Fix sorting of gRPCLB addresses when resolved via DNS

src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc

@@ -181,6 +181,12 @@ void grpc_ares_complete_request_locked(grpc_ares_request* r) {
     // TODO(apolcyn): allow c-ares to return a service config
     // with no addresses along side it
   }
+  if (r->balancer_addresses_out != nullptr) {
+    ServerAddressList* balancer_addresses = r->balancer_addresses_out->get();
+    if (balancer_addresses != nullptr) {
+      grpc_cares_wrapper_address_sorting_sort(r, balancer_addresses);
+    }
+  }
   grpc_core::ExecCtx::Run(DEBUG_LOCATION, r->on_done, r->error);
 }
 

test/cpp/naming/gen_build_yaml.py

@@ -44,6 +44,8 @@ def _resolver_test_cases(resolver_component_data):
                 target_name,
             'arg_names_and_values': [
                 ('target_name', target_name),
+                ('do_ordered_address_comparison',
+                 test_case['do_ordered_address_comparison']),
                 ('expected_addrs',
                  _build_expected_addrs_cmd_arg(test_case['expected_addrs'])),
                 ('expected_chosen_service_config',

test/cpp/naming/resolver_component_test.cc

@@ -87,6 +87,13 @@ using namespace google;
 using namespace gflags;
 
 DEFINE_string(target_name, "", "Target name to resolve.");
+DEFINE_string(do_ordered_address_comparison, "",
+              "Whether or not to compare resolved addresses to expected "
+              "addresses using an ordered comparison. This is useful for "
+              "testing certain behaviors that involve sorting of resolved "
+              "addresses. Note it would be better if this argument was a "
+              "bool flag, but it's a string for ease of invocation from "
+              "the generated python test runner.");
 DEFINE_string(expected_addrs, "",
               "List of expected backend or balancer addresses in the form "
               "'<ip0:port0>,<is_balancer0>;<ip1:port1>,<is_balancer1>;...'. "
@@ -484,8 +491,18 @@ class CheckingResultHandler : public ResultHandler {
               found_lb_addrs.size(), args->expected_addrs.size());
       abort();
     }
-    EXPECT_THAT(args->expected_addrs,
-                UnorderedElementsAreArray(found_lb_addrs));
+    if (FLAGS_do_ordered_address_comparison == "True") {
+      EXPECT_EQ(args->expected_addrs, found_lb_addrs);
+    } else if (FLAGS_do_ordered_address_comparison == "False") {
+      EXPECT_THAT(args->expected_addrs,
+                  UnorderedElementsAreArray(found_lb_addrs));
+    } else {
+      gpr_log(GPR_ERROR,
+              "Invalid for setting for --do_ordered_address_comparison. "
+              "Have %s, want True or False",
+              FLAGS_do_ordered_address_comparison.c_str());
+      GPR_ASSERT(0);
+    }
     const char* service_config_json =
         result.service_config == nullptr
             ? nullptr

