Reland of "[telemetry] Wire TsProxy through telemetry's network stack."

telemetry/telemetry/internal/forwarders/do_nothing_forwarder_unittest.py

Index: telemetry/telemetry/internal/forwarders/do_nothing_forwarder_unittest.py
diff --git a/telemetry/telemetry/internal/forwarders/do_nothing_forwarder_unittest.py b/telemetry/telemetry/internal/forwarders/do_nothing_forwarder_unittest.py
index 51ebe05d73521b02ce19cc8b6207ed8f73c4d8f9..6477161eb8dddf90c96cb57d563be850e89d5849 100644
--- a/telemetry/telemetry/internal/forwarders/do_nothing_forwarder_unittest.py
+++ b/telemetry/telemetry/internal/forwarders/do_nothing_forwarder_unittest.py
@@ -28,21 +28,44 @@
 
 
 class CheckPortPairsTest(unittest.TestCase):
-  def testBasicCheck(self):
-    port_pair = forwarders.PortPair(80, 80)
-    f = TestDoNothingForwarder(port_pair)
+  def testChecksOnlyHttpHttps(self):
+    port_pairs = forwarders.PortPairs(
+        http=forwarders.PortPair(80, 80),
+        https=forwarders.PortPair(443, 443),
+        dns=forwarders.PortPair(53, 53))
+    f = TestDoNothingForwarder(port_pairs)
     expected_connected_addresses = [
         ('127.0.0.1', 80),
+        ('127.0.0.1', 443),
+        # Port 53 is skipped because it is UDP and does not support connections.
+        ]
+    self.assertEqual(expected_connected_addresses, f.connected_addresses)
+
+  def testNoDnsStillChecksHttpHttps(self):
+    port_pairs = forwarders.PortPairs(
+        http=forwarders.PortPair(5566, 5566),
+        https=forwarders.PortPair(7788, 7788),
+        dns=None)
+    f = TestDoNothingForwarder(port_pairs)
+    expected_connected_addresses = [
+        ('127.0.0.1', 5566),
+        ('127.0.0.1', 7788),
         ]
     self.assertEqual(expected_connected_addresses, f.connected_addresses)
 
   def testPortMismatchRaisesPortsMismatchError(self):
     # The do_nothing_forward cannot forward from one port to another.
-    port_pair = forwarders.PortPair(80, 81)
+    port_pairs = forwarders.PortPairs(
+        http=forwarders.PortPair(80, 80),
+        https=forwarders.PortPair(8443, 443),
+        dns=None)
     with self.assertRaises(do_nothing_forwarder.PortsMismatchError):
-      TestDoNothingForwarder(port_pair)
+      TestDoNothingForwarder(port_pairs)
 
   def testConnectionTimeoutRaisesConnectionError(self):
-    port_pair = forwarders.PortPair(80, 80)
+    port_pairs = forwarders.PortPairs(
+        http=forwarders.PortPair(80, 80),
+        https=forwarders.PortPair(8443, 443),
+        dns=None)
     with self.assertRaises(do_nothing_forwarder.ConnectionError):
-      TestErrorDoNothingForwarder(port_pair)
+      TestErrorDoNothingForwarder(port_pairs)