Add support for deprecated json.RESERVED_ATTRS

src/pythonjsonlogger/json.py

@@ -15,6 +15,7 @@
 import json
 import traceback
 from typing import Any, Callable, Optional, Union
+import warnings
 
 ## Application
 from . import core
@@ -97,3 +98,15 @@ def jsonify_log_record(self, log_record: core.LogRecord) -> str:
             indent=self.json_indent,
             ensure_ascii=self.json_ensure_ascii,
         )
+
+
+### DEPRECATED COMPATIBILITY
+### ============================================================================
+def __getattr__(name: str):
+    if name == "RESERVED_ATTRS":
+        warnings.warn(
+            "RESERVED_ATTRS has been moved to pythonjsonlogger.core",
+            DeprecationWarning,
+        )
+        return core.RESERVED_ATTRS
+    raise AttributeError(f"module {__name__} has no attribute {name}")

tests/test_deprecation.py

@@ -18,3 +18,11 @@ def test_jsonlogger_deprecated():
     with pytest.deprecated_call():
         pythonjsonlogger.jsonlogger
     return
+
+
+def test_jsonlogger_reserved_attrs_deprecated():
+    with pytest.deprecated_call():
+        # Note: We use json instead of jsonlogger as jsonlogger will also produce
+        # a DeprecationWarning and we specifically want the one for RESERVED_ATTRS
+        pythonjsonlogger.json.RESERVED_ATTRS
+    return