Cleanup machine based on the state in configuration file for mini installer test.

chrome/test/mini_installer/process_visitor.py

+# Copyright 2017 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 chrome_helper
+import visitor
+
+class ProcessVisitor(visitor.Visitor):
+  """ Visitor for Processes entry in property.
+  """
+  def _VisitEntry(self, entry_name, entry_value):
+    """ Check whether a process is running or not.
+
+        Args:
+          'entry_name' - A string represents the path to the process being
+                         verified.
+          'entry_value' - A dictionary with the following key and value:
+                          'running': a boolean indicating whether the process
+                          should be running.
+    """
+    running_process_paths = [path for (_, path) in
+                             chrome_helper.GetProcessIDAndPathPairs()]
+    process_path = self._variable_expander.Expand(entry_name)
+    is_running = process_path in running_process_paths
+    self._HandleProcess(is_running, entry_value['running'], process_path)
+
+  def _HandleProcess(self, is_running, should_process_run, process_path):
+    """ Abstract function to check process.
+
+        Args:
+          is_running: A boolean represents whether the process is running.
+          should_process_run: A boolean represents whether the process should
+                              keep running.
+          process_path: A string represents the path to the process.
+    """
+    raise NotImplementedError()
+
+class ProcessVerifier(ProcessVisitor):
+  """Verifies that the running processes match the expectation dictionaries."""
+  def _HandleProcess(self, is_running, should_process_run, process_path):
+    """ Overridden ProcessVisitor._HandleProcess to verify a process state.
+    """
+    error_message = ""
+    if is_running:
+      error_message = 'Process %s is running' % process_path
+    else:
+      error_message = 'Process %s is not running' % process_path
+    assert should_process_run == is_running, error_message