Remove global statement from Fab provider

Author: jscheffl

providers/fab/src/airflow/providers/fab/www/app.py

@@ -18,6 +18,7 @@
 from __future__ import annotations
 
 from datetime import timedelta
+from functools import cache
 from os.path import isabs
 
 from flask import Flask
@@ -44,8 +45,6 @@
 from airflow.providers.fab.www.extensions.init_wsgi_middlewares import init_wsgi_middleware
 from airflow.providers.fab.www.utils import get_session_lifetime_config
 
-app: Flask | None = None
-
 # Initializes at the module level, so plugins can access it.
 # See: /docs/plugins.rst
 csrf = CSRFProtect()
@@ -119,15 +118,12 @@ def create_app(enable_plugins: bool):
     return flask_app
 
 
+@cache
 def cached_app():
     """Return cached instance of Airflow WWW app."""
-    global app
-    if not app:
-        app = create_app()
-    return app
+    return create_app()
 
 
 def purge_cached_app():
     """Remove the cached version of the app in global state."""
-    global app
-    app = None
+    cached_app.cache_clear()

providers/fab/www-hash.txt

@@ -1 +1 @@
-48926a5d09f218deb70a461d36aecec7e883a2210dea809082c99dbf0bd8d77d
+9a7fd1175fa3e57b636662428771b3c9586be5551fe96e8dc35afffd792229d1