Adds logger filter for TOKENS when logging in DEBUG MODE

AUTHORS.rst

@@ -25,3 +25,5 @@ Maintainers & Contributors
 - Sylvain Marie <[email protected]>
 - Craig Anderson <[email protected]>
 - Hugo van Kemenade <https://github.com/hugovk>
+- Jacques Troussard <https://github.com/jtroussard>
+- Erland Vollset <https://github.com/erlendvollset>

README.rst

@@ -56,3 +56,22 @@ To install requests and requests_oauthlib you can use pip:
  :alt: Documentation Status
  :scale: 100%
  :target: https://requests-oauthlib.readthedocs.io/
+
+Advanced Configurations
+-----------------------
+
+### Logger Configuration Framework
+
+`requests-oauthlib` now includes a flexible framework for applying custom filters and configurations to the logger, enhancing control over logging behavior and improving security.
+
+#### Custom Filters
+
+- **Debug Mode Token Filter**: To enhance security and provide more control over logging of sensitive information, requests-oauthlib introduces the Debug Mode Token Filter. This feature is controlled via the DEBUG_MODE_TOKEN_FILTER environment variable, allowing the suppression or masking of sensitive data in logs.
+
+ ##### Configuring the Debug Mode Token Filter
+
+ - **Environment Variable**: `DEBUG_MODE_TOKEN_FILTER`
+ - **Options**:
+ - `DEFAULT`: No alteration to logging behavior.
+ - `MASK`: Masks sensitive tokens in logs.
+ - `SUPPRESS`: Prevents logging of potentially sensitive information. (logger ignores these logs entirely)

requests_oauthlib/__init__.py

@@ -6,6 +6,8 @@
 from .oauth2_auth import OAuth2
 from .oauth2_session import OAuth2Session, TokenUpdated
 
+from .log_filters import DebugModeTokenFilter
+
 __version__ = "2.0.0"
 
 import requests
@@ -18,3 +20,11 @@
  raise Warning(msg % requests.__version__)
 
 logging.getLogger("requests_oauthlib").addHandler(logging.NullHandler())
+logging.getLogger("requests_oauthlib").addFilter(DebugModeTokenFilter())
+
+for filter_ in logging.getLogger("requests_oauthlib").filters:
+ if isinstance(filter_, DebugModeTokenFilter):
+ if filter_.mode == 'DEFAULT':
+ msg = "Your logger, when in DEBUG mode, will log TOKENS"
+ logging.warning(msg)
+ break 

requests_oauthlib/log_filters.py

@@ -0,0 +1,40 @@
+import os
+import re
+import logging
+
+class DebugModeTokenFilter(logging.Filter):
+ """
+ A logging filter that while in DEBUG mode can filter TOKENS dependent on configuration.
+
+ This filter uses an environment variable to determine its mode, 
+ which can either mask sensitive tokens in log messages, suppress logging, 
+ or default to standard logging behavior with a warning.
+
+ Attributes:
+ mode (str): The mode of operation based on the environment variable
+ 'DEBUG_MODE_TOKEN_FILTER'. Can be 'MASK', 'SUPPRESS', or 'DEFAULT'.
+ """
+ def __init__(self):
+ """
+ Initializes the DebugModeTokenFilter with the 'DEBUG_MODE_TOKEN_FILTER'
+ environment variable.
+ """
+ super().__init__()
+ self.mode = os.getenv('DEBUG_MODE_TOKEN_FILTER', 'DEFAULT').upper()
+
+ def filter(self, record):
+ """
+ Filters logs of TOKENS dependent on the configured mode.
+
+ Args:
+ record (logging.LogRecord): The log record to filter.
+
+ Returns:
+ bool: True if the record should be logged, False otherwise.
+ """
+ if record.levelno == logging.DEBUG:
+ if self.mode == "MASK":
+ record.msg = re.sub(r'Bearer\s+([A-Za-z0-9\-._~+\/]+)', '[MASKED]', record.getMessage())
+ elif self.mode == "SUPPRESS":
+ return False
+ return True # if mode is not MASKED then DEFAULT is implied 

tests/test_log_filters.py

@@ -0,0 +1,30 @@
+import unittest
+from unittest.mock import patch
+import logging
+from requests_oauthlib.log_filters import DebugModeTokenFilter
+
+class TestDebugModeTokenFilter(unittest.TestCase):
+
+ def setUp(self):
+ self.record = logging.LogRecord(name="test", level=logging.DEBUG, pathname=None, lineno=None, msg="Bearer i-am-a-little-token-here-is-my-scope-and-here-is-my-signature", args=None, exc_info=None)
+
+ @patch.dict('os.environ', {'DEBUG_MODE_TOKEN_FILTER': 'MASK'})
+ def test_mask_mode(self):
+ filter = DebugModeTokenFilter()
+ filter.filter(self.record)
+ self.assertIn('[MASKED]', self.record.msg)
+
+ @patch.dict('os.environ', {'DEBUG_MODE_TOKEN_FILTER': 'SUPPRESS'})
+ def test_suppress_mode(self):
+ filter = DebugModeTokenFilter()
+ result = filter.filter(self.record)
+ self.assertFalse(result) # No logging
+
+ @patch.dict('os.environ', {'DEBUG_MODE_TOKEN_FILTER': 'DEFAULT'})
+ def test_default_mode_raises_warning(self):
+ filter = DebugModeTokenFilter()
+ result = filter.filter(self.record)
+ self.assertTrue(result)
+
+if __name__ == '__main__':
+ unittest.main()