Add test_server_setup.py and add support for additional flags.

build/android/pylib/host_driven/test_server_setup.py

+#!/usr/bin/python
+# Copyright 2013 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.
+
+import os
+import os.path
+import subprocess
+
+from pylib import constants
+
+# NOTE: when adding or modifying these lines, omit any leading slashes!
+# Otherwise os.path.join() will (correctly) treat them as absolute paths
+# instead of relative paths, and will do nothing.
+PYTHONPATH_DIRS = [

[frankf, 2013/08/29 00:07:19]

Add a leading underscore since these are private. Same below.

[nyquist, 2013/08/29 23:59:43]

Done.

+    'net/tools/testserver/',
+    'third_party/',
+    'third_party/pyftpdlib/src/',
+    'third_party/pywebsocket/src',
+    'third_party/tlslite/',
+]
+
+# Python files in these directories are generated as part of the build.
+# These dirs are located in out/(Debug|Release) directory.
+# The correct path is determined based on the build type. E.g. out/Debug for
+# debug builds and out/Release for release builds.
+GENERATED_PYTHONPATH_DIRS = [
+    'pyproto/sync/protocol/',
+    'pyproto/'
+]
+

[frankf, 2013/08/29 00:07:19]

run gpylint. 2 blank lines between top-level declarations.

[nyquist, 2013/08/29 23:59:43]

Done.

+def SetUpTestServer(adb, shard_index, test_server_port, test_server_path):

[frankf, 2013/08/29 00:07:19]

So it makes sense to make this into a class and encapsulate the test_server
object below. You can then add a kill method to this class.

[nyquist, 2013/08/29 23:59:43]

Done.

+  """Sets up a server.
+
+  Args:
+    adb: AndroidCommands object.
+    shard_index: Index of the current shard.
+    test_server_port: port to run the test server on.

[frankf, 2013/08/29 00:07:19]

Capital first letter.

[nyquist, 2013/08/29 23:59:43]

Done.

+    test_server_path: the path (relative to the root src dir) of the server
+
+  Returns:
+    A tuple where the first element is the port used by the server, and the
+    second is the mock server that was setup.
+  """
+  port = test_server_port + shard_index
+
+  src_dir = constants.DIR_SOURCE_ROOT
+  # Make dirs into a list of absolute paths.
+  abs_dirs = [os.path.join(src_dir, d) for d in PYTHONPATH_DIRS]
+  # Add the generated python files to the path
+  abs_dirs.extend([os.path.join(src_dir, 'out', constants.GetBuildType(), d)
+                   for d in GENERATED_PYTHONPATH_DIRS])
+  # Note the colon after $PYTHONPATH. This appends the list of PYTHONPATH_DIRS
+  # to the existing PYTHONPATH.
+  python_path = '$PYTHONPATH:' + ':'.join(abs_dirs)

[craigdh, 2013/08/29 00:06:46]

just modify os.environ

[nyquist, 2013/08/29 23:59:43]

Uses os.environ now, but does not edit it here, since it should only be applied
to the sub process.

+
+  # NOTE: A separate python process is used to simplify getting the right system
+  # path for finding includes.
+  server_flags = ['python', os.path.join(src_dir, test_server_path),
+                  '--log-to-console',
+                  ('--host=%s' % constants.TEST_SERVER_HOST),
+                  ('--port=%d' % port)]
+  test_server = subprocess.Popen(server_flags, env={'PYTHONPATH': python_path})

[craigdh, 2013/08/29 00:06:46]

We've had issues with bugs in Python 2.x's subprocess modules lead to major
flakiness in the past. There are a variety of workarounds implemented in
pylib/cmd_helper.py and I've made the replacement public in the FlagChanger
patch so you can just replace this subprocess.Popen() with cmd_helper.Call().

[nyquist, 2013/08/29 23:59:43]

There is no waiting for output here, so that does not work.

[craigdh, 2013/08/30 17:55:50]

Ah, you're right, I thought it was returning a Popen object. You're fine with
subprocess for now, if we see issues we can add a Popen replacement to
cmd_helper.

+  return (port, test_server)