Use httplib's host property instead of urllib3's _dns_host (#659)

Author: tpyo

contrib/opencensus-ext-httplib/opencensus/ext/httplib/trace.py

@@ -64,7 +64,7 @@ def call(self, method, url, body, headers, *args, **kwargs):
         _tracer = execution_context.get_opencensus_tracer()
         blacklist_hostnames = execution_context.get_opencensus_attr(
             'blacklist_hostnames')
-        dest_url = '{}:{}'.format(self._dns_host, self.port)
+        dest_url = '{}:{}'.format(self.host, self.port)
         if utils.disable_tracing_hostname(dest_url, blacklist_hostnames):
             return request_func(self, method, url, body,
                                 headers, *args, **kwargs)

contrib/opencensus-ext-httplib/tests/test_httplib_trace.py

@@ -150,10 +150,10 @@ def test_wrap_httplib_request_blacklist_nok(self):
         wrapped = trace.wrap_httplib_request(mock_request_func)
 
         mock_self = mock.Mock()
-        mock_self._dns_host = 'localhost'
+        mock_self.host = 'localhost'
         mock_self.port = '8080'
         method = 'GET'
-        url = 'http://{}:{}'.format(mock_self._dns_host, mock_self.port)
+        url = 'http://{}:{}'.format(mock_self.host, mock_self.port)
         body = None
         headers = {}