a session and the SignIn UI hangs at "Working…" while a confirmation email is queued (and often silently rate-limited to 2–4/hour on the default SMTP).
4. **Install and run:**
   ```bash
   cd frontend && npm install
   # Terminal 1
   cd backend && dotnet run             # http://localhost:5057
   # Terminal 2
   cd frontend && npm run dev           # http://localhost:5173
   ```

## Config surface — every knob

### Backend (`backend/appsettings.Development.json`)

```json
{
  "ConnectionStrings": {
    "Postgres": "Host=aws-<n>-<region>.pooler.supabase.com;Port=5432;Database=postgres;Username=postgres.<ref>;Password=<db-password>;SSL Mode=Require;Trust Server Certificate=true"
  },
  "Supabase": {
    "MetadataAddress": "https://<ref>.supabase.co/auth/v1/.well-known/openid-configuration",
    "Issuer":          "https://<ref>.supabase.co/auth/v1",
    "Audience":        "authenticated"
  }
}
```

`Audience` is always `authenticated` for user-issued JWTs — do not change unless you're validating service-role tokens (you shouldn't be, in this app).

The backend's port comes from `backend/Properties/launchSettings.json` (`applicationUrl` — default `http://localhost:5057`). If you move the backend to a different port, also update `VITE_API_URL` and the CORS `WithOrigins(...)` clause in `Program.cs`.

### Frontend (`frontend/.env.local`)

```
VITE_SUPABASE_URL=https://<ref>.supabase.co
VITE_SUPABASE_PUBLISHABLE_KEY=sb_publishable_...
VITE_API_URL=http://localhost:5057
```

`VITE_API_URL` empty (or unset) means **same-origin** — used when the backend serves the built SPA from `wwwroot/` in production (Dockerfile path). Set it explicitly during local dev when frontend and backend run on different ports.

### Container / Coolify (`docker-compose.yml`)

Six env vars flow in from Coolify's env-var UI:

| Coolify env | Purpose |
|---|---|
| `VITE_SUPABASE_URL` | Baked into the client bundle at image-build time (compose `build.args`) |
| `VITE_SUPABASE_PUBLISHABLE_KEY` | Same |
| `DB_CONNECTION_STRING` | Runtime, mapped to `ConnectionStrings__Postgres` |
| `SUPABASE_METADATA_ADDRESS` | Runtime, mapped to `Supabase__MetadataAddress` |
| `SUPABASE_ISSUER` | Runtime, mapped to `Supabase__Issuer` |
| — | `Supabase__Audience` is hard-coded to `authenticated` in the compose |

The compose file also declares `SERVICE_FQDN_APP_8080: /`. Coolify substitutes this with the app's real domain and injects the matching Traefik routing labels — **only if `docker_compose_domains` is set on the Coolify application**. Skipping that field turns every request into a 404 (see the `deploying-to-coolify-via-api` skill for the fix).

## Data model

Single table:

```sql
create table public.todos (
  id           bigserial primary key,
  user_id      uuid        not null,           -- Supabase auth.users.id (JWT sub claim)
  title        text        not null check (length(title) between 1 and 500),
  completed    boolean     not null default false,
  created_at   timestamptz not null default now()
);
create index todos_user_id_created_at_idx on public.todos (user_id, created_at desc);
```

No FK to `auth.users` — decouples from Supabase's internal schema and avoids permission headaches at migration time.

## Extending the pattern

To add a new entity (e.g. `notes`), the same shape repeats:

1. Add a table with `user_id uuid not null` + a `(user_id, created_at desc)` index. Ship as `migrations/00N_create_notes.sql`.
2. Add `backend/Models/Note.cs`, `backend/Dtos/{NoteDto,CreateNoteRequest,UpdateNoteRequest}.cs`.
3. Register the DbSet in `AppDbContext` with `HasIndex(...)` matching the SQL index name.
4. Add `NotesController` — copy `TodosController` verbatim, swap entity/DTO names. Keep the `CurrentUserId()` + `WHERE user_id == userId` pattern for every read/write; that's what enforces per-user isolation without RLS.
5. Frontend: an `api.notes` object with `list/create/setX/remove` alongside the existing `api` todos block, plus a `NotesList` component modelled on `TodoList`.

The critical invariant, everywhere: **every query filters by `userId = CurrentUserId()`**. Missing that on a single endpoint leaks other users' data.

## Known gotchas (all bit us during initial build — documented so they don't bite you)

| Symptom | Cause | Fix |
|---|---|---|
| `connection to server at "db.<ref>.supabase.co" failed: Network is unreachable` | Direct DB host is IPv6-only on new Supabase projects; sandbox has no IPv6 egress | Use the session pooler (`aws-<n>-<region>.pooler.supabase.com`, port 5432, user `postgres.<ref>`) |
| `dotnet add package X` restore fails with `NU1202` | CLI grabbed a newer major version incompatible with `net9.0` | Pin: `dotnet add package X --version 9.*` |
| Sign-up hangs / "email rate limit exceeded" | Email confirmation ON; Supabase default SMTP limits to 2–4/hour | Toggle Auth → Providers → Email → **Confirm email** OFF for dev; or wire real SMTP |
| Sign-up rejects `@example.com` with `email_address_invalid` | Supabase blocklists disposable domains on the ordinary signup endpoint | For E2E scripts, use the admin API (`POST /auth/v1/admin/users` with `email_confirm:true`) — see `docs/superpowers/plans/2026-08-15-supabase-todo-app.md` Task 8 |
| Deploy on Coolify finishes green, live URL returns `404 page not found` | Missing / mis-shaped `docker_compose_domains` on the Coolify app | See the `deploying-to-coolify-via-api` skill: PATCH the array-form after the first deploy loads the compose file |
| Vite template's `index.css` styles fight your inline styles | Scaffolded `index.css` ships opinionated marketing styles (large h1, fixed `#root` width) | Replace with the minimal reset in `frontend/src/index.css` |
| Backend port 5000 collisions across dev sessions | Common default for other Linux services / stale processes | This project uses `5057` — check the same for any port you pick |

## What NOT to change without thinking

- **RLS off** is a deliberate choice. If you enable RLS on `public.todos`, you must also either (a) write `USING (auth.uid() = user_id)` policies, or (b) have the backend run as a role with `BYPASSRLS`. Otherwise the backend's own queries stop returning rows.
- The **DTO response shape** deliberately omits `user_id`. Adding it back exposes the caller's own id (harmless) but invites confusion.
- **`RequireHttpsMetadata = true`** on the JwtBearer options. If you're testing against a non-HTTPS Supabase project (there is no such thing in practice), set to false — otherwise leave it. This prevents downgrade attacks on the JWKS fetch.
- **`MapInboundClaims = false`** — keeps the raw `sub` claim instead of remapping to `ClaimTypes.NameIdentifier`. If you flip this, update the `CurrentUserId()` helper.

## Related skills / docs

- `docs/superpowers/specs/2026-08-15-supabase-todo-app-design.md` — the original design decisions and out-of-scope list.
- `docs/superpowers/plans/2026-08-15-supabase-todo-app.md` — the 17-task implementation plan, including manual E2E verification recipes for backend (curl) and frontend (Playwright).
- Global skill: `creating-supabase-app-from-boilerplate` — clones this repo and reconfigures it against a new Supabase project.
- Global skill: `preparing-dotnet-react-app-for-coolify` — the Dockerfile + compose pattern this repo already implements.
- Global skill: `deploying-to-coolify-via-api` — how the Coolify project + application were created; run again against a new project or copy `deploy.json` and change the values.