chrome/common/extensions/docs/server2/intro_data_source.py

   1 # Copyright (c) 2012 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
   5 import os
   6
   7 from compiled_file_system import Unicode
   8 from data_source import DataSource
   9 from docs_server_utils import FormatKey
  10 from extensions_paths import INTROS_TEMPLATES, ARTICLES_TEMPLATES
  11 from file_system import FileNotFoundError
  12 from future import Future
  13 from third_party.handlebar import Handlebar
  14
  15
  16
  17 # TODO(kalman): rename this HTMLDataSource or other, then have separate intro
  18 # article data sources created as instances of it.
  19 class IntroDataSource(DataSource):
  20   '''This class fetches the intros for a given API. From this intro, a table
  21   of contents dictionary is created, which contains the headings in the intro.
  22   '''
  23
  24   def __init__(self, server_instance, request):
  25     self._request = request
  26     self._cache = server_instance.compiled_fs_factory.Create(
  27         server_instance.host_file_system_provider.GetTrunk(),
  28         self._MakeIntro,
  29         IntroDataSource)
  30     self._ref_resolver = server_instance.ref_resolver_factory.Create()
  31
  32   @Unicode
  33   def _MakeIntro(self, intro_path, intro):
  34     # Guess the name of the API from the path to the intro.
  35     api_name = os.path.splitext(intro_path.split('/')[-1])[0]
  36     return Handlebar(
  37         self._ref_resolver.ResolveAllLinks(intro,
  38                                            relative_to=self._request.path,
  39                                            namespace=api_name),
  40         name=intro_path)
  41
  42   def get(self, key):
  43     path = FormatKey(key)
  44     def get_from_base_path(base_path):
  45       return self._cache.GetFromFile('%s/%s' % (base_path, path)).Get()
  46     base_paths = (INTROS_TEMPLATES, ARTICLES_TEMPLATES)
  47     for base_path in base_paths:
  48       try:
  49         return get_from_base_path(base_path)
  50       except FileNotFoundError:
  51         continue
  52     # Not found. Do the first operation again so that we get a stack trace - we
  53     # know that it'll fail.
  54     get_from_base_path(base_paths[0])
  55     raise AssertionError()
  56
  57   def Cron(self):
  58     # TODO(kalman): Walk through the intros and articles directory.
  59     return Future(value=())