Integration test of Data Saver block-once directive

tools/chrome_proxy/webdriver/bypass.py

 # Copyright 2017 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 common
 from common import TestDriver
 from common import IntegrationTest
 
 
 class Bypass(IntegrationTest):
 
+  # Ensure Chrome does not use Data Saver for block-once, but does use Data
+  # Saver for a subsequent request.
+  def testBlockOnce(self):
+    with TestDriver() as t:
+      t.AddChromeArg('--enable-spdy-proxy-auth')
+      t.LoadURL('http://check.googlezip.net/blocksingle/')
+      responses = t.GetHTTPResponses()
+      self.assertEqual(2, len(responses))
+      for response in responses:
+        if response.url == "http://check.googlezip.net/image.png":
+          self.assertHasChromeProxyViaHeader(response)
+        else:
+          self.assertNotHasChromeProxyViaHeader(response)
+
   # Ensure Chrome does not use Data Saver for block=0, which uses the default
   # proxy retry delay.
   def testBypass(self):
     with TestDriver() as t:
       t.AddChromeArg('--enable-spdy-proxy-auth')
       t.LoadURL('http://check.googlezip.net/block/')
       for response in t.GetHTTPResponses():
         self.assertNotHasChromeProxyViaHeader(response)
 
       # Load another page and check that Data Saver is not used.
@@ skipping 22 matching lines @@
           same_origin_requests = same_origin_requests + 1
         else:
           self.assertNotHasChromeProxyViaHeader(response)
           cors_requests = cors_requests + 1
       # Verify that both CORS and same origin requests were seen.
       self.assertNotEqual(0, same_origin_requests)
       self.assertNotEqual(0, cors_requests)
 
 if __name__ == '__main__':
   IntegrationTest.RunAllTests()