Load only a few flakes on the index page and inline link to load more

appengine/chromium_try_flakes/handlers/index.py

 # 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 google.appengine.datastore.datastore_query import Cursor
 from google.appengine.ext import ndb
 from google.appengine.ext.webapp import template
 
 from model.flake import Flake
 from status.util import is_last_hour
 from status.util import is_last_day
 from status.util import is_last_week
 from status.util import is_last_month
 
 import datetime
 import logging
 import time
 import webapp2
 
 
+MAX_OCCURRENCES_PER_FLAKE_ON_INDEX_PAGE = 4
+
+
 def filterNone(elements):
   return [e for e in elements if e is not None]
 
 def FlakeSortFunction(s):  # pragma: no cover
   return s.builder + str(time.mktime(s.time_finished.timetuple()))
 
 def GetFilteredOccurences(flake, time_formatter,
                           filter_function):  # pragma: no cover
-  occurrences = filterNone(ndb.get_multi(flake.occurrences))
+  occurrences = filterNone(ndb.get_multi(
+    flake.occurrences[-MAX_OCCURRENCES_PER_FLAKE_ON_INDEX_PAGE:]))
 
   failure_run_keys = []
   patchsets_keys = []
   for o in occurrences:
     failure_run_keys.append(o.failure_run)
     patchsets_keys.append(o.failure_run.parent())
 
   failure_runs = filterNone(ndb.get_multi(failure_run_keys))
   patchsets = filterNone(ndb.get_multi(patchsets_keys))
 
@@ skipping 52 matching lines @@
       time_format = '%H:%M:%S'
     else:
       time_format = '%Y-%m-%d %H:%M:%S'
 
     def time_formatter(t):
       return t.strftime(time_format)
 
     for f in flakes:
       f.filtered_occurrences = GetFilteredOccurences(
           f, time_formatter, filter_by_range)
+      if len(f.occurrences) > MAX_OCCURRENCES_PER_FLAKE_ON_INDEX_PAGE:
+        f.more_occurrences = True
 
     values = {
       'range': time_range,
       'flakes': flakes,
       'more': more,
       'cursor': next_cursor.urlsafe() if next_cursor else '',
     }
     self.response.write(template.render('templates/index.html', values))