Docserver: Generate a table of extension/app API owners

chrome/common/extensions/docs/server2/caching_file_system.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 posixpath
 import sys
 
 from file_system import FileSystem, StatInfo, FileNotFoundError
 from future import Future
 from path_util import IsDirectory, ToDirectory
@@ skipping 42 matching lines @@
         return dir_stat
       # Was a file stat. Extract that file.
       file_version = dir_stat.child_versions.get(file_path)
       if file_version is None:
         raise FileNotFoundError('No stat found for %s in %s (found %s)' %
                                 (path, dir_path, dir_stat.child_versions))
       return StatInfo(file_version)
 
     dir_stat = self._stat_object_store.Get(dir_path).Get()
     if dir_stat is not None:
-      return Future(value=make_stat_info(dir_stat))
+      return Future(value=dir_stat).Then(make_stat_info)

[ahernandez, 2014/08/21 18:07:27]

I had to change it to this to avoid FileNotFoundErrors from being prematurely
raised.

[not at google - send to devlin, 2014/08/21 21:39:57]

Heh, I needed to make that fix as well:

https://codereview.chromium.org/429723005/diff/100001/chrome/common/extension...

(I haven't had time to finish that patch obviously)

Anyhow, I slightly prefer using a callback rather than .Then().

 
     def next(dir_stat):
       assert dir_stat is not None  # should have raised a FileNotFoundError
       # We only ever need to cache the dir stat.
       self._stat_object_store.Set(dir_path, dir_stat)
       return make_stat_info(dir_stat)
     return self._MemoizedStatAsyncFromFileSystem(dir_path).Then(next)
 
   @memoize
   def _MemoizedStatAsyncFromFileSystem(self, dir_path):
@@ skipping 51 matching lines @@
       return new_results
     # Read in the values that were uncached or old.
     return self._file_system.Read(set(paths) - set(fresh_data.iterkeys()),
                                   skip_not_found=skip_not_found).Then(next)
 
   def GetIdentity(self):
     return self._file_system.GetIdentity()
 
   def __repr__(self):
     return '%s of <%s>' % (type(self).__name__, repr(self._file_system))