Fix various MyPy issues in airflow/www folder (part 1) (#20120)

airflow/www/extensions/init_appbuilder.py

@@ -22,10 +22,10 @@
 
 import logging
 from functools import reduce
-from typing import Dict
+from typing import Dict, List, Union
 
 from flask import Blueprint, current_app, url_for
-from flask_appbuilder import __version__
+from flask_appbuilder import BaseView, __version__
 from flask_appbuilder.api.manager import OpenApiManager
 from flask_appbuilder.babel.manager import BabelManager
 from flask_appbuilder.const import (
@@ -39,7 +39,9 @@
 )
 from flask_appbuilder.filters import TemplateFilters
 from flask_appbuilder.menu import Menu, MenuApiManager
+from flask_appbuilder.security.manager import BaseSecurityManager
 from flask_appbuilder.views import IndexView, UtilView
+from sqlalchemy.orm import Session
 
 from airflow import settings
 from airflow.configuration import conf
@@ -90,14 +92,14 @@ class AirflowAppBuilder:
     You can also create everything as an application factory.
     """
 
-    baseviews = []
+    baseviews: List[Union[BaseView, Session]] = []
     security_manager_class = None
     # Flask app
     app = None
     # Database Session
     session = None
     # Security Manager Class
-    sm = None
+    sm: BaseSecurityManager
     # Babel Manager Class
     bm = None
     # OpenAPI Manager Class

airflow/www/utils.py

@@ -331,11 +331,10 @@ def datetime_html(dttm: Optional[DateTime]) -> str:
     as_iso = dttm.isoformat() if dttm else ''
     if not as_iso:
         return Markup('')
-    dttm = as_iso
-    if timezone.utcnow().isoformat()[:4] == dttm[:4]:
-        dttm = dttm[5:]
+    if timezone.utcnow().isoformat()[:4] == as_iso[:4]:
+        as_iso = as_iso[5:]
     # The empty title will be replaced in JS code when non-UTC dates are displayed
-    return Markup('<nobr><time title="" datetime="{}">{}</time></nobr>').format(as_iso, dttm)
+    return Markup('<nobr><time title="" datetime="{}">{}</time></nobr>').format(as_iso, as_iso)
 
 
 def json_f(attr_name):