FlaskGroup Class — flask Architecture

Architecture documentation for the FlaskGroup class in cli.py from the flask codebase.

Class python ApplicationCore

Entity Profile

ApplicationCore→ FlaskGroup Class — flask Architecture

Dependency Diagram

graph TD
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b["FlaskGroup"]
  ea63e19e_2fd3_885d_2922_e4101fe8320a["AppGroup"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|extends| ea63e19e_2fd3_885d_2922_e4101fe8320a
  9fb0ba66_32bf_1412_77b1_174dae79c4b2["ScriptInfo"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|extends| 9fb0ba66_32bf_1412_77b1_174dae79c4b2
  a96499c3_f8a9_e782_f156_1c1ee4a86c69["cli.py"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|defined in| a96499c3_f8a9_e782_f156_1c1ee4a86c69
  e9361747_7510_50a9_29c5_1934b7b46b16["__init__()"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|method| e9361747_7510_50a9_29c5_1934b7b46b16
  67dea11c_5c94_6773_8a63_f280d0830338["_load_plugin_commands()"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|method| 67dea11c_5c94_6773_8a63_f280d0830338
  596bd738_9f64_52c9_9cdc_d6c4ce8f6278["get_command()"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|method| 596bd738_9f64_52c9_9cdc_d6c4ce8f6278
  d828f6fc_89be_5a05_5589_42611ae7786a["list_commands()"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|method| d828f6fc_89be_5a05_5589_42611ae7786a
  57df2c73_65cb_ce7f_551b_d57f6d93eddf["make_context()"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|method| 57df2c73_65cb_ce7f_551b_d57f6d93eddf
  e15a2edb_266e_9bc5_e178_cc73b9ab503d["parse_args()"]
  ee9fbc8f_42bd_3ef5_a80f_72abfe054c0b -->|method| e15a2edb_266e_9bc5_e178_cc73b9ab503d

Relationship Graph

Source Code

src/flask/cli.py lines 531–688

class FlaskGroup(AppGroup):
    """Special subclass of the :class:`AppGroup` group that supports
    loading more commands from the configured Flask app.  Normally a
    developer does not have to interface with this class but there are
    some very advanced use cases for which it makes sense to create an
    instance of this. see :ref:`custom-scripts`.

    :param add_default_commands: if this is True then the default run and
        shell commands will be added.
    :param add_version_option: adds the ``--version`` option.
    :param create_app: an optional callback that is passed the script info and
        returns the loaded app.
    :param load_dotenv: Load the nearest :file:`.env` and :file:`.flaskenv`
        files to set environment variables. Will also change the working
        directory to the directory containing the first file found.
    :param set_debug_flag: Set the app's debug flag.

    .. versionchanged:: 3.1
        ``-e path`` takes precedence over default ``.env`` and ``.flaskenv`` files.

    .. versionchanged:: 2.2
        Added the ``-A/--app``, ``--debug/--no-debug``, ``-e/--env-file`` options.

    .. versionchanged:: 2.2
        An app context is pushed when running ``app.cli`` commands, so
        ``@with_appcontext`` is no longer required for those commands.

    .. versionchanged:: 1.0
        If installed, python-dotenv will be used to load environment variables
        from :file:`.env` and :file:`.flaskenv` files.
    """

    def __init__(
        self,
        add_default_commands: bool = True,
        create_app: t.Callable[..., Flask] | None = None,
        add_version_option: bool = True,
        load_dotenv: bool = True,
        set_debug_flag: bool = True,
        **extra: t.Any,
    ) -> None:
        params: list[click.Parameter] = list(extra.pop("params", None) or ())
        # Processing is done with option callbacks instead of a group
        # callback. This allows users to make a custom group callback
        # without losing the behavior. --env-file must come first so
        # that it is eagerly evaluated before --app.
        params.extend((_env_file_option, _app_option, _debug_option))

        if add_version_option:
            params.append(version_option)

        if "context_settings" not in extra:
            extra["context_settings"] = {}

        extra["context_settings"].setdefault("auto_envvar_prefix", "FLASK")

        super().__init__(params=params, **extra)

        self.create_app = create_app
        self.load_dotenv = load_dotenv
        self.set_debug_flag = set_debug_flag

        if add_default_commands:
            self.add_command(run_command)
            self.add_command(shell_command)
            self.add_command(routes_command)

        self._loaded_plugin_commands = False

    def _load_plugin_commands(self) -> None:
        if self._loaded_plugin_commands:
            return

        for ep in importlib.metadata.entry_points(group="flask.commands"):
            self.add_command(ep.load(), ep.name)

        self._loaded_plugin_commands = True

    def get_command(self, ctx: click.Context, name: str) -> click.Command | None:
        self._load_plugin_commands()
        # Look up built-in and plugin commands, which should be