ENH: Add clear capability to overload logger_warning

pypdf/__init__.py

@@ -11,13 +11,15 @@
 from ._merger import PdfFileMerger, PdfMerger
 from ._page import PageObject, Transformation
 from ._reader import DocumentInformation, PdfFileReader, PdfReader
+from ._utils import overload_logger_warning
 from ._version import __version__
 from ._writer import ObjectDeletionFlag, PdfFileWriter, PdfWriter
 from .pagerange import PageRange, parse_filename_page_ranges
 from .papersizes import PaperSize
 
 __all__ = [
     "__version__",
+    "overload_logger_warning",
     "PageRange",
     "PaperSize",
     "DocumentInformation",

pypdf/_utils.py

@@ -430,6 +430,20 @@ def deprecation_no_replacement(name: str, removed_in: str = "3.0.0") -> None:
     deprecation(DEPR_MSG_NO_REPLACEMENT_HAPPENED.format(name, removed_in))
 
 
+custom_logger_warning = None
+
+
+def overload_logger_warning(fn: Optional[Callable[[str, str], None]] = None) -> None:
+    """
+    overload the logger_warning with a customed function
+    Parameters:
+        fn : Customed function ; parameters : msg: str, src: str
+             None: reset to default
+    """
+    global custom_logger_warning
+    custom_logger_warning = fn
+
+
 def logger_warning(msg: str, src: str) -> None:
     """
     Use this instead of logger.warning directly.
@@ -446,7 +460,10 @@ def logger_warning(msg: str, src: str) -> None:
       pypdf could apply a robustness fix to still read it. This applies mainly
       to strict=False mode.
     """
-    logging.getLogger(src).warning(msg)
+    if custom_logger_warning is None:
+        logging.getLogger(src).warning(msg)
+    else:
+        custom_logger_warning(msg, src)
 
 
 def deprecation_bookmark(**aliases: str) -> Callable:

tests/test_utils.py

@@ -15,6 +15,7 @@
     deprecation_no_replacement,
     mark_location,
     matrix_multiply,
+    overload_logger_warning,
     parse_iso8824_date,
     read_block_backwards,
     read_previous_line,
@@ -368,3 +369,16 @@ def test_parse_datetime_err():
         parse_iso8824_date("D:20210408T054711Z")
     assert ex.value.args[0] == "Can not convert date: D:20210408T054711Z"
     assert parse_iso8824_date("D:20210408054711").tzinfo is None
+
+
+def test_overload_logger_warning(capsys):
+    path = RESOURCE_ROOT / "issue-297.pdf"
+
+    def my_logger(msg: str, src: str) -> None:
+        print("!!!!")  # noqa
+
+    overload_logger_warning(my_logger)
+    PdfReader(path, strict=False)
+    captured = capsys.readouterr()
+    assert captured.out == "!!!!\n"
+    overload_logger_warning()