Docserver: Add commit history and _reset_commit servlet

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

Index: chrome/common/extensions/docs/server2/admin_servlets.py
diff --git a/chrome/common/extensions/docs/server2/handler.py b/chrome/common/extensions/docs/server2/admin_servlets.py
similarity index 51%
copy from chrome/common/extensions/docs/server2/handler.py
copy to chrome/common/extensions/docs/server2/admin_servlets.py
index a0e044e753aab96ad34bc124736999020b42f372..b569f5d8ae318091c025a45caa7f677ad24ed098 100644
--- a/chrome/common/extensions/docs/server2/handler.py
+++ b/chrome/common/extensions/docs/server2/admin_servlets.py
@@ -1,24 +1,15 @@
-# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Copyright 2014 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 time
-
 from appengine_wrappers import taskqueue
 from commit_tracker import CommitTracker
-from cron_servlet import CronServlet
-from instance_servlet import InstanceServlet
+from future import All
 from object_store_creator import ObjectStoreCreator
-from patch_servlet import PatchServlet
-from refresh_servlet import RefreshServlet
-from servlet import Servlet, Request, Response
-from test_servlet import TestServlet
-
-
-_DEFAULT_SERVLET = InstanceServlet.GetConstructor()
+from servlet import Servlet, Response
 
 
-class _EnqueueServlet(Servlet):
+class EnqueueServlet(Servlet):
   '''This Servlet can be used to manually enqueue tasks on the default
   taskqueue. Useful for when an admin wants to manually force a specific
   DataSource refresh, but the refresh operation takes longer than the 60 sec
@@ -41,7 +32,7 @@ class _EnqueueServlet(Servlet):
     return Response.Ok('Task enqueued.')
 
 
-class _QueryCommitServlet(Servlet):
+class QueryCommitServlet(Servlet):
   '''Provides read access to the commit ID cache within the server. For example:
 
   /_query_commit/master
@@ -57,36 +48,40 @@ class _QueryCommitServlet(Servlet):
   def Get(self):
     object_store_creator = ObjectStoreCreator(start_empty=False)
     commit_tracker = CommitTracker(object_store_creator)
-    return Response.Ok(commit_tracker.Get(self._request.path).Get())
 
+    def generate_response(result):
+      commit_id, history = result
+      history_log = ''.join('%s: %s<br>' % (entry.datetime, entry.commit_id)
+                            for entry in reversed(history))
+      response = 'Current commit: %s<br><br>Most recent commits:<br>%s' % (
+          commit_id, history_log)
+      return response
+
+    commit_name = self._request.path
+    id_future = commit_tracker.Get(commit_name)
+    history_future = commit_tracker.GetHistory(commit_name)
+    return Response.Ok(
+        All((id_future, history_future)).Then(generate_response).Get())
+
+
+class ResetCommitServlet(Servlet):
+  '''Writes a new commit ID to the commit cache. For example:
 
-_SERVLETS = {
-  'cron': CronServlet,
-  'enqueue': _EnqueueServlet,
-  'patch': PatchServlet,
-  'query_commit': _QueryCommitServlet,
-  'refresh': RefreshServlet,
-  'test': TestServlet,
-}
+  /_reset_commit/master/123456
 
+  will reset the 'master' commit ID to '123456'. The provided commit MUST be
+  in the named commit's recent history or it will be ignored.
+  '''
+  def __init__(self, request):
+    Servlet.__init__(self, request)
 
-class Handler(Servlet):
   def Get(self):
-    path = self._request.path
-
-    if path.startswith('_'):
-      servlet_path = path[1:]
-      if not '/' in servlet_path:
-        servlet_path += '/'
-      servlet_name, servlet_path = servlet_path.split('/', 1)
-      servlet = _SERVLETS.get(servlet_name)
-      if servlet is None:
-        return Response.NotFound('"%s" servlet not found' %  servlet_path)
-    else:
-      servlet_path = path
-      servlet = _DEFAULT_SERVLET
-
-    return servlet(Request(servlet_path,
-                           self._request.host,
-                           self._request.headers,
-                           self._request.arguments)).Get()
+    object_store_creator = ObjectStoreCreator(start_empty=False)
+    commit_tracker = CommitTracker(object_store_creator)
+    commit_name, commit_id = self._request.path.split('/')

[not at google - send to devlin, 2014/11/19 19:32:41]

You might want to use .split('/', 1) so that this doesn't crash if there are
more than 1 '/' tokens.

You might also consider using one of the utilities in path.py. I think that has
something which does that, and either way, they make nice assertions about valid
paths.

[Ken Rockot(use gerrit already), 2015/02/02 23:57:44]

Done.

+    history = commit_tracker.GetHistory(commit_name).Get()
+    if not any(entry.commit_id == commit_id for entry in history):
+      return Response.NotFound('Commit %s not found.' % commit_id)

[not at google - send to devlin, 2014/11/19 19:32:41]

Nit, but I don't think 404 is actually the right error code here. Maybe 400 (bad
request)? Or something else you find in
http://en.wikipedia.org/wiki/List_of_HTTP_status_codes#4xx_Client_Error which
sounds right.

Of course, you should add a BadRequest (or whatever) utility to Response if you
go with that.

[Ken Rockot(use gerrit already), 2015/02/02 23:57:44]

Done. 400 seems like the only reasonable option.

+    commit_tracker.Set(commit_name, commit_id).Get()
+    return Response.Ok('Commit "%s" updated to %s' % (commit_name, commit_id))
+