midjourney-auth

Authentication (MidjourneyAuth)

Module: midjourney_api.auth

Setup (.env)

MJ_REFRESH_TOKEN=your_firebase_refresh_token

The refresh token is a Firebase Auth token obtained via browser OAuth login.

MidjourneyAuth Class

from midjourney_api.auth import MidjourneyAuth

# Load from .env (default)
auth = MidjourneyAuth()

# Or provide directly
auth = MidjourneyAuth(refresh_token="AMf-vBw...")

# Custom .env path
auth = MidjourneyAuth(env_path="/path/to/.env")

Constructor

MidjourneyAuth(
    refresh_token: str | None = None,  # explicit token (overrides .env)
    env_path: str = ".env",            # path to .env file
)

On init:

1. Loads .env via python-dotenv
2. Reads MJ_REFRESH_TOKEN (unless explicit token provided)
3. If valid token exists, immediately calls _do_refresh() to get an ID token

Token Lifecycle

Automatic Refresh

auth.ensure_valid_token()

• Called automatically before every API request
• Checks time.time() >= token_expiry - 60 (60-second buffer)
• If expired/expiring → exchanges refresh token via Firebase REST API
• Gets new id_token + refresh_token + expires_in

Firebase Token Exchange

POST https://securetoken.googleapis.com/v1/token?key=<FIREBASE_API_KEY>
Content-Type: application/x-www-form-urlencoded

grant_type=refresh_token&refresh_token=<refresh_token>

Response:

{
  "id_token": "eyJhbGci...",
  "refresh_token": "AMf-vBw...",
  "expires_in": "3600"
}

User ID Extraction

• Parses JWT payload from id_token
• Extracts midjourney_id field → used as user_id for all API calls

Cookie Header

cookie_str = auth.cookie_header()
# → "__Host-Midjourney.AuthUserTokenV3_i=<id_token>; __Host-Midjourney.AuthUserTokenV3_r=<refresh_token>"

All API requests require this cookie header.

Properties

Property	Type	Description
auth.user_id	str	Midjourney user ID (from JWT). Raises AuthenticationError if not authenticated
auth.id_token	str	Current ID token (auto-refreshes if expired)

Browser Login

auth = MidjourneyAuth()
auth.login()  # Opens Chromium browser for Google OAuth

1. Launches persistent Chromium context via Playwright
2. Navigates to https://www.midjourney.com/
3. Polls cookies for __Host-Midjourney.AuthUserTokenV3_r
4. Extracts refresh token → exchanges for ID token
5. Saves to .env as MJ_REFRESH_TOKEN=...

Requires: playwright install chromium (playwright is a core dependency)

Using with MidjourneyClient

MidjourneyClient manages auth internally:

# Auth is automatic — just set MJ_REFRESH_TOKEN in .env
with MidjourneyClient() as client:
    job = client.imagine("hello world")

# Or login via client
client = MidjourneyClient()
client.login()  # opens browser

Using with MidjourneyAPI (Low-Level)

from midjourney_api.auth import MidjourneyAuth
from midjourney_api.api import MidjourneyAPI

auth = MidjourneyAuth()
api = MidjourneyAPI(auth)
# auth.ensure_valid_token() is called automatically by api._request()

Exceptions

Exception	When
AuthenticationError("Not authenticated...")	user_id accessed before login/refresh
AuthenticationError("No refresh token...")	ensure_valid_token() with no token
AuthenticationError("Token refresh failed...")	Firebase API returns HTTP error
AuthenticationError("midjourney_id not found...")	JWT missing midjourney_id field