src/tools/telemetry/telemetry/core/backends/chrome/extension_dict_backend.py

   1 # Copyright 2013 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4 import json
   5 import re
   6 import weakref
   7
   8 from telemetry.core import extension_page
   9 from telemetry.core.backends.chrome import inspector_backend
  10
  11 class ExtensionNotFoundException(Exception):
  12   pass
  13
  14 class ExtensionDictBackend(object):
  15   def __init__(self, browser_backend):
  16     self._browser_backend = browser_backend
  17     # Maps extension ids to ExtensionPage objects.
  18     self._extension_dict = weakref.WeakValueDictionary()
  19
  20   def __getitem__(self, extension_id):
  21     extension_object = self._extension_dict.get(extension_id)
  22     if not extension_object:
  23       extension_object = self._CreateExtensionObject(extension_id)
  24       assert extension_object
  25       self._extension_dict[extension_id] = extension_object
  26     return extension_object
  27
  28   def __contains__(self, extension_id):
  29     return extension_id in self._GetExtensionIds()
  30
  31   @staticmethod
  32   def _ExtractExtensionId(url):
  33     m = re.match(r"(chrome-extension://)([^/]+)", url)
  34     assert m
  35     return m.group(2)
  36
  37   @staticmethod
  38   def _GetExtensionId(extension_info):
  39     if 'url' not in extension_info:
  40       return None
  41     return ExtensionDictBackend._ExtractExtensionId(extension_info['url'])
  42
  43   def _CreateExtensionObject(self, extension_id):
  44     extension_info = self._FindExtensionInfo(extension_id)
  45     if not extension_info or not 'webSocketDebuggerUrl' in extension_info:
  46       raise ExtensionNotFoundException()
  47     return extension_page.ExtensionPage(
  48         extension_id,
  49         extension_info['url'],
  50         self._CreateInspectorBackendForDebuggerUrl(
  51             extension_info['webSocketDebuggerUrl']))
  52
  53   def _CreateInspectorBackendForDebuggerUrl(self, debugger_url):
  54     return inspector_backend.InspectorBackend(self._browser_backend.browser,
  55                                               self._browser_backend,
  56                                               debugger_url)
  57
  58   def _FindExtensionInfo(self, extension_id):
  59     for extension_info in self.GetExtensionInfoList():
  60       if self._GetExtensionId(extension_info) == extension_id:
  61         return extension_info
  62     return None
  63
  64   def GetExtensionInfoList(self, timeout=None):
  65     data = self._browser_backend.Request('', timeout=timeout)
  66     return self._FilterExtensions(json.loads(data))
  67
  68   def _FilterExtensions(self, all_pages):
  69     return [page_info for page_info in all_pages
  70             if page_info['url'].startswith('chrome-extension://')]
  71
  72   def _GetExtensionIds(self):
  73     return map(self._GetExtensionId, self.GetExtensionInfoList())