Initial commit for the Automated Installer Testing Framework.

chrome/test/mini_installer/test_installer.py

Index: chrome/test/mini_installer/test_installer.py
diff --git a/chrome/test/mini_installer/test_installer.py b/chrome/test/mini_installer/test_installer.py
new file mode 100644
index 0000000000000000000000000000000000000000..a1d2a6913a52e983ecb338284cccc5f027cfaee9
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+++ b/chrome/test/mini_installer/test_installer.py
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+# 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.
+
+"""This script tests the installer with test cases specified in the config file.
+
+For each test case, it checks that the machine states after the execution of
+each command match the expected machine states. For more details take a look at
+the design documentation at http://goo.gl/Q0rGM6
+"""
+
+import json
+import optparse
+import os
+import subprocess
+
+import settings
+import verifier
+
+
+class Config:
+  """Describes the machine states, actions, and test cases.
+
+  A state is a dictionary where each key is a verifier's name and the
+  associated value is the input to that verifier. An action is a shorthand for
+  a command. A test is array of alternating state names and action names,
+  starting and ending with state names. An instance of this class stores a map
+  from state names to state objects, a map from action names to commands, and
+  an array of test objects.
+  """
+  def __init__(self):
+    self.states = {}
+    self.actions = {}
+    self.tests = []
+
+
+def MergePropertyDictionaries(current_property, new_property):
+  """Merges the new Property object into the current Property object.
+
+  This is different from general dictionary merging in that, in case there are
+  properties with the same name, we merge values together in the first level,
+  and we override earlier values in the second level.
+
+  Args:
+    current_property: The Property object to be modified.
+    new_property: The new Property object.
+  """
+  for key, value in new_property.iteritems():
+    if key not in current_property:
+      current_property[key] = value
+    else:
+      assert(isinstance(current_property[key], dict) and
+          isinstance(value, dict))
+      # This merges two dictionaries together. In case there are properties with
+      # the same name, the latter will override the former.
+      current_property[key] = dict(
+          current_property[key].items() + value.items())
+
+
+def ParsePropertyFiles(directory, filenames):
+  """Parses an array of .prop files.
+
+  Args:
+    property_filenames: An array of Property filenames.
+    directory: The directory where the Config file and all Property files
+        reside in.
+
+  Returns:
+    A Property object created by merging all Property objects specified in
+        the array.
+  """
+  current_property = {}
+  for filename in filenames:
+    path = os.path.join(directory, filename)
+    new_property = json.load(open(path))
+    MergePropertyDictionaries(current_property, new_property)
+  return current_property
+
+
+def ParseConfigFile(filename):
+  """Parses a .config file.
+
+  Args:
+    config_filename: A Config filename.
+
+  Returns:
+    A config object.
+  """
+  config_data = json.load(open(filename, 'r'))
+  directory = os.path.dirname(os.path.abspath(filename))
+
+  config = Config()
+  config.tests = config_data['tests']
+  for state_name, state_property_filenames in config_data['states']:
+    config.states[state_name] = ParsePropertyFiles(directory,
+                                                   state_property_filenames)
+  for action_name, action_command in config_data['actions']:
+    config.actions[action_name] = action_command
+  return config
+
+
+def VerifyState(config, state):
+  """Verifies that the current machine states match the given machine states.
+
+  Args:
+    config: A Config object.
+    state: The current state.
+  """
+  # TODO(sukolsak): Think of ways of preserving the log when the test fails but
+  # not printing these when the test passes.
+  print settings.PRINT_STATE_PREFIX + state
+  verifier.Verify(config.states[state])
+
+
+def RunCommand(command):
+  print settings.PRINT_COMMAND_PREFIX + command
+  subprocess.call(command, shell=True)
+
+
+def RunResetCommand():
+  print settings.PRINT_COMMAND_PREFIX + 'Reset'
+  # TODO(sukolsak): Need to figure how exactly we want to reset.
+
+
+def Test(config):
+  """Tests the installer using the given Config object.
+
+  Args:
+    config: A Config object.
+  """
+  for test in config.tests:
+    print settings.PRINT_TEST_PREFIX + ' -> '.join(test)
+
+    # A Test object is an array of alternating state names and action names.
+    # The array starts and ends with states. Therefore, the length must be odd.
+    assert(len(test) % 2 == 1)
+
+    RunResetCommand()
+
+    current_state = test[0]
+    VerifyState(config, current_state)
+    # TODO(sukolsak): Quit the test early if VerifyState fails at any point.
+
+    for i in range(1, len(test), 2):
+      action = test[i]
+      RunCommand(config.actions[action])
+
+      current_state = test[i + 1]
+      VerifyState(config, current_state)
+
+
+def main():
+  usage = 'usage: %prog configfile'
+  parser = optparse.OptionParser(usage, description='Test the installer.')
+  (options, args) = parser.parse_args()
+  if len(args) != 1:
+    parser.error('incorrect number of arguments')
+
+  config = ParseConfigFile(args[0])
+  Test(config)
+
+
+if __name__ == '__main__':
+  main()