fail when logging config file is not found

radicale/log.py

@@ -24,7 +24,6 @@ http://docs.python.org/library/logging.config.html
 
 import logging
 import logging.config
-import os
 import signal
 import sys
 
@@ -47,26 +46,30 @@ class RemoveTracebackFilter(logging.Filter):
 def start(name="radicale", filename=None, debug=False):
     """Start the logging according to the configuration."""
     logger = logging.getLogger(name)
-    if filename and os.path.exists(filename):
+    if debug:
+        logger.setLevel(logging.DEBUG)
+    else:
+        logger.addFilter(RemoveTracebackFilter())
+    if filename:
         # Configuration taken from file
-        configure_from_file(logger, filename, debug)
+        try:
+            configure_from_file(logger, filename, debug)
+        except Exception as e:
+            raise RuntimeError("Failed to load logging configuration file %r: "
+                               "%s" % (filename, e)) from e
         # Reload config on SIGHUP (UNIX only)
         if hasattr(signal, "SIGHUP"):
             def handler(signum, frame):
-                configure_from_file(logger, filename, debug)
+                try:
+                    configure_from_file(logger, filename, debug)
+                except Exception as e:
+                    logger.error("Failed to reload logging configuration file "
+                                 "%r: %s", filename, e, exc_info=True)
             signal.signal(signal.SIGHUP, handler)
     else:
         # Default configuration, standard output
-        if filename:
-            logger.warning(
-                "WARNING: Logging configuration file %r not found, using "
-                "stderr" % filename)
         handler = logging.StreamHandler(sys.stderr)
         handler.setFormatter(
             logging.Formatter("[%(thread)x] %(levelname)s: %(message)s"))
         logger.addHandler(handler)
-    if debug:
-        logger.setLevel(logging.DEBUG)
-    else:
-        logger.addFilter(RemoveTracebackFilter())
     return logger