Worker only creates log handlers if there aren't any.

rq/logutils.py

@@ -16,10 +16,25 @@ from rq.utils import ColorizingStreamHandler
 
 def setup_loghandlers(level='INFO'):
     logger = logging.getLogger('rq.worker')
-    if not logger.handlers:
+    if not _has_effective_handler(logger):
         logger.setLevel(level)
         formatter = logging.Formatter(fmt='%(asctime)s %(message)s',
                                       datefmt='%H:%M:%S')
         handler = ColorizingStreamHandler()
         handler.setFormatter(formatter)
         logger.addHandler(handler)
+
+
+def _has_effective_handler(logger):
+    """
+    Checks if a logger has a handler that will catch its messages in its logger hierarchy.
+    :param `logging.Logger` logger: The logger to be checked.
+    :return: True if a handler is found for the logger, False otherwise.
+    :rtype: bool
+    """
+    while True:
+        if logger.handlers:
+            return True
+        if not logger.parent:
+            return False
+        logger = logger.parent