Extension docs server: many changes to bring down the latency of the server,

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

 # Copyright (c) 2012 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 os
+from request_scoped_fs_cache import RequestScopedFsCache
 
 class FileSystemCache(object):
   """This class caches FileSystem data that has been processed.
   """
   class Builder(object):
     """A class to build a FileSystemCache.
     """
     def __init__(self, file_system):
       self._file_system = file_system
 
     def build(self, populate_function):
       return FileSystemCache(self._file_system, populate_function)
 
   class _CacheEntry(object):
     def __init__(self, cache_data, version):
       self._cache_data = cache_data
       self.version = version
 
   def __init__(self, file_system, populate_function):
     self._file_system = file_system
     self._populate_function = populate_function
     self._cache = {}
 
+  def ScopeToRequest(self):
+    return RequestScopedFsCache(self)
+
   def _RecursiveList(self, files):
     all_files = files[:]
     dirs = {}
     for filename in files:
       if filename.endswith('/'):
         all_files.remove(filename)
         dirs.update(self._file_system.Read([filename]).Get())
     for dir_, files in dirs.iteritems():
       all_files.extend(self._RecursiveList([dir_ + f for f in files]))
     return all_files
@@ skipping 22 matching lines @@
     if path in self._cache:
       if version > self._cache[path].version:
         self._cache.pop(path)
       else:
         return self._cache[path]._cache_data
     cache_data = self._RecursiveList(
         [path + f for f in self._file_system.ReadSingle(path)])
     self._cache[path] = self._CacheEntry(self._populate_function(cache_data),
                                          version)
     return self._cache[path]._cache_data