First cut of chrome-proxy (data reduction proxy) measurements.

tools/perf/metrics/chrome_proxy.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 telemetry.page import page_measurement
+from metrics import network
+
+
+class ChromeProxyMetricException(page_measurement.MeasurementFailure):
+  pass
+
+
+CHROME_PROXY_VIA_HEADER = 'Chrome-Compression-Proxy'
+CHROME_PROXY_VIA_HEADER_DEPRECATED = '1.1 Chrome Compression Proxy'
+
+
+class ChromeProxyResponse(network.HTTPResponse):
+  """ Represents an HTTP response from a timeleine event."""
+  def __init__(self, event):
+    super(ChromeProxyResponse, self).__init__(event)
+
+  def ShouldHaveChromeProxyViaHeader(self):
+    resp = self.response
+    # Ignore https and data url
+    if resp.url.startswith('https') or resp.url.startswith('data:'):
+      return False
+    # Ignore 304 Not Modified.
+    if resp.status == 304:
+      return False
+    return True
+
+  def HasChromeProxyViaHeader(self):
+    via_header = self.response.GetHeader('Via')
+    if not via_header:
+      return False
+    vias = [v.strip(' ') for v in via_header.split(',')]
+    # The Via header is valid if it is the old format or the new format
+    # with 4-character version prefix, for example,
+    # "1.1 Chrome-Compression-Proxy".
+    return (CHROME_PROXY_VIA_HEADER_DEPRECATED in vias or
+            any(v[4:] == CHROME_PROXY_VIA_HEADER for v in vias))
+
+  def IsValidByViaHeader(self):
+    return (not self.ShouldHaveChromeProxyViaHeader() or
+            self.HasChromeProxyViaHeader())
+
+  def IsSafebrowsingResponse(self):
+    if (self.response.status == 307 and
+        self.response.GetHeader('X-Malware-Url') == '1' and
+        self.IsValidByViaHeader() and
+        self.response.GetHeader('Location') == self.response.url):
+      return True
+    return False
+
+
+class ChromeProxyMetric(network.NetworkMetric):
+  """A Chrome proxy timeline metric."""
+
+  def __init__(self):
+    super(ChromeProxyMetric, self).__init__()
+    self.compute_data_saving = True
+
+  def SetEvents(self, events):
+    """Used for unittest."""
+    self._events = events
+
+  def ResponseFromEvent(self, event):
+    return ChromeProxyResponse(event)
+
+  def AddResults(self, tab, results):
+    raise NotImplementedError
+
+  def AddResultsForDataSaving(self, tab, results):
+    resources_via_proxy = 0
+    resources_from_cache = 0
+    resources_direct = 0
+
+    super(ChromeProxyMetric, self).AddResults(tab, results)
+    for resp in self.IterResponses(tab):
+      if resp.response.served_from_cache:
+        resources_from_cache += 1
+      if resp.HasChromeProxyViaHeader():
+        resources_via_proxy += 1
+      else:
+        resources_direct += 1
+
+    results.Add('resources_via_proxy', 'count', resources_via_proxy)
+    results.Add('resources_from_cache', 'count', resources_from_cache)
+    results.Add('resources_direct', 'count', resources_direct)
+
+  def AddResultsForHeaderValidation(self, tab, results):
+    via_count = 0
+    for resp in self.IterResponses(tab):
+      if resp.IsValidByViaHeader():
+        via_count += 1
+      else:
+        r = resp.response
+        raise ChromeProxyMetricException, (
+            '%s: Via header (%s) is not valid (refer=%s, status=%d)' % (
+                r.url, r.GetHeader('Via'), r.GetHeader('Referer'), r.status))
+    results.Add('checked_via_header', 'count', via_count)
+
+  def AddResultsForBypass(self, tab, results):
+    bypass_count = 0
+    for resp in self.IterResponses(tab):
+      if resp.HasChromeProxyViaHeader():
+        r = resp.response
+        raise ChromeProxyMetricException, (
+            '%s: Should not have Via header (%s) (refer=%s, status=%d)' % (
+                r.url, r.GetHeader('Via'), r.GetHeader('Referer'), r.status))
+      bypass_count += 1
+    results.Add('bypass', 'count', bypass_count)
+
+  def AddResultsForSafebrowsing(self, tab, results):
+    count = 0
+    safebrowsing_count = 0
+    for resp in self.IterResponses(tab):
+      count += 1
+      if resp.IsSafebrowsingResponse():
+        safebrowsing_count += 1
+      else:
+        r = resp.response
+        raise ChromeProxyMetricException, (
+            '%s: Not a valid safe browsing response.\n'
+            'Reponse: status=(%d, %s)\nHeaders:\n %s' % (
+                r.url, r.status, r.status_text, r.headers))
+    if count == safebrowsing_count:
+      results.Add('safebrowsing', 'boolean', True)
+    else:
+      raise ChromeProxyMetricException, (
+          'Safebrowsing failed (count=%d, safebrowsing_count=%d)\n' % (
+              count, safebrowsing_count))