buildbucket: add monitoring using ts_mon

appengine/cr-buildbucket/test/metrics_test.py

 # Copyright 2015 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 datetime
 
 from google.appengine.ext import ndb
 import mock
 
 from components import metrics as metrics_component
@@ skipping 74 matching lines @@
       project_config_pb2.Bucket(name='x')
     ])
     self.mock(metrics, 'send_build_status_metric', mock.Mock())
 
     metrics.send_all_metrics()
 
     metrics.send_build_status_metric.assert_any_call(
       buf, 'x', metrics.METRIC_PENDING_BUILDS, model.BuildStatus.SCHEDULED)
     metrics.send_build_status_metric.assert_any_call(
       buf, 'x', metrics.METRIC_RUNNING_BUILDS, model.BuildStatus.STARTED)
+
+  def test_fields_for(self):
+    self.assertEqual(
+      metrics.fields_for(
+        model.Build(
+          bucket='master.x',
+          tags=['builder:release', 'user_agent:cq', 'something:else']),
+        result='SUCCESS'),
+      {
+        'bucket': 'master.x',
+        'builder': 'release',
+        'user_agent': 'cq',
+        'result': 'SUCCESS',
+      }
+    )