Sessions

Session endpoints manage authentication — login, mid-login challenge resume, token refresh, and logout.

Login

API

POST /gatelin/sessions
Content-Type: application/json

{
  "email": "user@example.com",
  "pwd": "password"
}

Response (200 OK) — password accepted and no mid-login challenge required:

{
  "nickname": "jane",
  "accessToken": "eyJhbGc...",
  "roles": [1, 2],
  "permissions": [
    { "route": 4, "operations": [1, 2], "fields": [], "scopes": [] }
  ]
}

A CSRF cookie (csrfToken by default) is also set. When REFRESH_TOKEN_COOKIE is enabled, the refresh token is stored as an httpOnly cookie (and omitted from the JSON body when marked private).

Response (202 Accepted) — password accepted, but a mid-login challenge must be completed first:

{
  "challengeRequired": true,
  "kind": "2fa",
  "url": "https://example.com/api/pwd/web/2fa/verify?challenge=…"
}

kind	When it is returned
expired-password	The account's password has expired
2fa	Two-factor is enabled and the browser has no valid trusted-device cookie

The client must send the browser to url. That URL is served entirely by your password service — Gatelin does not render or control it. When the workflow finishes, your service redirects the browser back to the admin login with ?ticket=…, and the frontend calls Resume to create the session.

Other error statuses:

Status	Meaning
400	Missing or invalid email / pwd
401	Wrong credentials
403	Account locked
404	User not found

Password-service contract

Gatelin never stores password hashes or 2FA secrets, and never renders challenge pages. It delegates all of that to a password service you point PWD_CHECK_URL at. Any service that speaks the small HTTP contract below works.

Credential check (required)

PWD_CHECK_URL is the only endpoint Gatelin always calls. On a correct password it must return HTTP 200 with a single user row:

{
  "rows": [{
    "userId": 42,
    "pwdExpiry": null,
    "lockedUntil": null,
    "twoFactorEnabled": false
  }],
  "total": 1
}

On a wrong password it must return a non-2xx status (typically 401).

Gatelin reads only these fields from rows[0]; any others are ignored:

Field	Type	Effect on login
lockedUntil	ISO date string or null	If in the future, login is rejected with 403
pwdExpiry	ISO date string or null	If in the past, login returns 202 expired-password
twoFactorEnabled	boolean	If true (and no trusted-device cookie), login returns 202 2fa

Don't need challenges? If your service only checks passwords, return a body without a rows entry (for example { "success": true }, or { "rows": [], "total": 0 }). Gatelin then treats the login as fully authenticated, skips all gating, and logs a debug/warn note. This is the correct setup for a plain username+password login with no 2FA or password-expiry policy.

Challenge endpoints (only if you emit 202)

If your credential check can return pwdExpiry, lockedUntil, or twoFactorEnabled, then Gatelin also needs the endpoints below. Each one has its own environment variable — nothing is derived from PWD_CHECK_URL, so you are free to name and place these routes however you like:

Variable	Request body	Expected response	Called when
PWD_CHALLENGES_URL	{ userId, kind }	{ url, kind } — url is the browser page that runs the challenge	A challenge is required
PWD_TRUSTED_DEVICES_URL	{ userId, deviceToken }	{ trusted: boolean }	2FA is enabled and a trusted-device cookie is present
PWD_LOGIN_TICKET_URL	{ ticket }	{ userId }	The frontend calls Resume

All three are POST endpoints and all three may be empty. Gatelin still boots and password login still succeeds. Empty PWD_CHALLENGES_URL skips 2FA and password-expiry pages (a warn is logged). Empty PWD_TRUSTED_DEVICES_URL ignores the trusted-device cookie. Empty PWD_LOGIN_TICKET_URL makes Resume answer 501.

Trusted-device cookie

To let a returning browser skip 2FA, your challenge pages may set a trusted-device cookie named trusted_device (scoped Path=/ so it reaches /gatelin/sessions). On the next login Gatelin forwards its value to PWD_TRUSTED_DEVICES_URL; a { trusted: true } response suppresses the 2FA challenge. If you don't implement trusted devices, simply never set the cookie — every 2FA login then challenges.

Sequence diagram

Resume

Finishes a login that was interrupted by a mid-login challenge. Public — no JWT required.

POST /gatelin/sessions/resume
Content-Type: application/json

{
  "ticket": "one-shot-login-resume-ticket"
}

Gatelin redeems the ticket against the password service (POST PWD_LOGIN_TICKET_URL), looks the user up by id, then runs the same token / session / CSRF path as a successful login.

Response (200 OK): same session payload as Login.

Status	Meaning
400	Missing, invalid, or already-consumed ticket
422	Ticket redeemed but the user lookup failed

Tickets are one-shot and short-lived. The admin UI reads ?ticket= on the login page and calls this endpoint automatically.

Refresh Tokens

PUT /gatelin/sessions
Content-Type: application/json
Authorization: Bearer <access_token>
X-CSRF-Token: <csrf_cookie_value>
Cookie: csrfToken=<csrf_cookie_value>; refreshToken=<optional>

{
  "refreshToken": "eyJhbGc..."
}

The access token may already be expired — refresh ignores expiration after CSRF and refresh-token checks pass. The refresh token may be supplied in the JSON body and/or the refresh-token cookie.

Response (200 OK):

{
  "nickname": "jane",
  "accessToken": "new_access_token",
  "refreshToken": "new_refresh_token",
  "roles": [1, 2],
  "permissions": [
    { "route": 4, "operations": [1, 2], "fields": [], "scopes": [] }
  ]
}

A fresh CSRF cookie is issued with the new tokens.

Logout

DELETE /gatelin/sessions
Authorization: Bearer <access_token>
X-CSRF-Token: <csrf_cookie_value>
Cookie: csrfToken=<csrf_cookie_value>

Response (204 No Content)

The consumer session is archived, removed from the cache, and refresh/CSRF cookies are cleared.