Devserver: run the cron over the examples.

chrome/common/extensions/docs/server2/local_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 os
 
-import file_system
+from file_system import FileSystem, FileNotFoundError, StatInfo, ToUnicode
 from future import Future
 
-class LocalFileSystem(file_system.FileSystem):
+class LocalFileSystem(FileSystem):
   """FileSystem implementation which fetches resources from the local
   filesystem.
   """
   def __init__(self, base_path):
     self._base_path = self._ConvertToFilepath(base_path)
 
   def _ConvertToFilepath(self, path):
     return path.replace('/', os.sep)
 
   def _ReadFile(self, filename, binary):
     try:
       mode = 'rb' if binary else 'r'
       with open(os.path.join(self._base_path, filename), mode) as f:
         contents = f.read()
         if binary:
           return contents
-        return file_system.ToUnicode(contents)
-    except IOError:
-      raise file_system.FileNotFoundError(filename)
+        return ToUnicode(contents)
+    except IOError as e:
+      raise FileNotFoundError('Read failed for %s: %s' % (filename, e))
 
   def _ListDir(self, dir_name):
     all_files = []
     full_path = os.path.join(self._base_path, dir_name)
     try:
       files = os.listdir(full_path)
-    except OSError:
-      raise file_system.FileNotFoundError(dir_name)
+    except OSError as e:
+      raise FileNotFoundError('os.listdir failed for %s: %s' % (dir_name, e))
     for path in files:
       if path.startswith('.'):
         continue
       if os.path.isdir(os.path.join(full_path, path)):
         all_files.append(path + '/')
       else:
         all_files.append(path)
     return all_files
 
   def Read(self, paths, binary=False):
     result = {}
     for path in paths:
       if path.endswith('/'):
         result[path] = self._ListDir(self._ConvertToFilepath(path))
       else:
         result[path] = self._ReadFile(self._ConvertToFilepath(path), binary)
     return Future(value=result)
 
   def _CreateStatInfo(self, path):
     if path.endswith('/'):
       versions = dict((filename, os.stat(os.path.join(path, filename)).st_mtime)
                       for filename in os.listdir(path))
     else:
       versions = None
-    return file_system.StatInfo(os.stat(path).st_mtime, versions)
+    try:
+      return StatInfo(os.stat(path).st_mtime, versions)
+    except OSError as e:
+      raise FileNotFoundError('os.stat failed for %s: %s' % (path, e))
 
   def Stat(self, path):
-    try:
-      return self._CreateStatInfo(os.path.join(self._base_path, path))
-    except OSError:
-      raise file_system.FileNotFoundError(path)
+    return self._CreateStatInfo(os.path.join(self._base_path, path))