Refactor removing log handlers

src/ocrmypdf/builtin_plugins/concurrency.py

@@ -29,6 +29,7 @@ from tqdm import tqdm
 from ocrmypdf import Executor, hookimpl
 from ocrmypdf._logging import TqdmConsole
 from ocrmypdf.exceptions import InputFileError
+from ocrmypdf.helpers import remove_all_log_handlers
 
 Queue = Union[multiprocessing.Queue, queue.Queue]
 
@@ -74,9 +75,7 @@ def process_init(q: Queue, user_init: Callable[[], None], loglevel):
 
     # Remove any log handlers that belong to the parent process
     root = logging.getLogger()
-    for handler in root.handlers[:]:
-        root.removeHandler(handler)
-        handler.close()  # To ensure handlers with opened resources are released
+    remove_all_log_handlers(root)
 
     # Set up our single log handler to forward messages to the parent
     root.setLevel(loglevel)

src/ocrmypdf/extra_plugins/awslambda.py

@@ -22,6 +22,7 @@ from unittest.mock import Mock
 from ocrmypdf import Executor, hookimpl
 from ocrmypdf._concurrent import NullProgressBar
 from ocrmypdf.exceptions import InputFileError
+from ocrmypdf.helpers import remove_all_log_handlers
 
 
 class MessageType(Enum):
@@ -61,8 +62,8 @@ def process_loop(
     # Reconfigure the root logger for this process to send all messages to a queue
     h = ConnectionLogHandler(conn)
     root = logging.getLogger()
+    remove_all_log_handlers(root)
     root.setLevel(loglevel)
-    root.handlers = []
     root.addHandler(h)
 
     user_init()

src/ocrmypdf/helpers.py

@@ -223,6 +223,13 @@ def clamp(n, smallest, largest):  # mypy doesn't understand types for this
     return max(smallest, min(n, largest))
 
 
+def remove_all_log_handlers(logger):
+    "Remove all log handlers, usually used in a child process."
+    for handler in logger.handlers[:]:
+        logger.removeHandler(handler)
+        handler.close()  # To ensure handlers with opened resources are released
+
+
 def pikepdf_enable_mmap():
     # try:
     #     if pikepdf._qpdf.set_access_default_mmap(True):