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

   1 # Copyright 2014 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 logging
   6 import posixpath
   7
   8 from custom_logger import CustomLogger
   9 from extensions_paths import EXAMPLES
  10 from file_system_util import CreateURLsFromPaths
  11 from future import Future
  12 from render_servlet import RenderServlet
  13 from special_paths import SITE_VERIFICATION_FILE
  14 from timer import Timer
  15
  16
  17 _SUPPORTED_TARGETS = {
  18   'examples': (EXAMPLES, 'extensions/examples'),
  19 }
  20
  21
  22 _log = CustomLogger('render_refresher')
  23
  24
  25 class _SingletonRenderServletDelegate(RenderServlet.Delegate):
  26   def __init__(self, server_instance):
  27     self._server_instance = server_instance
  28
  29   def CreateServerInstance(self):
  30     return self._server_instance
  31
  32
  33 def _RequestEachItem(title, items, request_callback):
  34   '''Runs a task |request_callback| named |title| for each item in |items|.
  35   |request_callback| must take an item and return a servlet response.
  36   Returns true if every item was successfully run, false if any return a
  37   non-200 response or raise an exception.
  38   '''
  39   _log.info('%s: starting', title)
  40   success_count, failure_count = 0, 0
  41   timer = Timer()
  42   try:
  43     for i, item in enumerate(items):
  44       def error_message(detail):
  45         return '%s: error rendering %s (%s of %s): %s' % (
  46             title, item, i + 1, len(items), detail)
  47       try:
  48         response = request_callback(item)
  49         if response.status == 200:
  50           success_count += 1
  51         else:
  52           _log.error(error_message('response status %s' % response.status))
  53           failure_count += 1
  54       except Exception as e:
  55         _log.error(error_message(traceback.format_exc()))
  56         failure_count += 1
  57         if IsDeadlineExceededError(e): raise
  58   finally:
  59     _log.info('%s: rendered %s of %s with %s failures in %s',
  60         title, success_count, len(items), failure_count,
  61         timer.Stop().FormatElapsed())
  62   return success_count == len(items)
  63
  64
  65 class RenderRefresher(object):
  66   '''Used to refresh any set of renderable resources. Currently only supports
  67   assets related to extensions examples.'''
  68   def __init__(self, server_instance, request):
  69     self._server_instance = server_instance
  70     self._request = request
  71
  72   def GetRefreshPaths(self):
  73     return _SUPPORTED_TARGETS.keys()
  74
  75   def Refresh(self, path):
  76     def render(path):
  77       request = Request(path, self._request.host, self._request.headers)
  78       delegate = _SingletonRenderServletDelegate(self._server_instance)
  79       return RenderServlet(request, delegate).Get()
  80
  81     def request_files_in_dir(path, prefix='', strip_ext=None):
  82       '''Requests every file found under |path| in this host file system, with
  83       a request prefix of |prefix|. |strip_ext| is an optional list of file
  84       extensions that should be stripped from paths before requesting.
  85       '''
  86       def maybe_strip_ext(name):
  87         if name == SITE_VERIFICATION_FILE or not strip_ext:
  88           return name
  89         base, ext = posixpath.splitext(name)
  90         return base if ext in strip_ext else name
  91       files = [maybe_strip_ext(name)
  92                for name, _ in CreateURLsFromPaths(master_fs, path, prefix)]
  93       return _RequestEachItem(path, files, render)
  94
  95     # Only support examples for now.
  96     if path not in _SUPPORTED_TARGETS:
  97       return Future(callback=lambda: False)
  98
  99     dir = _SUPPORTED_TARGETS[path][0]
 100     prefix = _SUPPORTED_TARGETS[path][1]
 101     return request_files_in_dir(dir, prefix=prefix)