| # 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. |
| |
| |
| class SystemProperties(dict): |
| |
| """A dict interface to interact with device system properties. |
| |
| System properties are key/value pairs as exposed by adb shell getprop/setprop. |
| |
| This implementation minimizes interaction with the physical device. It is |
| valid for the lifetime of a boot. |
| """ |
| |
| def __init__(self, android_commands): |
| super(SystemProperties, self).__init__() |
| self._adb = android_commands |
| self._cached_static_properties = {} |
| |
| def __getitem__(self, key): |
| if self._IsStatic(key): |
| if key not in self._cached_static_properties: |
| self._cached_static_properties[key] = self._GetProperty(key) |
| return self._cached_static_properties[key] |
| return self._GetProperty(key) |
| |
| def __setitem__(self, key, value): |
| # TODO(tonyg): This can fail with no root. Verify that it succeeds. |
| self._adb.SendShellCommand('setprop %s "%s"' % (key, value), retry_count=3) |
| |
| @staticmethod |
| def _IsStatic(key): |
| # TODO(tonyg): This list is conservative and could be expanded as needed. |
| return (key.startswith('ro.boot.') or |
| key.startswith('ro.build.') or |
| key.startswith('ro.product.')) |
| |
| def _GetProperty(self, key): |
| return self._adb.SendShellCommand('getprop %s' % key, retry_count=3).strip() |
