1 //
2 //
3 // Copyright 2017 gRPC authors.
4 //
5 // Licensed under the Apache License, Version 2.0 (the "License");
6 // you may not use this file except in compliance with the License.
7 // You may obtain a copy of the License at
8 //
9 // http://www.apache.org/licenses/LICENSE-2.0
10 //
11 // Unless required by applicable law or agreed to in writing, software
12 // distributed under the License is distributed on an "AS IS" BASIS,
13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 // See the License for the specific language governing permissions and
15 // limitations under the License.
16 //
17 //
18
19 #include <gmock/gmock.h>
20 #include <grpc/grpc.h>
21 #include <grpc/support/alloc.h>
22 #include <grpc/support/string_util.h>
23 #include <grpc/support/time.h>
24 #include <grpcpp/channel.h>
25 #include <grpcpp/client_context.h>
26 #include <grpcpp/create_channel.h>
27 #include <grpcpp/impl/sync.h>
28 #include <grpcpp/server.h>
29 #include <grpcpp/server_builder.h>
30
31 #include <atomic>
32 #include <memory>
33 #include <mutex>
34 #include <random>
35 #include <sstream>
36 #include <thread>
37
38 #include "src/core/lib/address_utils/parse_address.h"
39 #include "src/core/lib/channel/channel_args.h"
40 #include "src/core/lib/iomgr/sockaddr.h"
41 #include "src/core/load_balancing/grpclb/grpclb_balancer_addresses.h"
42 #include "src/core/resolver/endpoint_addresses.h"
43 #include "src/core/resolver/fake/fake_resolver.h"
44 #include "src/core/service_config/service_config_impl.h"
45 #include "src/core/util/crash.h"
46 #include "src/core/util/ref_counted_ptr.h"
47 #include "src/core/util/thd.h"
48 #include "test/core/test_util/port.h"
49 #include "test/core/test_util/test_config.h"
50
51 namespace {
52
TryConnectAndDestroy()53 void TryConnectAndDestroy() {
54 auto response_generator =
55 grpc_core::MakeRefCounted<grpc_core::FakeResolverResponseGenerator>();
56 // Return a grpclb address with an IP address on the IPv6 discard prefix
57 // (https://tools.ietf.org/html/rfc6666). This is important because
58 // the behavior we want in this test is for a TCP connect attempt to "freeze",
59 // i.e. we want to send SYN, and then *not* receive SYN-ACK or RST.
60 // The precise behavior is dependant on the test runtime environment though,
61 // since connect() attempts on this address may unfortunately result in
62 // "network unreachable" errors in some test runtime environments.
63 absl::StatusOr<grpc_core::URI> lb_uri =
64 grpc_core::URI::Parse("ipv6:[0100::1234]:443");
65 ASSERT_TRUE(lb_uri.ok());
66 grpc_resolved_address address;
67 ASSERT_TRUE(grpc_parse_uri(*lb_uri, &address));
68 grpc_core::EndpointAddressesList addresses;
69 addresses.emplace_back(address, grpc_core::ChannelArgs());
70 grpc_core::Resolver::Result lb_address_result;
71 lb_address_result.service_config = grpc_core::ServiceConfigImpl::Create(
72 grpc_core::ChannelArgs(), "{\"loadBalancingConfig\":[{\"grpclb\":{}}]}");
73 ASSERT_TRUE(lb_address_result.service_config.ok())
74 << lb_address_result.service_config.status();
75 lb_address_result.args = grpc_core::SetGrpcLbBalancerAddresses(
76 grpc_core::ChannelArgs(), addresses);
77 response_generator->SetResponseAsync(lb_address_result);
78 grpc::ChannelArguments args;
79 args.SetPointer(GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR,
80 response_generator.get());
81 // Explicitly set the connect deadline to the same amount of
82 // time as the WaitForConnected time. The goal is to get the
83 // connect timeout code to run at about the same time as when
84 // the channel gets destroyed, to try to reproduce a race.
85 args.SetInt("grpc.testing.fixed_reconnect_backoff_ms",
86 grpc_test_slowdown_factor() * 100);
87 std::ostringstream uri;
88 uri << "fake:///servername_not_used";
89 auto channel = grpc::CreateCustomChannel(
90 uri.str(), grpc::InsecureChannelCredentials(), args);
91 // Start connecting, and give some time for the TCP connection attempt to the
92 // unreachable balancer to begin. The connection should never become ready
93 // because the LB we're trying to connect to is unreachable.
94 channel->GetState(true /* try_to_connect */);
95 ASSERT_FALSE(
96 channel->WaitForConnected(grpc_timeout_milliseconds_to_deadline(100)));
97 ASSERT_EQ("grpclb", channel->GetLoadBalancingPolicyName());
98 channel.reset();
99 };
100
TEST(DestroyGrpclbChannelWithActiveConnectStressTest,LoopTryConnectAndDestroy)101 TEST(DestroyGrpclbChannelWithActiveConnectStressTest,
102 LoopTryConnectAndDestroy) {
103 grpc_init();
104 std::vector<std::unique_ptr<std::thread>> threads;
105 const int kNumThreads = 10;
106 threads.reserve(kNumThreads);
107 for (int i = 0; i < kNumThreads; i++) {
108 threads.emplace_back(new std::thread(TryConnectAndDestroy));
109 }
110 for (size_t i = 0; i < threads.size(); i++) {
111 threads[i]->join();
112 }
113 grpc_shutdown();
114 }
115
116 } // namespace
117
main(int argc,char ** argv)118 int main(int argc, char** argv) {
119 grpc::testing::TestEnvironment env(&argc, argv);
120 ::testing::InitGoogleTest(&argc, argv);
121 auto result = RUN_ALL_TESTS();
122 return result;
123 }
124