gae_ts_mon: instrument Cloud Endpoint methods

infra_libs/ts_mon/common/http_metrics.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.
 
 from infra_libs.ts_mon.common import metrics
 
 
 # Extending HTTP status codes to client-side errors and timeouts.
 STATUS_OK = 200
 STATUS_ERROR = 901
@@ skipping 16 matching lines @@
     'http/server_request_bytes',
     description='Bytes received per http request (body only).')
 server_response_bytes = metrics.CumulativeDistributionMetric(
     'http/server_response_bytes',
     description='Bytes sent per http request (content only).')
 server_durations = metrics.CumulativeDistributionMetric('http/server_durations',
     description='Time elapsed between receiving a request and sending a'
                 ' response (including parsing) in milliseconds.')
 server_response_status = metrics.CounterMetric('http/server_response_status',
     description='Number of responses sent by HTTP status code.')
+
+
+def update_http_server_metrics(endpoint_name, response_status_code, elapsed_ms,
+                               request_size=None, response_size=None,
+                               user_agent=None):
+  fields = {'status': response_status_code, 'name': endpoint_name,
+            'is_robot': False}
+  if user_agent is not None:
+    # We must not log user agents, but we can store whether or not the
+    # user agent string indicates that the requester was a Google bot.
+    fields['is_robot'] = (
+        'GoogleBot' in user_agent or
+        'GoogleSecurityScanner' in user_agent or
+        user_agent == 'B3M/prober')
+
+  server_durations.add(elapsed_ms, fields=fields)
+  server_response_status.increment(fields=fields)
+  if request_size is not None:
+    server_request_bytes.add(request_size, fields=fields)
+  if response_size is not None:
+    server_response_bytes.add(response_size, fields=fields)