Integration tests for WebLite to Lo-Fi fallback

tools/chrome_proxy/webdriver/lite_page.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 LitePage(IntegrationTest):
+
+  # Checks that a Lite Page is served and that the ignore_preview_blacklist
+  # experiment is being used.
+  def testLitePage(self):
+    with TestDriver() as test_driver:
+      test_driver.AddChromeArg('--enable-spdy-proxy-auth')
+      test_driver.AddChromeArg('--data-reduction-proxy-lo-fi=always-on')
+      test_driver.AddChromeArg('--enable-data-reduction-proxy-lite-page')
+
+      test_driver.LoadURL('http://check.googlezip.net/test.html')
+
+      lite_page_responses = 0
+      for response in test_driver.GetHTTPResponses():
+        # Skip CSI requests when validating Lite Page headers. CSI requests
+        # aren't expected to have LoFi headers.
+        if '/csi?' in response.url:
+          continue
+        if response.url.startswith('data:'):
+          continue
+        self.assertIn('exp=ignore_preview_blacklist',
+          response.request_headers['chrome-proxy'])
+        if (self.checkLitePageResponse(response)):
+          lite_page_responses = lite_page_responses + 1
+
+      # Verify that a Lite Page response for the main frame was seen.
+      self.assertEqual(1, lite_page_responses)
+
+  # Checks that Lo-Fi images are used when the user is in the
+  # DataCompressionProxyLitePageFallback field trial and a Lite Page is not
+  # served.
+  def testLitePageFallback(self):
+    with TestDriver() as test_driver:
+      test_driver.AddChromeArg('--enable-spdy-proxy-auth')
+      test_driver.AddChromeArg('--data-reduction-proxy-lo-fi=always-on')

[tbansal1, 2017/03/03 21:17:56]

Can you add a comment that setting these two flags turns on the lite page
fallback mechanism.

Also, why not set the field trial instead of the flags to make it consistent
with the test below?

[megjablon, 2017/03/03 22:05:03]

Made it consistent with the test below.

+      test_driver.AddChromeArg('--enable-data-reduction-proxy-lite-page')
+
+      test_driver.LoadURL('http://check.googlezip.net/lite-page-fallback')
+
+      lite_page_requests = 0
+      lo_fi_responses = 0
+      for response in test_driver.GetHTTPResponses():
+        if not response.request_headers:
+          continue
+
+        cpat_request = response.request_headers['chrome-proxy-accept-transform']
+        if ('lite-page' in cpat_request):
+          lite_page_requests = lite_page_requests + 1
+          self.assertFalse(self.checkLitePageResponse(response))
+
+        if not response.url.endswith('png'):
+          continue
+
+        if (self.checkLoFiResponse(response, True)):
+          lo_fi_responses = lo_fi_responses + 1
+
+      # Verify that a Lite Page was requested and that the page fell back to
+      # Lo-Fi images.
+      self.assertEqual(1, lite_page_requests)
+      self.assertEqual(1, lo_fi_responses)
+
+  # Checks that Lo-Fi images are not used when the user is not in the
+  # DataCompressionProxyLitePageFallback field trial and a Lite Page is not
+  # served.
+  def testLitePageNoFallback(self):
+    with TestDriver() as test_driver:
+      test_driver.AddChromeArg('--enable-spdy-proxy-auth')
+      # Lite Pages must be enabled via the field trial because the Lite Page
+      # flag always falls back to Lo-Fi.
+      test_driver.AddChromeArg('--force-fieldtrials='
+                               'DataCompressionProxyLoFi/Enabled_Preview')
+      test_driver.AddChromeArg('--force-fieldtrial-params='
+                               'DataCompressionProxyLoFi.Enabled_Preview:'
+                               'effective_connection_type/4G')

[tbansal1, 2017/03/03 21:17:56]

I think it is safer to also force NQE to return ECT of say 2G.

--force-net-effective-connection-type=2g

This flag is not there in Chromium yet, but I will add code for it soon.

[megjablon, 2017/03/03 22:05:03]

Done.

+
+      test_driver.LoadURL('http://check.googlezip.net/lite-page-fallback')
+
+      lite_page_requests = 0
+      for response in test_driver.GetHTTPResponses():
+        if not response.request_headers:
+          continue
+
+        if ('chrome-proxy-accept-transform' in response.request_headers):
+          cpat_request = response.request_headers[
+                           'chrome-proxy-accept-transform']
+          if ('lite-page' in cpat_request):
+            lite_page_requests = lite_page_requests + 1
+            self.assertFalse(self.checkLitePageResponse(response))
+
+        if not response.url.endswith('png'):
+          continue
+
+        print response.url

[tbansal1, 2017/03/03 21:17:56]

Why print?

[megjablon, 2017/03/03 22:05:03]

Ah my bad, was using this when .png was getting lite page and forgot to remove
when it succeeded because it only prints when the test fails.

+
+        self.checkLoFiResponse(response, False)
+
+      # Verify that a Lite Page was requested and that the page fell back to
+      # Lo-Fi images.
+      self.assertEqual(1, lite_page_requests)
+
+if __name__ == '__main__':
+  IntegrationTest.RunAllTests()