# Milestone 3: Auth Completeness (supabase-js Compatibility)

**Goal:** `supabase.auth.*` works correctly for the core flows real apps need.

**Depends on:** M0 (Security), M1 (Foundation)

---

## 3.1 — Missing Core Endpoints

### 3.1.1 POST /auth/v1/logout

**File:** `auth/src/handlers.rs` (new function), `auth/src/lib.rs` (add route)

```rust
pub async fn logout(
    State(state): State<AuthState>,
    db: Option<Extension<PgPool>>,
    Extension(auth_ctx): Extension<AuthContext>,
) -> Result<StatusCode, ApiError> {
    let claims = auth_ctx.claims.ok_or(ApiError::Unauthorized("Not authenticated".into()))?;
    let user_id = Uuid::parse_str(&claims.sub).map_err(|_| ApiError::Unauthorized("Invalid user ID".into()))?;
    let db = db.map(|Extension(p)| p).unwrap_or(state.db.clone());

    // Revoke all active refresh tokens for this user's current session
    sqlx::query("UPDATE refresh_tokens SET revoked = true WHERE user_id = $1 AND revoked = false")
        .bind(user_id)
        .execute(&db)
        .await?;

    // If Redis sessions are active, destroy them
    // if let Some(session_manager) = &state.session_manager {
    //     session_manager.delete_all_user_sessions(user_id).await.ok();
    // }

    Ok(StatusCode::NO_CONTENT)
}
```

Add route in `auth/src/lib.rs`:
```rust
.route("/logout", post(handlers::logout))
```

**supabase-js behavior:** `signOut()` calls `POST /auth/v1/logout` with the access token in the Authorization header. Expects 204 No Content.

### 3.1.2 GET /auth/v1/settings

Returns auth configuration that supabase-js reads during initialization:

```rust
pub async fn settings(
    State(state): State<AuthState>,
) -> Json<serde_json::Value> {
    Json(serde_json::json!({
        "external": {
            "google": state.config.google_client_id.is_some(),
            "github": state.config.github_client_id.is_some(),
            "azure": state.config.azure_client_id.is_some(),
            "gitlab": state.config.gitlab_client_id.is_some(),
            "bitbucket": state.config.bitbucket_client_id.is_some(),
            "discord": state.config.discord_client_id.is_some(),
        },
        "disable_signup": false,
        "mailer_autoconfirm": std::env::var("AUTH_AUTO_CONFIRM").map(|v| v == "true").unwrap_or(false),
        "sms_provider": "",
        "mfa_enabled": true,
    }))
}
```

### 3.1.3 POST /auth/v1/magiclink

Generates a one-time login token, sends it via email. When the user clicks the link, they hit `/auth/v1/verify?type=magiclink&token=...` which issues tokens.

```rust
pub async fn magiclink(
    State(state): State<AuthState>,
    db: Option<Extension<PgPool>>,
    Json(payload): Json<RecoverRequest>, // Reuses email-only request
) -> Result<Json<serde_json::Value>, ApiError> {
    let db = db.map(|Extension(p)| p).unwrap_or(state.db.clone());
    let token = generate_confirmation_token();

    sqlx::query("UPDATE users SET confirmation_token = $1 WHERE email = $2")
        .bind(&token).bind(&payload.email)
        .execute(&db).await?;

    tracing::info!(email = %payload.email, "Magic link requested (token suppressed)");
    // TODO: Send email with link: {SITE_URL}/auth/confirm?token={token}&type=magiclink

    Ok(Json(serde_json::json!({ "message": "Magic link sent if email exists" })))
}
```

### 3.1.4 DELETE /auth/v1/user

Self-deletion for authenticated users:

```rust
pub async fn delete_user(
    State(state): State<AuthState>,
    db: Option<Extension<PgPool>>,
    Extension(auth_ctx): Extension<AuthContext>,
) -> Result<StatusCode, ApiError> {
    let claims = auth_ctx.claims.ok_or(ApiError::Unauthorized("Not authenticated".into()))?;
    let user_id = Uuid::parse_str(&claims.sub)?;
    let db = db.map(|Extension(p)| p).unwrap_or(state.db.clone());

    // Soft delete: set a deleted_at timestamp
    sqlx::query("UPDATE users SET deleted_at = now() WHERE id = $1")
        .bind(user_id).execute(&db).await?;

    // Revoke all tokens
    sqlx::query("UPDATE refresh_tokens SET revoked = true WHERE user_id = $1")
        .bind(user_id).execute(&db).await?;

    Ok(StatusCode::NO_CONTENT)
}
```

