tools/chrome_proxy/common/chrome_proxy_metrics.py

   1 # Copyright 2014 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import logging
   6 import time
   7
   8 from common import network_metrics
   9 from telemetry.page import page_test
  10 from telemetry.value import scalar
  11
  12
  13 CHROME_PROXY_VIA_HEADER = 'Chrome-Compression-Proxy'
  14
  15
  16 class ChromeProxyMetricException(page_test.MeasurementFailure):
  17   pass
  18
  19
  20 class ChromeProxyResponse(network_metrics.HTTPResponse):
  21   """ Represents an HTTP response from a timeline event."""
  22   def __init__(self, event):
  23     super(ChromeProxyResponse, self).__init__(event)
  24
  25   def ShouldHaveChromeProxyViaHeader(self):
  26     resp = self.response
  27     # Ignore https and data url
  28     if resp.url.startswith('https') or resp.url.startswith('data:'):
  29       return False
  30     # Ignore 304 Not Modified and cache hit.
  31     if resp.status == 304 or resp.served_from_cache:
  32       return False
  33     # Ignore invalid responses that don't have any header. Log a warning.
  34     if not resp.headers:
  35       logging.warning('response for %s does not any have header '
  36                       '(refer=%s, status=%s)',
  37                       resp.url, resp.GetHeader('Referer'), resp.status)
  38       return False
  39     return True
  40
  41   def HasChromeProxyViaHeader(self):
  42     via_header = self.response.GetHeader('Via')
  43     if not via_header:
  44       return False
  45     vias = [v.strip(' ') for v in via_header.split(',')]
  46     # The Via header is valid if it has a 4-character version prefix followed by
  47     # the proxy name, for example, "1.1 Chrome-Compression-Proxy".
  48     return any(v[4:] == CHROME_PROXY_VIA_HEADER for v in vias)
  49
  50   def HasExtraViaHeader(self, extra_header):
  51     via_header = self.response.GetHeader('Via')
  52     if not via_header:
  53       return False
  54     vias = [v.strip(' ') for v in via_header.split(',')]
  55     return any(v == extra_header for v in vias)
  56
  57   def IsValidByViaHeader(self):
  58     return (not self.ShouldHaveChromeProxyViaHeader() or
  59             self.HasChromeProxyViaHeader())
  60
  61   def GetChromeProxyClientType(self):
  62     """Get the client type directive from the Chrome-Proxy request header.
  63
  64     Returns:
  65         The client type directive from the Chrome-Proxy request header for the
  66         request that lead to this response. For example, if the request header
  67         "Chrome-Proxy: c=android" is present, then this method would return
  68         "android". Returns None if no client type directive is present.
  69     """
  70     if 'Chrome-Proxy' not in self.response.request_headers:
  71       return None
  72
  73     chrome_proxy_request_header = self.response.request_headers['Chrome-Proxy']
  74     values = [v.strip() for v in chrome_proxy_request_header.split(',')]
  75     for value in values:
  76       kvp = value.split('=', 1)
  77       if len(kvp) == 2 and kvp[0].strip() == 'c':
  78         return kvp[1].strip()
  79     return None
  80
  81   def HasChromeProxyLoFiRequest(self):
  82     if 'Chrome-Proxy' not in self.response.request_headers:
  83       return False
  84     chrome_proxy_request_header = self.response.request_headers['Chrome-Proxy']
  85     values = [v.strip() for v in chrome_proxy_request_header.split(',')]
  86     return any(v == "q=low" for v in values)
  87
  88   def HasChromeProxyLoFiResponse(self):
  89     chrome_proxy_response_header = self.response.GetHeader('Chrome-Proxy')
  90     if not chrome_proxy_response_header:
  91       return False
  92     values = [v.strip() for v in chrome_proxy_response_header.split(',')]
  93     return any(v == "q=low" for v in values)