Docserver: Generate a table of extension/app API owners

chrome/common/extensions/docs/server2/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 traceback
 
 from future import Future
 from path_util import (
     AssertIsDirectory, AssertIsValid, IsDirectory, IsValid, SplitParent,
@@ skipping 66 matching lines @@
       - If |skip_not_found| is True, the resulting object will not contain any
         mapping for that path.
       - Otherwise, and by default, a FileNotFoundError is raised. This is
         guaranteed to only happen once the Future has been resolved (Get()
         called).
 
     For any other failure, raises a FileSystemError.
     '''
     raise NotImplementedError(self.__class__)
 
-  def ReadSingle(self, path):
+  def ReadSingle(self, path, skip_not_found=False):
     '''Reads a single file from the FileSystem. Returns a Future with the same
-    rules as Read(). If |path| is not found raise a FileNotFoundError on Get().
+    rules as Read(). If |path| is not found raise a FileNotFoundError on Get(),
+    or if |skip_not_found| is True then return None.
     '''
     AssertIsValid(path)
-    read_single = self.Read([path])
-    return Future(callback=lambda: read_single.Get()[path])
+    read_single = self.Read([path], skip_not_found=skip_not_found)
+    return Future(callback=lambda: read_single.Get().get(path, None))
 
   def Exists(self, path):
     '''Returns a Future to the existence of |path|; True if |path| exists,
     False if not. This method will not throw a FileNotFoundError unlike
     the Read* methods, however it may still throw a FileSystemError.
 
     There are several ways to implement this method via the interface but this
     method exists to do so in a canonical and most efficient way for caching.
     '''
     AssertIsValid(path)
@@ skipping 34 matching lines @@
 
   def GetIdentity(self):
     '''The identity of the file system, exposed for caching classes to
     namespace their caches. this will usually depend on the configuration of
     that file system - e.g. a LocalFileSystem with a base path of /var is
     different to that of a SubversionFileSystem with a base path of /bar, is
     different to a LocalFileSystem with a base path of /usr.
     '''
     raise NotImplementedError(self.__class__)
 
-  def Walk(self, root):
+  def Walk(self, root, depth=-1):
     '''Recursively walk the directories in a file system, starting with root.
 
     Behaviour is very similar to os.walk from the standard os module, yielding
     (base, dirs, files) recursively, where |base| is the base path of |files|,
     |dirs| relative to |root|, and |files| and |dirs| the list of files/dirs in
-    |base| respectively.
+    |base| respectively. If |depth| is specified and greater than 0, Walk will
+    only recurse |depth| times.
 
     Note that directories will always end with a '/', files never will.
 
     If |root| cannot be found, raises a FileNotFoundError.
     For any other failure, raises a FileSystemError.
     '''
     AssertIsDirectory(root)
     basepath = root
 
-    def walk(root):
+    def walk(root, depth):
+      if depth == 0:
+        return
       AssertIsDirectory(root)
       dirs, files = [], []
 
       for f in self.ReadSingle(root).Get():
         if IsDirectory(f):
           dirs.append(f)
         else:
           files.append(f)
 
       yield root[len(basepath):].rstrip('/'), dirs, files
 
       for d in dirs:
-        for walkinfo in walk(root + d):
+        for walkinfo in walk(root + d, depth - 1):
           yield walkinfo
 
-    for walkinfo in walk(root):
+    for walkinfo in walk(root, depth):
       yield walkinfo
 
   def __eq__(self, other):
     return (isinstance(other, FileSystem) and
             self.GetIdentity() == other.GetIdentity())
 
   def __ne__(self, other):
     return not (self == other)
 
   def __repr__(self):
     return '<%s>' % type(self).__name__
 
   def __str__(self):
     return repr(self)