wptserve: Import the latest revision of wptserve-related files.

third_party/WebKit/Tools/Scripts/webkitpy/thirdparty/wpt/wpt/tools/wptserve/wptserve/stash.py

Index: third_party/WebKit/Tools/Scripts/webkitpy/thirdparty/wpt/wpt/tools/wptserve/wptserve/stash.py
diff --git a/third_party/WebKit/Tools/Scripts/webkitpy/thirdparty/wpt/wpt/tools/wptserve/wptserve/stash.py b/third_party/WebKit/Tools/Scripts/webkitpy/thirdparty/wpt/wpt/tools/wptserve/wptserve/stash.py
index b546191932240007fdd3bdba927caa0cfb18912a..b6bd6eed442a2c1e22c8cfb6d294fa810991a3de 100644
--- a/third_party/WebKit/Tools/Scripts/webkitpy/thirdparty/wpt/wpt/tools/wptserve/wptserve/stash.py
+++ b/third_party/WebKit/Tools/Scripts/webkitpy/thirdparty/wpt/wpt/tools/wptserve/wptserve/stash.py
@@ -2,7 +2,6 @@ import base64
 import json
 import os
 import uuid
-from multiprocessing import Process
 from multiprocessing.managers import BaseManager, DictProxy
 
 class ServerDictManager(BaseManager):
@@ -57,18 +56,19 @@ def start_server(address=None, authkey=None):
 #TODO: Consider expiring values after some fixed time for long-running
 #servers
 
-# TODO(kristijanburnik): Provide shared Stash support for WebSockets.
-
 class Stash(object):
-    """Key-value store for persisting data across HTTP/S requests.
+    """Key-value store for persisting data across HTTP/S and WS/S requests.
 
-    This data store is specifically designed for persisting data across
-    HTTP and HTTPS requests. The synchronization model is usually done by using
-    the SyncManager from the multiprocessing module.
+    This data store is specifically designed for persisting data across server
+    requests. The synchronization is achieved by using the BaseManager from
+    the multiprocessing module so different processes can acccess the same data.
 
-    Stash can be used interchangeably between HTTP and HTTPS requests as both
-    processes are accessing the same resource (e.g. a Manager.dict).
-    The WS and WSS servers are currently not supported.
+    Stash can be used interchangeably between HTTP, HTTPS, WS and WSS servers.
+    A thing to note about WS/S servers is that they require additional steps in
+    the handlers for accessing the same underlying shared data in the Stash.
+    This can usually be achieved by using load_env_config(). When using Stash
+    interchangeably between HTTP/S and WS/S request, the path part of the key
+    should be expliclitly specified if accessing the same key/value subset.
 
     The store has several unusual properties. Keys are of the form (path,
     uuid), where path is, by default, the path in the HTTP request and
@@ -118,7 +118,7 @@ class Stash(object):
         if internal_key in self.data:
             raise StashError("Tried to overwrite existing shared stash value "
                              "for key %s (old value was %s, new value is %s)" %
-                             (internal_key, self[str(internal_key)], value))
+                             (internal_key, self.data[str(internal_key)], value))
         else:
             self.data[internal_key] = value
 
@@ -130,7 +130,7 @@ class Stash(object):
                      the current request path)"""
         internal_key = self._wrap_key(key, path)
         value = self.data.get(internal_key, None)
-        if not value is None:
+        if value is not None:
             try:
                 self.data.pop(internal_key)
             except KeyError: