/* * * Copyright 2016 gRPC authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h" #include "src/core/ext/filters/client_channel/subchannel_index.h" #include "src/core/lib/backoff/backoff.h" #include "src/core/lib/gpr/env.h" #include "src/core/lib/gprpp/debug_location.h" #include "src/core/lib/gprpp/ref_counted_ptr.h" #include "src/proto/grpc/testing/echo.grpc.pb.h" #include "test/core/util/port.h" #include "test/core/util/test_config.h" #include "test/cpp/end2end/test_service_impl.h" #include using grpc::testing::EchoRequest; using grpc::testing::EchoResponse; using std::chrono::system_clock; // defined in tcp_client_posix.c extern void (*grpc_tcp_client_connect_impl)( grpc_closure* closure, grpc_endpoint** ep, grpc_pollset_set* interested_parties, const grpc_channel_args* channel_args, const grpc_resolved_address* addr, grpc_millis deadline); const auto original_tcp_connect_fn = grpc_tcp_client_connect_impl; namespace grpc { namespace testing { namespace { gpr_atm g_connection_delay_ms; void tcp_client_connect_with_delay(grpc_closure* closure, grpc_endpoint** ep, grpc_pollset_set* interested_parties, const grpc_channel_args* channel_args, const grpc_resolved_address* addr, grpc_millis deadline) { const int delay_ms = gpr_atm_acq_load(&g_connection_delay_ms); if (delay_ms > 0) { gpr_sleep_until(grpc_timeout_milliseconds_to_deadline(delay_ms)); } original_tcp_connect_fn(closure, ep, interested_parties, channel_args, addr, deadline + delay_ms); } // Subclass of TestServiceImpl that increments a request counter for // every call to the Echo RPC. class MyTestServiceImpl : public TestServiceImpl { public: MyTestServiceImpl() : request_count_(0) {} Status Echo(ServerContext* context, const EchoRequest* request, EchoResponse* response) override { { std::unique_lock lock(mu_); ++request_count_; } return TestServiceImpl::Echo(context, request, response); } int request_count() { std::unique_lock lock(mu_); return request_count_; } void ResetCounters() { std::unique_lock lock(mu_); request_count_ = 0; } private: std::mutex mu_; int request_count_; }; class ClientLbEnd2endTest : public ::testing::Test { protected: ClientLbEnd2endTest() : server_host_("localhost"), kRequestMessage_("Live long and prosper.") { // Make the backup poller poll very frequently in order to pick up // updates from all the subchannels's FDs. gpr_setenv("GRPC_CLIENT_CHANNEL_BACKUP_POLL_INTERVAL_MS", "1"); } void SetUp() override { response_generator_ = grpc_core::MakeRefCounted(); } void TearDown() override { for (size_t i = 0; i < servers_.size(); ++i) { servers_[i]->Shutdown(); } } void StartServers(size_t num_servers, std::vector ports = std::vector()) { for (size_t i = 0; i < num_servers; ++i) { int port = 0; if (ports.size() == num_servers) port = ports[i]; servers_.emplace_back(new ServerData(server_host_, port)); } } void SetNextResolution(const std::vector& ports) { grpc_core::ExecCtx exec_ctx; grpc_lb_addresses* addresses = grpc_lb_addresses_create(ports.size(), nullptr); for (size_t i = 0; i < ports.size(); ++i) { char* lb_uri_str; gpr_asprintf(&lb_uri_str, "ipv4:127.0.0.1:%d", ports[i]); grpc_uri* lb_uri = grpc_uri_parse(lb_uri_str, true); GPR_ASSERT(lb_uri != nullptr); grpc_lb_addresses_set_address_from_uri(addresses, i, lb_uri, false /* is balancer */, "" /* balancer name */, nullptr); grpc_uri_destroy(lb_uri); gpr_free(lb_uri_str); } grpc_arg fake_addresses = grpc_lb_addresses_create_channel_arg(addresses); grpc_channel_args fake_result = {1, &fake_addresses}; response_generator_->SetResponse(&fake_result); grpc_lb_addresses_destroy(addresses); } void