test/cpp/naming/resolver_component_tests_runner.py

@@ -122,6 +122,7 @@ test_runner_log('Run test with target: %s' % 'no-srv-ipv4-single-target.resolver
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'no-srv-ipv4-single-target.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '5.5.5.5:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -138,6 +139,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-single-target.resolver-te
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-single-target.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:1234,True',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -154,6 +156,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-multi-target.resolver-tes
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-multi-target.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.5:1234,True;1.2.3.6:1234,True;1.2.3.7:1234,True',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -170,6 +173,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv6-single-target.resolver-te
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv6-single-target.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '[2607:f8b0:400a:801::1001]:1234,True',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -186,6 +190,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv6-multi-target.resolver-tes
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv6-multi-target.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '[2607:f8b0:400a:801::1002]:1234,True;[2607:f8b0:400a:801::1003]:1234,True;[2607:f8b0:400a:801::1004]:1234,True',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -202,6 +207,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-simple-service-config.res
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-simple-service-config.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:1234,True',
   '--expected_chosen_service_config', '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService"}],"waitForReady":true}]}',
   '--expected_service_config_error', '',
@@ -218,6 +224,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-no-srv-simple-service-config.
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-no-srv-simple-service-config.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"NoSrvSimpleService"}],"waitForReady":true}]}',
   '--expected_service_config_error', '',
@@ -234,6 +241,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-no-config-for-cpp.resolver-te
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-no-config-for-cpp.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -250,6 +258,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-cpp-config-has-zero-percentag
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-cpp-config-has-zero-percentage.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -266,6 +275,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-second-language-is-cpp.resolv
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-second-language-is-cpp.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"CppService"}],"waitForReady":true}]}',
   '--expected_service_config_error', '',
@@ -282,6 +292,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-config-with-percentages.resol
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-config-with-percentages.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"AlwaysPickedService"}],"waitForReady":true}]}',
   '--expected_service_config_error', '',
@@ -298,6 +309,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-target-has-backend-and-ba
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-target-has-backend-and-balancer.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:1234,True;1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -314,6 +326,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv6-target-has-backend-and-ba
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv6-target-has-backend-and-balancer.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '[2607:f8b0:400a:801::1002]:1234,True;[2607:f8b0:400a:801::1002]:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -330,6 +343,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-config-causing-fallback-to-tc
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-config-causing-fallback-to-tcp.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooTwo","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooThree","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFour","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFive","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooSix","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooSeven","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooEight","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooNine","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooTen","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooEleven","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooTwelve","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooThirteen","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFourteen","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFifteen","service":"SimpleService"}],"waitForReady":true}]}',
   '--expected_service_config_error', '',
@@ -346,6 +360,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-single-target-srv-disable
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-single-target-srv-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '2.3.4.5:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -362,6 +377,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-multi-target-srv-disabled
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-multi-target-srv-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '9.2.3.5:443,False;9.2.3.6:443,False;9.2.3.7:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -378,6 +394,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv6-single-target-srv-disable
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv6-single-target-srv-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '[2600::1001]:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -394,6 +411,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv6-multi-target-srv-disabled
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv6-multi-target-srv-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '[2600::1002]:443,False;[2600::1003]:443,False;[2600::1004]:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -410,6 +428,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-simple-service-config-srv
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-simple-service-config-srv-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '5.5.3.4:443,False',
   '--expected_chosen_service_config', '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService"}],"waitForReady":true}]}',
   '--expected_service_config_error', '',
@@ -426,6 +445,7 @@ test_runner_log('Run test with target: %s' % 'srv-ipv4-simple-service-config-txt
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'srv-ipv4-simple-service-config-txt-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:1234,True',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -442,6 +462,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-cpp-config-has-zero-percentag
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-cpp-config-has-zero-percentage-txt-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -458,6 +479,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-second-language-is-cpp-txt-di
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-second-language-is-cpp-txt-disabled.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -474,6 +496,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-svc_cfg_bad_json.resolver-tes
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-svc_cfg_bad_json.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', 'JSON parse error',
@@ -490,6 +513,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-svc_cfg_bad_client_language.r
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-svc_cfg_bad_client_language.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', 'field:clientLanguage error:should be of type array',
@@ -506,6 +530,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-svc_cfg_bad_percentage.resolv
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-svc_cfg_bad_percentage.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', 'field:percentage error:should be of type number',
@@ -522,6 +547,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-svc_cfg_bad_wait_for_ready.re
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-svc_cfg_bad_wait_for_ready.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', 'field:waitForReady error:Type should be true/false',
@@ -538,6 +564,7 @@ test_runner_log('Run test with target: %s' % 'no-srv-ipv4-single-target-inject-b
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'no-srv-ipv4-single-target-inject-broken-nameservers.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '5.5.5.5:443,False',
   '--expected_chosen_service_config', '',
   '--expected_service_config_error', '',
@@ -554,6 +581,7 @@ test_runner_log('Run test with target: %s' % 'ipv4-config-causing-fallback-to-tc
 current_test_subprocess = subprocess.Popen([
   args.test_bin_path,
   '--target_name', 'ipv4-config-causing-fallback-to-tcp-inject-broken-nameservers.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'False',
   '--expected_addrs', '1.2.3.4:443,False',
   '--expected_chosen_service_config', '{"loadBalancingPolicy":["round_robin"]}',
   '--expected_service_config_error', 'field:loadBalancingPolicy error:type should be string',
@@ -566,6 +594,23 @@ current_test_subprocess.communicate()
 if current_test_subprocess.returncode != 0:
   num_test_failures += 1
 