**Migration needed:** `ALTER TABLE users ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;`

---

## 3.2 — Fix Existing Flows

### 3.2.1 Recovery flow must accept new password

**File:** `auth/src/handlers.rs` — `verify` function, recovery branch (line ~335)

```rust
"recovery" => {
    let user = sqlx::query_as::<_, User>(
        "UPDATE users SET recovery_token = NULL WHERE recovery_token = $1 RETURNING *"
    )
    .bind(&payload.token)
    .fetch_optional(&db).await?
    .ok_or(ApiError::BadRequest("Invalid token".into()))?;

    // Apply new password if provided
    if let Some(new_password) = &payload.password {
        let hashed = hash_password(new_password)
            .map_err(|e| ApiError::Internal(e.to_string()))?;
        sqlx::query("UPDATE users SET encrypted_password = $1 WHERE id = $2")
            .bind(&hashed).bind(user.id)
            .execute(&db).await?;
    }

    user
}
```

### 3.2.2 Email change must require re-verification

**File:** `auth/src/handlers.rs` — `update_user` function (line ~392)

Instead of immediately updating the email:

```rust
if let Some(new_email) = &payload.email {
    let token = generate_confirmation_token();
    sqlx::query(
        "UPDATE users SET email_change = $1, email_change_token_new = $2 WHERE id = $3"
    )
    .bind(new_email).bind(&token).bind(user_id)
    .execute(&mut *tx).await?;

    // TODO: Send confirmation email to new_email with token
    tracing::info!(user_id = %user_id, new_email = %new_email, "Email change requested");
}
```

The actual email update happens when the user verifies via `/auth/v1/verify?type=email_change&token=...`.

### 3.2.3 OAuth callback must redirect

**File:** `auth/src/oauth.rs` — `callback` function (end)

```rust
// BEFORE — returns JSON
Ok(Json(AuthResponse { access_token, ... }))

// AFTER — redirect with tokens in fragment
let site_url = std::env::var("SITE_URL").unwrap_or_else(|_| "http://localhost:3000".into());
let redirect_url = format!(
    "{}#access_token={}&token_type=bearer&expires_in={}&refresh_token={}",
    site_url, access_token, expires_in, refresh_token
);
Ok(Redirect::to(&redirect_url))
```

### 3.2.4 MFA verify must issue aal2 token

**File:** `auth/src/mfa.rs` — `verify` function (line ~179)

After successful TOTP verification:

```rust
// Issue upgraded JWT with aal2
let jwt_secret = project_ctx.jwt_secret.as_str();
let (token, expires_in, _) = generate_token_with_aal(
    user_id, &email, "authenticated", jwt_secret, "aal2"
)?;
let refresh_token = issue_refresh_token(&db, user_id, Uuid::new_v4(), None).await
    .map_err(|e| error_response(StatusCode::INTERNAL_SERVER_ERROR, e.1))?;

Ok(Json(serde_json::json!({
    "access_token": token,
    "token_type": "bearer",
    "expires_in": expires_in,
    "refresh_token": refresh_token,
})))
```

**New function needed in `auth/src/utils.rs`:** `generate_token_with_aal()` that adds `aal` and `amr` claims to the JWT.

**Update Claims model** in `auth/src/models.rs`:
```rust
pub struct Claims {
    pub sub: String,
    pub email: Option<String>,
    pub role: String,
    pub exp: usize,
    pub iss: String,
    pub aud: Option<String>,
    pub iat: usize,
    pub session_id: Option<String>,  // NEW
    pub aal: Option<String>,          // NEW: "aal1" or "aal2"
    pub amr: Option<Vec<AmrEntry>>,   // NEW
}

#[derive(Debug, Serialize, Deserialize, Clone)]
pub struct AmrEntry {
    pub method: String,     // "password", "totp", "oauth"
    pub timestamp: usize,
}
```

### 3.2.5 MFA challenge must validate ownership

**File:** `auth/src/mfa.rs` — `challenge` function (line ~186)

```rust
// BEFORE — no user check
let row = sqlx::query("SELECT factor_type FROM auth.mfa_factors WHERE id = $1 AND status = 'verified'")
    .bind(factor_id)...

// AFTER — verify user owns the factor
let user_id = auth_ctx.claims.as_ref()
    .and_then(|c| Uuid::parse_str(&c.sub).ok())
    .ok_or(error_response(StatusCode::UNAUTHORIZED, "Invalid user".into()))?;

let row = sqlx::query("SELECT factor_type FROM auth.mfa_factors WHERE id = $1 AND user_id = $2 AND status = 'verified'")
    .bind(factor_id)
    .bind(user_id)...
```

### 3.2.6 Store and validate MFA challenges

**Migration:**
```sql
CREATE TABLE IF NOT EXISTS auth.mfa_challenges (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    factor_id UUID NOT NULL REFERENCES auth.mfa_factors(id) ON DELETE CASCADE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
    verified_at TIMESTAMPTZ,
    ip_address TEXT
);
CREATE INDEX idx_mfa_challenges_factor ON auth.mfa_challenges(factor_id);
```

In `challenge` handler, insert a challenge row and return its ID. In `verify` handler, validate the challenge_id exists, is recent (< 5 minutes), and belongs to the correct factor.

