Adding the initial code for Omnibot multi-machine support

testing/legion/common_lib.py

+# Copyright 2015 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.
+"""Common library methods.
+
+These methods can be used by both the host and the client code.
+"""
+
+import argparse
+import logging
+import socket
+import sys
+import xmlrpclib
+import SimpleXMLRPCServer
+
+LOGGING_FORMAT = ('%(asctime)s %(filename)s:%(lineno)s %(levelname)s] '
+                  '%(message)s')
+LOGGING_DATE_FORMAT = '%H:%M:%S'
+MY_IP = socket.gethostbyname(socket.gethostname())
+
+
+def InitLogging():
+  """Initialize the logging module."""
+  parser = argparse.ArgumentParser()
+  parser.add_argument('--verbose', action='store_true')
+  args, _ = parser.parse_known_args()
+  level = logging.DEBUG if args.verbose else logging.INFO

[Marc-Antoine Ruel (Google), 2015/01/30 21:58:40]

(FYI) in generally we use ERROR as default.

[Mike Meade, 2015/02/03 01:18:09]

Unfortunately setting logging to error results in a swarming.py error if the
host controller doesn't log an error.

Triggered task: host_test/os=Linux/12c32ce015a1a2ac2b30f00fc4d65c3a55c0b1f8
ERROR  65767        swarming(619): No output found for task 255646b308400710
legion-bot-1: 255646b308400710 0

I had logging set to ERROR in that run. I can simply print the command line to
make sure there is something in stdout.

I also changed the parser so the user can simply pass --verbosity=INFO or any
other level name to get that level of logging. The ClientController also
supports this.

[M-A Ruel, 2015/02/03 01:48:40]

Ah! I can fix that later in the client code. It's an old historical reason that
doesn't apply anymore.

+  logging.basicConfig(format=LOGGING_FORMAT, datefmt=LOGGING_DATE_FORMAT,
+                      level=level)
+
+
+def LogCommandLine():
+  """Log the command line used to run this program."""
+  logging.debug(' '.join(sys.argv))