fix(_logging.py): add sensitive data filter to logging

Fixes https://github.com/BerriAI/litellm/issues/7603

Also addresses https://github.com/BerriAI/litellm/issues/9815#issuecomment-2806844725

tests/litellm/test_logging.py

@@ -0,0 +1,99 @@
+import logging
+
+import pytest
+
+from litellm._logging import SensitiveDataFilter
+
+
+def test_sensitive_data_filter():
+    # Create a test logger
+    logger = logging.getLogger("test_logger")
+    logger.setLevel(logging.INFO)
+
+    # Create a filter
+    sensitive_filter = SensitiveDataFilter()
+
+    # Test cases
+    test_cases = [
+        {
+            "input": '{"vertex_credentials": {"project_id": "test-project", "location": "us-central1", "private_key": "test-private-key"}}',
+            "expected": '{"vertex_credentials": {"project_id": "test-project", "location": "us-central1", "private_key": "REDACTED"}}',
+        },
+        {
+            "input": '{"api_key": "sk-1234567890"}',
+            "expected": '{"api_key": "REDACTED"}',
+        },
+        {
+            "input": '{"openai_api_key": "sk-1234567890"}',
+            "expected": '{"openai_api_key": "REDACTED"}',
+        },
+        {"input": '{"password": "secret123"}', "expected": '{"password": "REDACTED"}'},
+        {"input": '{"token": "abc123"}', "expected": '{"token": "REDACTED"}'},
+        {
+            "input": '{"api_base": "https://api.example.com"}',
+            "expected": '{"api_base": "REDACTED"}',
+        },
+        {
+            "input": '{"non_sensitive": "value", "credentials": "secret"}',
+            "expected": '{"non_sensitive": "value", "credentials": "REDACTED"}',
+        },
+    ]
+
+    for test_case in test_cases:
+        # Create a log record
+        record = logging.LogRecord(
+            name="test_logger",
+            level=logging.INFO,
+            pathname="test.py",
+            lineno=1,
+            msg=test_case["input"],
+            args=(),
+            exc_info=None,
+        )
+
+        # Apply the filter
+        sensitive_filter.filter(record)
+
+        # Verify the output
+        assert (
+            record.msg == test_case["expected"]
+        ), f"Failed for input: {test_case['input']}"
+
+
+def test_sensitive_data_filter_with_different_formats():
+    # Create a test logger
+    logger = logging.getLogger("test_logger")
+    logger.setLevel(logging.INFO)
+
+    # Create a filter
+    sensitive_filter = SensitiveDataFilter()
+
+    # Test different formats
+    test_cases = [
+        {"input": "api_key=sk-1234567890", "expected": "api_key=REDACTED"},
+        {
+            "input": "'credentials': 'secret123'",
+            "expected": "'credentials': 'REDACTED'",
+        },
+        {"input": "\"token\": 'abc123'", "expected": "\"token\": 'REDACTED'"},
+    ]
+
+    for test_case in test_cases:
+        # Create a log record
+        record = logging.LogRecord(
+            name="test_logger",
+            level=logging.INFO,
+            pathname="test.py",
+            lineno=1,
+            msg=test_case["input"],
+            args=(),
+            exc_info=None,
+        )
+
+        # Apply the filter
+        sensitive_filter.filter(record)
+
+        # Verify the output
+        assert (
+            record.msg == test_case["expected"]
+        ), f"Failed for input: {test_case['input']}"