Initial auto update engine test harness.

This harness has support for test on vm machines.  It takes a base image and target image path, creates an update-enabled vm image from the base image and performs updates using cros_run_vm_update (vm wrapper around image_to_live).  It uses --snapshot for updating vm's and keeps them on (like a real machine would) so that the VM image is clean on the next test.

The current check in has two test cases -- updates without clobbering the stateful partition and updates with clobbering the stateful partition.

Change-Id: I5406eadb39fa36601d17f8dd15625bd6a8b38c15

BUG=6911
TEST=Ran through tests.

Review URL: http://codereview.chromium.org/3554002

bin/cros_au_test_harness

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+cros_au_test_harness.py

bin/cros_au_test_harness.py

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+#!/usr/bin/python
+
+# Copyright (c) 2010 The Chromium OS 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 optparse
+import os
+import sys
+import unittest
+
+sys.path.append(os.path.join(os.path.dirname(__file__), '../lib'))
+from cros_build_lib import RunCommand, Info, Warning
+
+_KVM_PID_FILE = '/tmp/harness_pid'
+_SCRIPTS_DIR = os.path.join(os.path.dirname(__file__), '..')
+_FULL_VDISK_SIZE = 6072
+_FULL_STATEFULFS_SIZE = 2048
+
+global base_image_path
+global target_image_path
+
+_VERIFY_SUITE = 'suite_Smoke'
+
+class AUTest(object):
+  """Abstract interface that defines an Auto Update test."""
+
+  def PrepareBase(self):
+    """Prepares target with base_image_path."""
+    pass
+
+  def UpdateImage(self, image_path, stateful_change='old'):
+    """Updates target with the image given by the image_path.
+
+    Args:
+      image_path:  Path to the image to update with.  This image must be a test
+        image.
+      stateful_change: How to modify the stateful partition.  Values are:
+          'old':  Don't modify stateful partition.  Just update normally.
+          'clean':  Uses clobber-state to wipe the stateful partition with the
+            exception of code needed for ssh.
+    """
+    pass
+
+  def VerifyImage(self):
+    """Verifies the image is correct."""
+    pass
+
+  def testFullUpdateKeepStateful(self):
+    # Prepare and verify the base image has been prepared correctly.
+    self.PrepareBase()
+    self.VerifyImage()
+
+    # Update to.
+    Info('Updating from base image on vm to target image.')
+    self.UpdateImage(target_image_path)
+    self.VerifyImage()
+
+    # Update from.
+    Info('Updating from updated image on vm back to base image.')
+    self.UpdateImage(base_image_path)
+    self.VerifyImage()
+
+  def testFullUpdateWipeStateful(self):
+    # Prepare and verify the base image has been prepared correctly.
+    self.PrepareBase()
+    self.VerifyImage()
+
+    # Update to.
+    Info('Updating from base image on vm to target image and wiping stateful.')
+    self.UpdateImage(target_image_path, 'clean')
+    self.VerifyImage()
+
+    # Update from.
+    Info('Updating from updated image back to base image and wiping stateful.')
+    self.UpdateImage(base_image_path, 'clean')
+    self.VerifyImage()
+
+
+class VirtualAUTest(unittest.TestCase, AUTest):
+  """Test harness for updating virtual machines."""
+  vm_image_path = None
+
+  def _KillExistingVM(self, pid_file):
+    if os.path.exists(pid_file):
+      Warning('Existing %s found.  Deleting and killing process' %
+              pid_file)
+      pid = RunCommand(['sudo', 'cat', pid_file], redirect_stdout=True,
+                       enter_chroot=False)
+      if pid:
+        RunCommand(['sudo', 'kill', pid.strip()], error_ok=True,
+                   enter_chroot=False)
+        RunCommand(['sudo', 'rm', pid_file], enter_chroot=False)
+
+  def setUp(self):
+    """Unit test overriden method.  Is called before every test."""
+
+    self._KillExistingVM(_KVM_PID_FILE)
+
+  def PrepareBase(self):
+    """Creates an update-able VM based on base image."""
+
+    self.vm_image_path = ('%s/chromiumos_qemu_image.bin' % os.path.dirname(
+          base_image_path))
+    if not os.path.exists(self.vm_image_path):
+      Info('Qemu image not found, creating one.')
+      RunCommand(['%s/image_to_vm.sh' % _SCRIPTS_DIR,
+                  '--full',
+                  '--from %s' % os.path.dirname(base_image_path),
+                  '--vdisk_size %s' % _FULL_VDISK_SIZE,
+                  '--statefulfs_size %s' % _FULL_STATEFULFS_SIZE,
+                  '--test_image'], enter_chroot=True)
+    else:
+      Info('Using existing VM image')
+
+    self.assertTrue(os.path.exists(self.vm_image_path))
+
+  def UpdateImage(self, image_path, stateful_change='old'):
+    """Updates VM image with image_path."""
+
+    stateful_change_flag = ''
+    if stateful_change:
+      stateful_change_flag = '--stateful_flags=%s' % stateful_change
+
+    RunCommand(['%s/cros_run_vm_update' % os.path.dirname(__file__),
+                '--update_image_path=%s' % image_path,
+                '--vm_image_path=%s' % self.vm_image_path,
+                '--snapshot',
+                '--persist',
+                '--kvm_pid=%s' % _KVM_PID_FILE,
+                stateful_change_flag,
+               ], enter_chroot=False)
+
+  def VerifyImage(self):
+    """Runs vm smoke suite to verify image."""
+
+    # image_to_live already verifies lsb-release matching.  This is just
+    # for additional steps.
+
+    # TODO(sosa):  Compare output with results of base image.
+    RunCommand(['%s/cros_run_vm_test' % os.path.dirname(__file__),
+                '--image_path=%s' % self.vm_image_path,
+                '--snapshot',
+                '--persist',
+                '--kvm_pid=%s' % _KVM_PID_FILE,
+                '--test_case=%s' % _VERIFY_SUITE,
+               ], error_ok=True, enter_chroot=False)
+
+
+if __name__ == '__main__':
+  parser = optparse.OptionParser()
+  parser.add_option('-b', '--base_image',
+                    help='path to the base image.')
+  parser.add_option('-t', '--target_image',
+                    help='path to the target image')
+  # Set the usage to include flags.
+  parser.set_usage(parser.format_help())
+  # Parse existing sys.argv so we can pass rest to unittest.main.
+  (options, sys.argv) = parser.parse_args(sys.argv)
+
+  base_image_path = options.base_image
+  target_image_path = options.target_image
+
+  if not base_image_path:
+    parser.error('Need path to base image for vm.')
+
+  if not target_image_path:
+    parser.error('Need path to target image to update with.')
+
+  unittest.main()