Adding the initial code for Omnibot multi-machine support

testing/legion/client_controller.py

+#!/usr/bin/env python
+# 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.
+"""The main client_controller code.

[Marc-Antoine Ruel (Google), 2015/01/30 18:00:21]

FYI, we generally keep an empty line in between the module docstring and the
other items.

[Mike Meade, 2015/01/30 21:04:04]

Done.

+
+This code is the main entry point for the client machines and handles
+registering with the host server and running the local RPC server.
+"""
+import argparse
+import logging
+import socket
+import sys
+import time
+
+#pylint: disable=relative-import
+import client_rpc_server
+import common_lib
+import discovery_server
+
+
+def RegisterClient(host, otp):
+  """Register this client with the host's discovery server."""
+  server = discovery_server.DiscoveryServer.Connect(host)
+  logging.info(
+      'Registering with discovery server using OTP %s', otp)
+  server.RegisterClient(otp, common_lib.MY_IP)
+
+
+def GetArgs():

[Marc-Antoine Ruel (Google), 2015/01/30 18:00:21]

Is there value in making it a function vs embedding in main() directly?

[Mike Meade, 2015/01/30 21:04:04]

Not explicitly. I was just trying to group by operation. I moved all of this
code into main.

+  """Parse the command line arguments."""
+  parser = argparse.ArgumentParser()
+  parser.add_argument('--otp')
+  parser.add_argument('--host')
+  parser.add_argument('--idle-timeout', type=int)
+  args, _ = parser.parse_known_args()
+  return args
+
+
+def CreateRPCServer(host, idle_timeout=None):
+  """Create the client RPC server.
+
+  Args:
+    host: The address of the host machine.
+    idle_timeout: The timeout in seconds to set.
+
+  Returns:
+    An instance of client_rpc_server.RPCServer.
+  """
+  server = client_rpc_server.RPCServer()

[Marc-Antoine Ruel (Google), 2015/01/30 18:00:21]

same

[Mike Meade, 2015/01/30 21:04:04]

Done.

+  server.AddAuthorizedAddress(host)
+  if idle_timeout:
+    server.SetIdleTimeout(idle_timeout)
+  return server
+
+
+def main():
+  common_lib.InitLogging()
+  common_lib.LogCommandLine()
+  logging.info('Client controller starting')
+  args = GetArgs()
+  RegisterClient(args.host, args.otp)
+  server = CreateRPCServer(args.host, args.idle_timeout)
+  server.serve_forever()
+
+
+if __name__ == '__main__':
+  main()