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/admin_servlets.py b/chrome/common/extensions/docs/server2/admin_servlets.py
new file mode 100644
index 0000000000000000000000000000000000000000..7990761e02d1cb9928580904ccd657a0d13b4a44
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+++ b/chrome/common/extensions/docs/server2/admin_servlets.py
@@ -0,0 +1,111 @@
+# 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.
+
+from appengine_wrappers import taskqueue
+from commit_tracker import CommitTracker
+from future import All
+from object_store_creator import ObjectStoreCreator
+from refresh_tracker import RefreshTracker
+from servlet import Servlet, Response
+
+
+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
+  timeout of a non-taskqueue request. For example, you might query
+
+  /_enqueue/_refresh/content_providers/cr-native-client?commit=123ff65468dcafff0
+
+  which will enqueue a task (/_refresh/content_providers/cr-native-client) to
+  refresh the NaCl documentation cache for commit 123ff65468dcafff0.
+
+  Access to this servlet should always be restricted to administrative users.
+  '''
+  def __init__(self, request):
+    Servlet.__init__(self, request)
+
+  def Get(self):
+    queue = taskqueue.Queue()
+    queue.add(taskqueue.Task(url='/%s' % self._request.path,
+                             params=self._request.arguments))
+    return Response.Ok('Task enqueued.')
+
+
+class QueryCommitServlet(Servlet):
+  '''Provides read access to the commit ID cache within the server. For example:
+
+  /_query_commit/master
+
+  will return the commit ID stored under the commit key "master" within the
+  commit cache. Currently "master" is the only named commit we cache, and it
+  corresponds to the commit ID whose data currently populates the data cache
+  used by live instances.
+  '''
+  def __init__(self, request):
+    Servlet.__init__(self, request)
+
+  def Get(self):
+    object_store_creator = ObjectStoreCreator(start_empty=False)
+    commit_tracker = CommitTracker(object_store_creator)
+
+    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 DumpRefreshServlet(Servlet):
+  def __init__(self, request):
+    Servlet.__init__(self, request)
+
+  def Get(self):
+    object_store_creator = ObjectStoreCreator(start_empty=False)
+    refresh_tracker = RefreshTracker(object_store_creator)
+    commit_id = self._request.path
+    work_order = refresh_tracker._GetWorkOrder(commit_id).Get()
+    task_names = ['%s@%s' % (commit_id, task) for task in work_order.tasks]
+    completions = refresh_tracker._task_completions.GetMulti(task_names).Get()
+    missing = []
+    for task in task_names:
+      if task not in completions:
+        missing.append(task)
+    response = 'Missing:<br>%s' % ''.join('%s<br>' % task for task in missing)
+    return Response.Ok(response)
+
+class ResetCommitServlet(Servlet):
+  '''Writes a new commit ID to the commit cache. For example:
+
+  /_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.
+  '''
+
+  class Delegate(object):
+    def CreateCommitTracker(self):
+      return CommitTracker(ObjectStoreCreator(start_empty=False))
+
+  def __init__(self, request, delegate=Delegate()):
+    Servlet.__init__(self, request)
+    self._delegate = delegate
+
+  def Get(self):
+    commit_tracker = self._delegate.CreateCommitTracker()
+    commit_name, commit_id = self._request.path.split('/', 1)
+    history = commit_tracker.GetHistory(commit_name).Get()
+    if not any(entry.commit_id == commit_id for entry in history):
+      return Response.BadRequest('Commit %s not cached.' % commit_id)
+    commit_tracker.Set(commit_name, commit_id).Get()
+    return Response.Ok('Commit "%s" updated to %s' % (commit_name, commit_id))
+