---

## 3.3 — Session Management

### 3.3.1 Wire in SessionManager

**File:** `auth/src/handlers.rs` — `login` and `signup` functions

After generating tokens, create a session:

```rust
if let Some(session_manager) = &state.session_manager {
    let session_token = session_manager.create_session(
        user.id, user.email.clone(), "authenticated".into()
    ).await.ok();
    // Include session_id in JWT claims (via generate_token)
}
```

**Add to AuthState:**
```rust
pub struct AuthState {
    pub db: PgPool,
    pub config: Config,
    pub session_manager: Option<SessionManager>,
}
```

Initialize in `gateway/src/worker.rs` when Redis is available.

### 3.3.2 Add GET /auth/v1/sessions

List active sessions for "sign out other devices" UI.

---

## 3.4 — Token Quality

### 3.4.1 Configurable token expiry

**File:** `auth/src/utils.rs` — `generate_token` (line 65)

```rust
// BEFORE
Duration::seconds(3600)

// AFTER
let lifetime = std::env::var("ACCESS_TOKEN_LIFETIME")
    .ok()
    .and_then(|v| v.parse::<i64>().ok())
    .unwrap_or(3600);
Duration::seconds(lifetime)
```

### 3.4.2 Hash confirmation/recovery tokens

**File:** `auth/src/handlers.rs` — `signup` function

```rust
let raw_token = generate_confirmation_token();
let hashed_token = hash_refresh_token(&raw_token); // Reuse SHA-256 hasher

// Store hashed version in DB
.bind(&hashed_token)

// Log/email the raw version
tracing::info!("Confirmation token generated for {}", user.email);
```

On verify, hash the incoming token before comparison:
```rust
let hashed_input = hash_refresh_token(&payload.token);
sqlx::query("... WHERE confirmation_token = $1").bind(&hashed_input)
```

---

## Completion Requirements

This milestone is **not complete** until every item below is satisfied.

### 1. Full Test Suite — All Green

- [ ] `cargo test --workspace` passes with **zero failures**
- [ ] All **pre-existing tests** still pass (no regressions)
- [ ] **New unit tests** are written for every feature/fix in this milestone:

| Test | Location | What it validates |
|------|----------|-------------------|
| `test_logout_revokes_refresh_tokens` | `auth/src/handlers.rs` | `POST /logout` sets `revoked = true` on all user refresh tokens |
| `test_logout_returns_204` | `auth/src/handlers.rs` | `POST /logout` returns 204 No Content |
| `test_logout_unauthenticated_401` | `auth/src/handlers.rs` | `POST /logout` without bearer token returns 401 |
| `test_settings_endpoint` | `auth/src/handlers.rs` | `GET /settings` returns provider availability and `autoconfirm` flag |
| `test_magiclink_creates_token` | `auth/src/handlers.rs` | `POST /magiclink` generates a one-time token (DB row exists) |
| `test_recovery_requires_new_password` | `auth/src/handlers.rs` | Verification without `password` in body returns 422 |
| `test_recovery_updates_password` | `auth/src/handlers.rs` | After verification with new password, `password_hash` is updated |
| `test_email_change_requires_verification` | `auth/src/handlers.rs` | `PUT /user` with email change sets `new_email` but doesn't update `email` directly |
| `test_oauth_callback_redirects` | `auth/src/sso.rs` | OAuth callback returns 302 to `SITE_URL` with tokens in fragment |
| `test_mfa_verify_returns_aal2` | `auth/src/mfa.rs` | Successful TOTP verification returns JWT with `aal: aal2` claim |
| `test_mfa_rejects_wrong_factor_owner` | `auth/src/mfa.rs` | Verifying a factor not owned by the user returns 403 |
| `test_token_expiry_configurable` | `auth/src/utils.rs` | JWT `exp` respects `ACCESS_TOKEN_LIFETIME` env var |
| `test_session_list` | `auth/src/session.rs` | `GET /sessions` returns active sessions for the current user |
| `test_confirmation_tokens_hashed` | `auth/src/handlers.rs` | Confirmation token stored in DB is hashed, not plaintext |

### 2. Integration / supabase-js Compatibility Verification

- [ ] `supabase.auth.signOut()` → 204, refresh tokens revoked
- [ ] `supabase.auth.getSession()` returns null after signOut
- [ ] Password recovery flow: request → verify with new password → login with new password works
- [ ] Email change: request → confirmation email sent → verify → email updated
- [ ] OAuth callback redirects to `SITE_URL` with tokens in fragment
- [ ] MFA enroll → challenge → verify returns aal2 token
- [ ] MFA challenge rejects if user doesn't own the factor
- [ ] Token expiry respects `ACCESS_TOKEN_LIFETIME` env var
- [ ] `GET /auth/v1/settings` returns correct provider availability
- [ ] `supabase.auth.signUp()` / `signInWithPassword()` / `signInWithOAuth()` / `resetPasswordForEmail()` / `updateUser()` — all return shapes match supabase-js expectations

### 3. CI Gate

- [ ] All unit tests run in `cargo test --workspace`
- [ ] Tests that require a running Postgres are either:
  - (a) using an in-memory SQLx test database, or
  - (b) gated behind `#[ignore]` with a comment explaining the external dependency
- [ ] No `#[allow(unused)]` on any new code in this milestone