Merge pull request #3 from oxsecurity/add-option-to-partial-mask

Add option to partial mask

README.md

@@ -49,15 +49,24 @@ from masker_formatter import MaskerFormatter, SKIP_MASK
 logger.info('Line you want to skip', extra=SKIP_MASK)
 ```
 
-#### fix len masking
-If you want the masking to be in a fixed size (and not in the secret len),  
-please set the `fix_masking_len`:  
+#### redact
+Here’s a rewritten version suitable for inclusion in a README.md file:
+
+---
+
+### Partial Masking of Secrets
+If you prefer to mask only a portion of a secret (rather than its entire length), you can set the `redact` parameter in the formatter. The `redact` parameter specifies the percentage of the secret to be masked.
+
+Here’s an example of how to use it:
+
 ```
 handler.setFormatter(
     MaskerFormatter("%(asctime)s %(name)s %(levelname)s %(message)s",
-                    fix_masking_len=30))
+                    redact=30))
 ```
 
+In this example, 30% of the secret will be masked. Adjust the `redact` value as needed to suit your requirements.
+
 ## The Config File
 
 Here's where the magic happens!  

maskerlogger/masker_formatter.py

@@ -14,12 +14,17 @@ class MaskerFormatter(logging.Formatter):
     def __init__(self, fmt=None, datefmt=None, style='%', validate=True,
                  defaults=None,
                  regex_config_path=DEFAULT_SECRETS_CONFIG_PATH,
-                 fix_masking_len=-1):
+                 redact=100):
         super().__init__(fmt, datefmt, style, validate=validate,
                          defaults=defaults)
-        self.fix_masking_len = fix_masking_len
+        self.redact = self._validate_redact(redact)
         self.regex_matcher = RegexMatcher(regex_config_path)
 
+    def _validate_redact(self, redact: int) -> int:
+        if not (0 <= int(redact) <= 100):
+            raise ValueError("Redact value must be between 0 and 100")
+        return int(redact)
+
     def format(self, record: logging.LogRecord) -> str:
         if getattr(record, _APPLY_MASK, True):
             self._mask_sensitive_data(record)
@@ -29,8 +34,9 @@ def _mask_secret(self, msg: str, matches: List[re.Match]) -> str:
         for match in matches:
             match_groups = match.groups() if match.groups() else [match.group()]  # noqa
             for group in match_groups:
-                replace_len = len(group) if self.fix_masking_len < 0 else self.fix_masking_len # noqa
-                msg = msg.replace(group, "*" * replace_len)
+                redact_length = int((len(group) / 100) * self.redact)
+                msg = msg.replace(
+                    group[:redact_length], "*" * redact_length, 1)
             return msg
 
     def _mask_sensitive_data(self, record: logging.LogRecord) -> None:

maskerlogger/secrets_in_logs_example.py

@@ -15,7 +15,7 @@ def main():
     handler = logging.StreamHandler()
     handler.setFormatter(
         MaskerFormatter("%(asctime)s %(name)s %(levelname)s %(message)s",
-                        fix_masking_len=30))
+                        redact=50))
     logger.addHandler(handler)
 
     logger.info('"current_key": "AIzaSOHbouG6DDa6DOcRGEgOMayAXYXcw6la3c"', extra=SKIP_MASK) # noqa