1# Copyright 2019 The gRPC Authors 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# http://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12# See the License for the specific language governing permissions and 13# limitations under the License. 14"""Tests for an actual dns resolution.""" 15 16import logging 17import unittest 18 19import grpc 20 21from tests.unit import test_common 22from tests.unit.framework.common import test_constants 23 24_SERVICE_NAME = "test" 25_METHOD = "METHOD" 26_REQUEST = b"\x00\x00\x00" 27_RESPONSE = _REQUEST 28 29 30_METHOD_HANDLERS = { 31 _METHOD: grpc.unary_unary_rpc_method_handler( 32 lambda request, unused_context: request, 33 ) 34} 35 36 37class DNSResolverTest(unittest.TestCase): 38 def setUp(self): 39 self._server = test_common.test_server() 40 self._server.add_registered_method_handlers( 41 _SERVICE_NAME, _METHOD_HANDLERS 42 ) 43 self._port = self._server.add_insecure_port("[::]:0") 44 self._server.start() 45 46 def tearDown(self): 47 self._server.stop(None) 48 49 def test_connect_loopback(self): 50 # NOTE(https://github.com/grpc/grpc/issues/18422) 51 # In short, Gevent + C-Ares = Segfault. The C-Ares driver is not 52 # supported by custom io manager like "gevent" 53 # NOTE(b/201064791): use loopback46.unittest.grpc.io since 54 # it returns the expected responses even when DNS64 dns servers 55 # are used on the test worker (and for purposes of this 56 # test the use of loopback4 vs loopback46 makes no difference). 57 with grpc.insecure_channel( 58 "loopback46.unittest.grpc.io:%d" % self._port 59 ) as channel: 60 self.assertEqual( 61 channel.unary_unary( 62 grpc._common.fully_qualified_method(_SERVICE_NAME, _METHOD), 63 _registered_method=True, 64 )( 65 _REQUEST, 66 timeout=10, 67 ), 68 _RESPONSE, 69 ) 70 71 72if __name__ == "__main__": 73 logging.basicConfig() 74 unittest.main(verbosity=2) 75