infra_libs/logs: Check if log directory exists.

infra_libs/logs/logs.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Utilities for logging.
 
 Example usage:
 
 .. code-block:: python
 
@@ skipping 240 matching lines @@
     _add_file_handlers(options, logger)
 
 
 def _add_file_handlers(options, logger):  # pragma: no cover
   # Test whether we can write to the log directory.  If not, write to a
   # temporary directory instead.  One of the DEFAULT_LOG_DIRECTORIES are created
   # on the real production machines by puppet, so /tmp should only be used when
   # running locally on developers' workstations.
   logs_directory = tempfile.gettempdir()
   for directory in options.logs_directory.split(os.pathsep):
+    if not os.path.isdir(directory):
+      continue
+
     try:
       with tempfile.TemporaryFile(dir=directory):
         pass
     except OSError:
       pass
     else:
       logs_directory = directory
       break
 
   # Log files are named with this pattern:
@@ skipping 12 matching lines @@
   for level in file_levels:
     add_handler(
         logger,
         handler=logging.handlers.RotatingFileHandler(
             filename=os.path.join(
                 logs_directory, pattern % logging.getLevelName(level)),
             maxBytes=10 * 1024 * 1024,
             backupCount=10,
             delay=True),
         level=level)