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

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

Index: chrome/common/extensions/docs/server2/request_scoped_fs_cache.py
diff --git a/chrome/common/extensions/docs/server2/request_scoped_fs_cache.py b/chrome/common/extensions/docs/server2/request_scoped_fs_cache.py
new file mode 100644
index 0000000000000000000000000000000000000000..b92732b19ea36dfae213e070a8f8f2699d570cf7
--- /dev/null
+++ b/chrome/common/extensions/docs/server2/request_scoped_fs_cache.py
@@ -0,0 +1,23 @@
+# Copyright 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.
+
+class RequestScopedFsCache(object):
+  def __init__(self, delegate):
+    self._delegate = delegate
+    self._file_cache = {}
+    self._ls_cache = {}
+
+  def GetFromFile(self, path):
+    if path in self._file_cache:
+      return self._file_cache[path]
+    from_delegate = self._delegate.GetFromFile(path)
+    self._file_cache[path] = from_delegate
+    return from_delegate
+
+  def GetFromFileListing(self, path):
+    if path in self._ls_cache:
+      return self._ls_cache[path]
+    from_delegate = self._delegate.GetFromFileListing(path)
+    self._ls_cache[path] = from_delegate
+    return from_delegate