Adding the initial code for Omnibot multi-machine support

testing/legion/examples/hello_world/host_test.py

Index: testing/legion/examples/hello_world/host_test.py
diff --git a/testing/legion/examples/hello_world/host_test.py b/testing/legion/examples/hello_world/host_test.py
new file mode 100755
index 0000000000000000000000000000000000000000..a741df5114b0e2d6ba7929c09320d6d580b1b998
--- /dev/null
+++ b/testing/legion/examples/hello_world/host_test.py
@@ -0,0 +1,75 @@
+#!/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 host test module.
+
+This module runs on the host machine and is responsible for creating 2
+client machines, waiting for them, and running RPC calls on them.
+"""
+
+# Map the legion directory so we can import the host controller.
+import sys
+sys.path.append('../../')
+
+import logging
+import time
+
+import host_controller
+
+
+class ExampleController(host_controller.HostController):
+  """A simple example controller for a test."""
+
+  def __init__(self):
+    super(ExampleController, self).__init__()
+    self.client1 = None
+    self.client2 = None
+
+  def CreateClient(self):
+    """Create a client object and set the proper values."""
+    client = self.NewClient('client_test.isolate')
+    client.AddConfigVars('os', 'Linux')

[Marc-Antoine Ruel (Google), 2015/01/30 21:58:41]

Why not pass all these in the constructor? It'd make the object more immutable
and easier to manage.

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

Done.

+    client.AddConfigVars('multi_machine', '1')
+    client.AddDimension('os', 'Linux')
+    client.priority = 0
+    client.rpc_timeout = 90
+    client.verbose = True
+    client.Create()
+    return client
+
+  def SetUp(self):
+    """Create the client machines and wait until they connect.
+
+    In this call the actual creation of the client machines is done in parallel
+    by the system. The WaitForConnect calls are performed in series but will
+    return as soon as the client connects.
+    """
+    self.client1 = self.CreateClient()
+    self.client2 = self.CreateClient()
+    self.client1.WaitForConnection(120)
+    self.client2.WaitForConnection(120)
+
+  def Test(self):
+    """Run the actual test."""
+    self.CallEcho(self.client1)
+    self.CallEcho(self.client2)
+    self.CallClientTest(self.client1)
+    self.CallClientTest(self.client2)
+
+  def CallEcho(self, client):
+    """Call rpc.Echo on a client."""
+    logging.info('Calling Echo on %s', client.name)
+    logging.info(self.client1.rpc.Echo(client.name))
+
+  def CallClientTest(self, client):
+    """Call client_test.py name on a client."""
+    logging.info('Calling Subprocess on %s to run "client_test.py %s"',
+                 client.name, client.name)
+    retcode, stdout, stderr = client.rpc.Subprocess(
+        ['./client_test.py', client.name])
+    logging.info('retcode: %s, stdout: %s, stderr: %s', retcode, stdout, stderr)
+
+
+if __name__ == '__main__':
+  ExampleController().RunController()