+test_runner_log('Run test with target: %s' % 'load-balanced-name-with-dualstack-balancer.resolver-tests-version-4.grpctestingexp.')
+current_test_subprocess = subprocess.Popen([
+  args.test_bin_path,
+  '--target_name', 'load-balanced-name-with-dualstack-balancer.resolver-tests-version-4.grpctestingexp.',
+  '--do_ordered_address_comparison', 'True',
+  '--expected_addrs', '[::1]:1234,True;[2002::1111]:1234,True',
+  '--expected_chosen_service_config', '',
+  '--expected_service_config_error', '',
+  '--expected_lb_policy', '',
+  '--enable_srv_queries', 'True',
+  '--enable_txt_queries', 'True',
+  '--inject_broken_nameserver_list', 'False',
+  '--local_dns_server_address', '127.0.0.1:%d' % args.dns_server_port])
+current_test_subprocess.communicate()
+if current_test_subprocess.returncode != 0:
+  num_test_failures += 1
+
 test_runner_log('now kill DNS server')
 dns_server_subprocess.kill()
 dns_server_subprocess.wait()

test/cpp/naming/resolver_test_record_groups.yaml

@@ -3,6 +3,7 @@ resolver_component_tests:
 # Tests for which we enable SRV queries
 - expected_addrs:
   - {address: '5.5.5.5:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -15,6 +16,7 @@ resolver_component_tests:
     - {TTL: '2100', data: 5.5.5.5, type: A}
 - expected_addrs:
   - {address: '1.2.3.4:1234', is_balancer: true}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -31,6 +33,7 @@ resolver_component_tests:
   - {address: '1.2.3.5:1234', is_balancer: true}
   - {address: '1.2.3.6:1234', is_balancer: true}
   - {address: '1.2.3.7:1234', is_balancer: true}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -47,6 +50,7 @@ resolver_component_tests:
     - {TTL: '2100', data: 1.2.3.7, type: A}
 - expected_addrs:
   - {address: '[2607:f8b0:400a:801::1001]:1234', is_balancer: true}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -63,6 +67,7 @@ resolver_component_tests:
   - {address: '[2607:f8b0:400a:801::1002]:1234', is_balancer: true}
   - {address: '[2607:f8b0:400a:801::1003]:1234', is_balancer: true}
   - {address: '[2607:f8b0:400a:801::1004]:1234', is_balancer: true}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -79,6 +84,7 @@ resolver_component_tests:
     - {TTL: '2100', data: '2607:f8b0:400a:801::1004', type: AAAA}
 - expected_addrs:
   - {address: '1.2.3.4:1234', is_balancer: true}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService"}],"waitForReady":true}]}'
   expected_service_config_error: null
   expected_lb_policy: round_robin
@@ -96,6 +102,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"NoSrvSimpleService"}],"waitForReady":true}]}'
   expected_service_config_error: null
   expected_lb_policy: round_robin
@@ -111,6 +118,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -126,6 +134,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -141,6 +150,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"CppService"}],"waitForReady":true}]}'
   expected_service_config_error: null
   expected_lb_policy: round_robin
@@ -156,6 +166,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"AlwaysPickedService"}],"waitForReady":true}]}'
   expected_service_config_error: null
   expected_lb_policy: round_robin
@@ -172,6 +183,7 @@ resolver_component_tests:
 - expected_addrs:
   - {address: '1.2.3.4:1234', is_balancer: true}
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -189,6 +201,7 @@ resolver_component_tests:
 - expected_addrs:
   - {address: '[2607:f8b0:400a:801::1002]:1234', is_balancer: true}
   - {address: '[2607:f8b0:400a:801::1002]:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -205,6 +218,7 @@ resolver_component_tests:
     - {TTL: '2100', data: '2607:f8b0:400a:801::1002', type: AAAA}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooTwo","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooThree","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFour","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFive","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooSix","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooSeven","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooEight","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooNine","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooTen","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooEleven","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooTwelve","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooThirteen","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFourteen","service":"SimpleService"}],"waitForReady":true},{"name":[{"method":"FooFifteen","service":"SimpleService"}],"waitForReady":true}]}'
