Comfy-Org/ComfyUI · error · ValueError

Unsupported database URL '{url}'.

Error message

Unsupported database URL '{url}'.

What it means

Raised by get_db_path() when args.database_url does not start with 'sqlite:///'. This ComfyUI-asset server's database layer only supports SQLite, and the URL convention is fixed: everything after 'sqlite:///' is taken as the file path. Any other scheme (postgres://, mysql://, or a bare path) is rejected upfront.

Source

Thrown at app/database/db.py:70

def get_alembic_config():
    root_path = os.path.join(os.path.dirname(__file__), "../..")
    config_path = os.path.abspath(os.path.join(root_path, "alembic.ini"))
    scripts_path = os.path.abspath(os.path.join(root_path, "alembic_db"))

    config = Config(config_path)
    config.set_main_option("script_location", scripts_path)
    config.set_main_option("sqlalchemy.url", args.database_url)

    return config


def get_db_path():
    url = args.database_url
    if url.startswith("sqlite:///"):
        return url.split("///")[1]
    else:
        raise ValueError(f"Unsupported database URL '{url}'.")


_db_lock = None

def _acquire_file_lock(db_path):
    """Acquire an OS-level file lock to prevent multi-process access.

    Uses filelock for cross-platform support (macOS, Linux, Windows).
    The OS automatically releases the lock when the process exits, even on crashes.
    """
    global _db_lock
    lock_path = db_path + ".lock"
    _db_lock = FileLock(lock_path)
    try:
        _db_lock.acquire(timeout=0)
    except Timeout:
        raise RuntimeError(
            f"Could not acquire lock on database '{db_path}'. "

View on GitHub (pinned to 1c6d8d45b3)

Solutions

1. Use a SQLite URL: --database-url sqlite:///absolute/or/relative/path.db (three slashes then the path).
2. If you actually need a network database, this build does not support it — remove the env override and use the default SQLite location, or patch the layer yourself.
3. In Docker/CI, set DATABASE_URL='sqlite:////data/assets.db' (four slashes for absolute path) and ensure the directory exists and is writable.

Example fix

# before
DATABASE_URL=postgres://user:pass@db/assets

# after
DATABASE_URL=sqlite:////data/assets.db

import re
SQLITE_URL = re.compile(r'^sqlite:///\S.*$')

def usable_db_url(url: str) -> bool:
    return bool(SQLITE_URL.match(url))

def is_sqlite_url(url: str) -> bool:
    return isinstance(url, str) and url.startswith('sqlite:///')

try:
    db_path = get_db_path()
except ValueError as e:
    raise SystemExit(f'bad --database-url: {e}') from e

When it happens

Trigger: Launching the server with --database-url postgresql://... or DATABASE_URL=mysql://...; or passing a bare relative path like 'data.db' without the sqlite:/// prefix; or 'sqlite:///' vs 'sqlite://' (two slashes = empty host, still fails the startswith check only if not matching exactly).

Common situations: Reusing a DATABASE_URL from another service that runs Postgres/MySQL; CI env vars carrying a generic connection string; docs/examples that show bare paths; porting expectations from an ORM stack that accepts many schemes.

Related errors

• Could not acquire lock on database '{db_path}'. Another Comf
• ASSET_NOT_FOUND
• INVALID_BODY
• ASSET_NOT_FOUND
• no base path configured for category '{folder_name}'

AI-assisted analysis of Comfy-Org/ComfyUI@1c6d8d45b3 (2026-08-14). Data as JSON: /api/errors/ee45ced514275bb5. Report an issue: GitHub.