airflow/utils/cli_app_builder.py

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# to you under the Apache License, Version 2.0 (the
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#
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from __future__ import annotations

import os
from contextlib import contextmanager
from functools import lru_cache
from typing import Generator

from flask import Flask

import airflow
from airflow.www.extensions.init_appbuilder import AirflowAppBuilder, init_appbuilder
from airflow.www.extensions.init_views import init_plugins


@lru_cache(maxsize=None)
def _return_appbuilder(app: Flask) -> AirflowAppBuilder:
    """Returns an appbuilder instance for the given app."""
    init_appbuilder(app)
    init_plugins(app)
    return app.appbuilder  # type: ignore[attr-defined]


@contextmanager
def get_application_builder() -> Generator[AirflowAppBuilder, None, None]:
    static_folder = os.path.join(os.path.dirname(airflow.__file__), "www", "static")
    flask_app = Flask(__name__, static_folder=static_folder)
    with flask_app.app_context():
        yield _return_appbuilder(flask_app)