reflex-dev/reflex · error · SystemExit

Only {template_name=} should be provided, got {template_code

Error message

Only {template_name=} should be provided, got {template_code_dir_name=}, {template_dir=}.

What it means

Raised by `reflex.utils.templates.initialize_app_directory` when the default template is selected but extra template location arguments are also supplied. The DEFAULT template is bundled in local Reflex assets, so template_code_dir_name/template_dir are hard-coded internally; providing them indicates the caller misunderstood the API.

Source

Thrown at reflex/utils/templates.py:66

    Args:
        app_name: The name of the app.
        template_name: The name of the template to use.
        template_code_dir_name: The name of the code directory in the template.
        template_dir: The directory of the template source files.

    Raises:
        SystemExit: If template_name, template_code_dir_name, template_dir combination is not supported.
    """
    logger.info("Initializing the app directory.")

    # By default, use the blank template from local assets.
    if template_name == constants.Templates.DEFAULT:
        if template_code_dir_name is not None or template_dir is not None:
            logger.error(
                f"Only {template_name=} should be provided, got {template_code_dir_name=}, {template_dir=}."
            )
            raise SystemExit(1)
        template_code_dir_name = constants.Templates.Dirs.CODE
        template_dir = Path(constants.Templates.Dirs.BASE, "apps", template_name)
    else:
        if template_code_dir_name is None or template_dir is None:
            logger.error(
                f"For `{template_name}` template, `template_code_dir_name` and `template_dir` should both be provided."
            )
            raise SystemExit(1)

    logger.debug(f"Using {template_name=} {template_dir=} {template_code_dir_name=}.")

    # Remove __pycache__ dirs in template directory and current directory.
    for pycache_dir in [
        *template_dir.glob("**/__pycache__"),
        *Path.cwd().glob("**/__pycache__"),
    ]:
        shutil.rmtree(pycache_dir, ignore_errors=True)

View on GitHub (pinned to 45b8ed5ab7)

Solutions

1. Drop template_code_dir_name and template_dir arguments when using the default template; Reflex fills them from bundled assets.
2. If you intended a custom/remote template, pass a non-default template_name along with both template_code_dir_name and template_dir.

Example fix

# before
initialize_app_directory(
    template_name=constants.Templates.DEFAULT,
    template_dir=Path("./my_template"),
    template_code_dir_name="code",
)

# after
initialize_app_directory(template_name=constants.Templates.DEFAULT)

from reflex import constants

def validate_template_args(name, code_dir_name, template_dir):
    if name == constants.Templates.DEFAULT:
        assert code_dir_name is None and template_dir is None
    else:
        assert code_dir_name is not None and template_dir is not None

When it happens

Trigger: Calling initialize_app_directory(template_name=constants.Templates.DEFAULT ('default'), ...) with a non-None template_code_dir_name or template_dir. Typically reached via initialize_default_app or create_config_init_app_from_remote_template wiring arguments incorrectly.

Common situations: Custom scaffolding code that always passes template_dir regardless of template name; copy-pasted calls from remote-template code paths into default-template paths.

Related errors

• For `{template_name}` template, `template_code_dir_name` and
• Only one of `data` or `fp` may be provided, not both.
• At least one of `data` or `fp` must be provided.
• Cannot use --single-port with --frontend-only or --backend-o
• Failed to create temp directory for download: {ose}

AI-assisted analysis of reflex-dev/reflex@45b8ed5ab7 (2026-08-28). Data as JSON: /api/errors/3946c584d6c0f4d1. Report an issue: GitHub.