   expected_service_config_error: null
   expected_lb_policy: null
@@ -221,6 +235,7 @@ resolver_component_tests:
 # Tests for which we don't enable SRV queries
 - expected_addrs:
   - {address: '2.3.4.5:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -239,6 +254,7 @@ resolver_component_tests:
   - {address: '9.2.3.5:443', is_balancer: false}
   - {address: '9.2.3.6:443', is_balancer: false}
   - {address: '9.2.3.7:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -259,6 +275,7 @@ resolver_component_tests:
     - {TTL: '2100', data: 9.2.3.7, type: A}
 - expected_addrs:
   - {address: '[2600::1001]:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -277,6 +294,7 @@ resolver_component_tests:
   - {address: '[2600::1002]:443', is_balancer: false}
   - {address: '[2600::1003]:443', is_balancer: false}
   - {address: '[2600::1004]:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -297,6 +315,7 @@ resolver_component_tests:
     - {TTL: '2100', data: '2600::1004', type: AAAA}
 - expected_addrs:
   - {address: '5.5.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService"}],"waitForReady":true}]}'
   expected_service_config_error: null
   expected_lb_policy: round_robin
@@ -316,6 +335,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:1234', is_balancer: true}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -333,6 +353,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -348,6 +369,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -363,6 +385,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: 'JSON parse error'
   expected_lb_policy: null
@@ -378,6 +401,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: 'field:clientLanguage error:should be of type array'
   expected_lb_policy: null
@@ -393,6 +417,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: 'field:percentage error:should be of type number'
   expected_lb_policy: null
@@ -408,6 +433,7 @@ resolver_component_tests:
       type: TXT}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: 'field:waitForReady error:Type should be true/false'
   expected_lb_policy: null
@@ -420,10 +446,11 @@ resolver_component_tests:
     - {TTL: '2100', data: 1.2.3.4, type: A}
     _grpc_config.ipv4-svc_cfg_bad_wait_for_ready:
     - {TTL: '2100', data: 'grpc_config=[{"serviceConfig":{"methodConfig":[{"name":[{"method":"Foo","service":"CppService"}],"waitForReady":"true"}]}}]',
-      type: TXT}      
+      type: TXT}
 # Tests for which we also exercise the resolver's ability to skip past a broken DNS server in its nameserver list
 - expected_addrs:
   - {address: '5.5.5.5:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: null
   expected_service_config_error: null
   expected_lb_policy: null
@@ -436,6 +463,7 @@ resolver_component_tests:
     - {TTL: '2100', data: 5.5.5.5, type: A}
 - expected_addrs:
   - {address: '1.2.3.4:443', is_balancer: false}
+  do_ordered_address_comparison: false
   expected_chosen_service_config: '{"loadBalancingPolicy":["round_robin"]}'
   expected_service_config_error: 'field:loadBalancingPolicy error:type should be string'
   expected_lb_policy: null
@@ -449,3 +477,26 @@ resolver_component_tests:
     _grpc_config.ipv4-config-causing-fallback-to-tcp-inject-broken-nameservers:
     - {TTL: '2100', data: 'grpc_config=[{"serviceConfig":{"loadBalancingPolicy":["round_robin"]}}]',
       type: TXT}
+# This tests that gRPCLB addresses are sorted properly per RFC 6724. Note
+# that the only assumption that this makes is that the machine that the
+# test runs on has a functioning IPv6 loopback (which by the RFC should
+# always be preferred). Note too that the ordering of the AAAA records
+# listed under the dualstack-balancer name is important in order to
+# actually test this sorting.
+- expected_addrs:
+  - {address: '[::1]:1234', is_balancer: true}
+  - {address: '[2002::1111]:1234', is_balancer: true}
+  do_ordered_address_comparison: true
+  expected_chosen_service_config: null
+  expected_service_config_error: null
+  expected_lb_policy: null
+  enable_srv_queries: true
+  enable_txt_queries: true
+  inject_broken_nameserver_list: false
+  record_to_resolve: load-balanced-name-with-dualstack-balancer
+  records:
+    _grpclb._tcp.load-balanced-name-with-dualstack-balancer:
+    - {TTL: '2100', data: 0 0 1234 dualstack-balancer, type: SRV}
+    dualstack-balancer:
+    - {TTL: '2100', data: '2002::1111', type: AAAA}
+    - {TTL: '2100', data: '::1', type: AAAA}