Make warnings more visible (apache#12204)

This PR proposes to use custom showwarning function that
provides users with better information about warnings using
rich library to highlight the warning.

LICENSE

@@ -240,6 +240,7 @@ The text of each license is also included at licenses/LICENSE-[project].txt.
     (MIT License) moment-strftime v0.5.0 (https://github.com/benjaminoakes/moment-strftime)
     (MIT License) python-slugify v4.0.0 (https://github.com/un33k/python-slugify)
     (MIT License) python-nvd3 v0.15.0 (https://github.com/areski/python-nvd3)
+    (MIT License) rich v9.2.0 (https://github.com/willmcgugan/rich)
     (MIT License) eonasdan-bootstrap-datetimepicker v4.17.37 (https://github.com/eonasdan/bootstrap-datetimepicker/)
 
 ========================================================================

airflow/settings.py

@@ -20,9 +20,11 @@
 import logging
 import os
 import sys
+import warnings
 from typing import Optional
 
 import pendulum
+import rich
 from sqlalchemy import create_engine, exc
 from sqlalchemy.engine import Engine
 from sqlalchemy.orm import scoped_session, sessionmaker
@@ -94,6 +96,17 @@
 }
 
 
+def custom_show_warning(message, category, filename, lineno, file=None, line=None):
+    """Custom function to print rich and visible warnings"""
+    msg = f"[bold]{line}" if line else f"[bold][yellow]{filename}:{lineno}"
+    msg += f" {category.__name__}[/bold]: {message}[/yellow]"
+    file = file or sys.stderr
+    rich.print(msg, file=file)
+
+
+warnings.showwarning = custom_show_warning
+
+
 def policy(task):  # pylint: disable=unused-argument
     """
     This policy setting allows altering tasks after they are loaded in

setup.py

@@ -743,6 +743,7 @@ def is_package_excluded(package: str, exclusion_list: List[str]):
     'python-nvd3~=0.15.0',
     'python-slugify>=3.0.0,<5.0',
     'requests>=2.20.0, <3',
+    'rich==9.2.0',
     'setproctitle>=1.1.8, <2',
     'sqlalchemy>=1.3.18, <2',
     'sqlalchemy_jsonfield~=0.9',