Initial commit for the Automated Installer Testing Framework.

chrome/test/mini_installer_test/test_installer.py

+# 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 a series of 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.
+
+Read the design documentation at http://goo.gl/Q0rGM6

[gab, 2013/07/31 13:45:16]

s/Read/For more details take a look at

[sukolsak, 2013/07/31 18:20:30]

Done.

+"""
+
+import argparse
+import json
+import os
+import settings
+import subprocess
+import verifier
+
+
+class Config:
+  """Describes the machine states, actions, and test cases."""
+
+  def __init__(self):
+    self.states = {}
+    self.actions = {}
+    self.tests = []
+
+
+def MergeProperties(current_property, new_property):
+  """Merges the new Property object into the current Property object
+
+  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))

[gab, 2013/07/31 13:45:16]

fix indent (i.e., wrap to '(' above)

[sukolsak, 2013/07/31 18:20:30]

Done.

+      current_property[key] = dict(
+          current_property[key].items() + value.items())

[gab, 2013/07/31 13:45:16]

Does this merge (i.e., override) properties with the same name? 

Either way, add a comment stating exactly what this does.

[sukolsak, 2013/07/31 18:20:30]

Yes. Comment added.

[gab, 2013/08/01 20:30:41]

Sounds good, can you make it clear in the spec then that we are going with the
merge strategy?

[sukolsak, 2013/08/02 22:59:55]

Done.

+
+
+def ParseProperty(property_filename, directory):

[gab, 2013/07/31 13:45:16]

I suggest flipping the arguments here since native system calls take directory
first than filename; it's probably more intuitive for experienced python
developers to have directory first than filename...

[sukolsak, 2013/07/31 18:20:30]

Done.

+  """Parses a .prop file.
+
+  Args:
+    property_filename: A Property filename.
+    directory: The directory where the Config file and
+        all Property files reside in.
+
+  Returns:
+    A Property object.
+  """
+  property_path = os.path.join(directory, property_filename)
+  with open(property_path, "r") as property_file:

[gab, 2013/07/31 13:45:16]

Any failure handling required here? Or will an exception be bubbled back up and
kill the test (that's ok) if it happens?

[sukolsak, 2013/07/31 18:20:30]

The exception IOError will be bubbled back up and kill the test.

+    return json.load(property_file)
+
+
+def ParseProperties(property_filenames, directory):

[gab, 2013/07/31 13:45:16]

Same comment here about argument order

[sukolsak, 2013/07/31 18:20:30]

Done.

+  """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 property_filename in property_filenames:
+    new_property = ParseProperty(property_filename, directory)
+    MergeProperties(current_property, new_property)
+  return current_property
+
+
+def ParseConfig(config_filename):
+  """Parses a .config file.
+
+  Args:
+    config_filename: A Config filename.
+
+  Returns:
+    A config object.
+  """
+  config = Config()
+
+  with open(config_filename, "r") as config_file:

[gab, 2013/07/31 13:45:16]

Does config_filename need to be absolute?

Either way the comments should specify that.

[sukolsak, 2013/07/31 18:20:30]

It can be relative or absolute. I think the open operator in most major
languages does this. So this is trivial.

+    config_data = json.load(config_file)
+  directory = os.path.dirname(os.path.abspath(config_filename))
+
+  for state_name, state_property_filenames in config_data["states"]:
+    config.states[state_name] = ParseProperties(state_property_filenames,
+                                    directory)

[gab, 2013/07/31 13:45:16]

fix indent

[sukolsak, 2013/07/31 18:20:30]

Done.

+  for action_name, action_command in config_data["actions"]:
+    config.actions[action_name] = action_command
+  config.tests = config_data["tests"]
+  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.
+  """
+  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 states and actions.
+    # 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)

[gab, 2013/07/31 13:45:16]

Add a TODO to quit the test early if VerifyState fails at any point here or
below (any later failure has no meaning if a previous state is incorrect).

[sukolsak, 2013/07/31 18:20:30]

Done.

+
+    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():
+  parser = argparse.ArgumentParser(description="Test the installer.")
+  parser.add_argument("config_filename", help="the config file")
+  args = parser.parse_args()
+
+  config = ParseConfig(args.config_filename)
+  Test(config)
+
+
+if __name__ == "__main__":
+  main()