SetNextResolutionUponError(const std::vector& ports) { grpc_core::ExecCtx exec_ctx; grpc_lb_addresses* addresses = grpc_lb_addresses_create(ports.size(), nullptr); for (size_t i = 0; i < ports.size(); ++i) { char* lb_uri_str; gpr_asprintf(&lb_uri_str, "ipv4:127.0.0.1:%d", ports[i]); grpc_uri* lb_uri = grpc_uri_parse(lb_uri_str, true); GPR_ASSERT(lb_uri != nullptr); grpc_lb_addresses_set_address_from_uri(addresses, i, lb_uri, false /* is balancer */, "" /* balancer name */, nullptr); grpc_uri_destroy(lb_uri); gpr_free(lb_uri_str); } grpc_arg fake_addresses = grpc_lb_addresses_create_channel_arg(addresses); grpc_channel_args fake_result = {1, &fake_addresses}; response_generator_->SetReresolutionResponse(&fake_result); grpc_lb_addresses_destroy(addresses); } std::vector GetServersPorts() { std::vector ports; for (const auto& server : servers_) ports.push_back(server->port_); return ports; } std::unique_ptr BuildStub( const std::shared_ptr& channel) { return grpc::testing::EchoTestService::NewStub(channel); } std::shared_ptr BuildChannel( const grpc::string& lb_policy_name, ChannelArguments args = ChannelArguments()) { if (lb_policy_name.size() > 0) { args.SetLoadBalancingPolicyName(lb_policy_name); } // else, default to pick first args.SetPointer(GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR, response_generator_.get()); return CreateCustomChannel("fake:///", InsecureChannelCredentials(), args); } bool SendRpc( const std::unique_ptr& stub, EchoResponse* response = nullptr, int timeout_ms = 1000) { const bool local_response = (response == nullptr); if (local_response) response = new EchoResponse; EchoRequest request; request.set_message(kRequestMessage_); ClientContext context; context.set_deadline(grpc_timeout_milliseconds_to_deadline(timeout_ms)); Status status = stub->Echo(&context, request, response); if (local_response) delete response; return status.ok(); } void CheckRpcSendOk( const std::unique_ptr& stub, const grpc_core::DebugLocation& location) { EchoResponse response; const bool success = SendRpc(stub, &response); if (!success) abort(); ASSERT_TRUE(success) << "From " << location.file() << ":" << location.line(); ASSERT_EQ(response.message(), kRequestMessage_) << "From " << location.file() << ":" << location.line(); } void CheckRpcSendFailure( const std::unique_ptr& stub) { const bool success = SendRpc(stub); EXPECT_FALSE(success); } struct ServerData { int port_; std::unique_ptr server_; MyTestServiceImpl service_; std::unique_ptr thread_; bool server_ready_ = false; explicit ServerData(const grpc::string& server_host, int port = 0) { port_ = port > 0 ? port : grpc_pick_unused_port_or_die(); gpr_log(GPR_INFO, "starting server on port %d", port_); std::mutex mu; std::unique_lock lock(mu); std::condition_variable cond; thread_.reset(new std::thread( std::bind(&ServerData::Start, this, server_host, &mu, &cond))); cond.wait(lock, [this] { return server_ready_; }); server_ready_ = false; gpr_log(GPR_INFO, "server startup complete"); } void Start(const grpc::string& server_host, std::mutex* mu, std::condition_variable* cond) { std::ostringstream server_address; server_address << server_host << ":" << port_; ServerBuilder builder; builder.AddListeningPort(server_address.str(), InsecureServerCredentials()); builder.RegisterService(&service_); server_ = builder.BuildAndStart(); std::lock_guard lock(*mu); server_ready_ = true; cond->notify_one(); } void Shutdown(bool join = true) { server_->Shutdown(grpc_timeout_milliseconds_to_deadline(0)); if (join) thread_->join(); } }; void ResetCounters() { for (const auto& server : servers_) server->service_.ResetCounters(); } void WaitForServer( const std::unique_ptr& stub, size_t server_idx, const grpc_core::DebugLocation& location) { do { CheckRpcSendOk(stub, location); } while (servers_[server_idx]->service_.request_count() == 0); ResetCounters(); } bool SeenAllServers() { for (const auto& server : servers_) { if (server->service_.request_count() == 0) return false; } return true; } // Updates \a connection_order by appending to it the index of the newly // connected server. Must be called after every single RPC. void UpdateConnectionOrder( const std::vector>& servers, std::vector* connection_order) { for (size_t i = 0; i < servers.size(); ++i) { if (servers[i]->service_.request_count() == 1) { // Was the server index known? If not, update connection_order. const auto it = std::find(connection_order->begin(), connection_order->end(), i); if (it == connection_order->end()) { connection_order->push_back(i); return; } } } } const grpc::string server_host_; std::unique_ptr stub_; std::vector> servers_; grpc_core::RefCountedPtr response_generator_; const grpc::string kRequestMessage_; }; TEST_F(ClientLbEnd2endTest, PickFirst) { // Start servers and send one RPC per server. const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel(""); // test that pick first is the default. auto stub = BuildStub(channel); std::vector ports; for (size_t i = 0; i < servers_.size(); ++i) { ports.emplace_back(servers_[i]->port_); } SetNextResolution(ports); for (size_t i = 0; i < servers_.size(); ++i) { CheckRpcSendOk(stub, DEBUG_LOCATION); } // All requests should have gone to a single server. bool found = false; for (size_t i = 0; i < servers_.size(); ++i) { const int request_count = servers_[i]->service_.request_count(); if (request_count == kNumServers) { found = true; } else { EXPECT_EQ(0, request_count); } } EXPECT_TRUE(found); // Check LB policy name for the channel. EXPECT_EQ("pick_first", channel->GetLoadBalancingPolicyName()); } TEST_F(ClientLbEnd2endTest, PickFirstBackOffInitialReconnect) { ChannelArguments args; constexpr int kInitialBackOffMs = 100; args.SetInt(GRPC_ARG_INITIAL_RECONNECT_BACKOFF_MS, kInitialBackOffMs); const std::vector ports = {grpc_pick_unused_port_or_die()}; const gpr_timespec t0 = gpr_now(GPR_CLOCK_MONOTONIC); auto channel = BuildChannel("pick_first", args); auto stub = BuildStub(channel); SetNextResolution(ports); // The channel won't become connected (there's no server). ASSERT_FALSE(channel->WaitForConnected( grpc_timeout_milliseconds_to_deadline(kInitialBackOffMs * 2))); // Bring up a server on the chosen port. StartServers(1, ports); // Now it will. ASSERT_TRUE(channel->WaitForConnected( grpc_timeout_milliseconds_to_deadline(kInitialBackOffMs * 2))); const gpr_timespec t1 = gpr_now(GPR_CLOCK_MONOTONIC); const grpc_millis waited_ms = gpr_time_to_millis(gpr_time_sub(t1, t0)); gpr_log(GPR_DEBUG, "Waited %ld milliseconds", waited_ms); // We should have waited at least kInitialBackOffMs. We substract one to // account for test and precision accuracy drift. EXPECT_GE(waited_ms, kInitialBackOffMs - 1); // But not much more. EXPECT_GT( gpr_time_cmp( grpc_timeout_milliseconds_to_deadline(kInitialBackOffMs * 1.10), t1), 0); } TEST_F(ClientLbEnd2endTest, PickFirstBackOffMinReconnect) { ChannelArguments args; constexpr int kMinReconnectBackOffMs = 1000; args.SetInt(GRPC_ARG_MIN_RECONNECT_BACKOFF_MS, kMinReconnectBackOffMs); const std::vector ports = {grpc_pick_unused_port_or_die()}; auto channel = BuildChannel("pick_first", args); auto stub = BuildStub(channel); SetNextResolution(ports); // Make connection delay a 10% longer than it's willing to in order to make // sure we are hitting the codepath that waits for the min reconnect backoff. gpr_atm_rel_store(&g_connection_delay_ms, kMinReconnectBackOffMs * 1.10); grpc_tcp_client_connect_impl = tcp_client_connect_with_delay; const gpr_timespec t0 = gpr_now(GPR_CLOCK_MONOTONIC); channel->WaitForConnected( grpc_timeout_milliseconds_to_deadline(kMinReconnectBackOffMs * 2)); const gpr_timespec t1 = gpr_now(GPR_CLOCK_MONOTONIC); const grpc_millis waited_ms = gpr_time_to_millis(gpr_time_sub(t1, t0)); gpr_log(GPR_DEBUG, "Waited %ld ms", waited_ms); // We should have waited at least kMinReconnectBackOffMs. We substract one to // account for test and precision accuracy drift. EXPECT_GE(waited_ms, kMinReconnectBackOffMs - 1); gpr_atm_rel_store(&g_connection_delay_ms, 0); } TEST_F(ClientLbEnd2endTest, PickFirstUpdates) { // Start servers and send one RPC per server. const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel("pick_first"); auto stub = BuildStub(channel); std::vector ports; // Perform one RPC against the first server. ports.emplace_back(servers_[0]->port_); SetNextResolution(ports); gpr_log(GPR_INFO, "****** SET [0] *******"); CheckRpcSendOk(stub, DEBUG_LOCATION); EXPECT_EQ(servers_[0]->service_.request_count(), 1); // An empty update will result in the channel going into TRANSIENT_FAILURE. ports.clear(); SetNextResolution(ports); gpr_log(GPR_INFO, "****** SET none *******"); grpc_connectivity_state channel_state; do { channel_state = channel->GetState(true /* try to connect */); } while (channel_state == GRPC_CHANNEL_READY); GPR_ASSERT(channel_state != GRPC_CHANNEL_READY); servers_[0]->service_.ResetCounters(); // Next update introduces servers_[1], making the channel recover. ports.clear(); ports.emplace_back(servers_[1]->port_); SetNextResolution(ports); gpr_log(GPR_INFO, "****** SET [1] *******"); WaitForServer(stub, 1, DEBUG_LOCATION); EXPECT_EQ(servers_[0]->service_.request_count(), 0); // And again for servers_[2] ports.clear(); ports.emplace_back(servers_[2]->port_); SetNextResolution(ports); gpr_log(GPR_INFO, "****** SET [2] *******"); WaitForServer(stub, 2, DEBUG_LOCATION); EXPECT_EQ(servers_[0]->service_.request_count(), 0); EXPECT_EQ(servers_[1]->service_.request_count(), 0); // Check LB policy name for the channel. EXPECT_EQ("pick_first", channel->GetLoadBalancingPolicyName()); } TEST_F(ClientLbEnd2endTest, PickFirstUpdateSuperset) { // Start servers and send one RPC per server. const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel("pick_first"); auto stub = BuildStub(channel); std::vector ports; // Perform one RPC against the first server. ports.emplace_back(servers_[0]->port_); SetNextResolution(ports); gpr_log(GPR_INFO, "****** SET [0] *******"); CheckRpcSendOk(stub, DEBUG_LOCATION); EXPECT_EQ(servers_[0]->service_.request_count(), 1); servers_[0]->service_.ResetCounters(); // Send and superset update ports.clear(); ports.emplace_back(servers_[1]->port_); ports.emplace_back(servers_[0]->port_); SetNextResolution(ports); gpr_log(GPR_INFO, "****** SET superset *******"); CheckRpcSendOk(stub, DEBUG_LOCATION); // We stick to the previously connected server. WaitForServer(stub, 0, DEBUG_LOCATION); EXPECT_EQ(0, servers_[1]->service_.request_count()); // Check LB policy name for the channel. EXPECT_EQ("pick_first", channel->GetLoadBalancingPolicyName()); } TEST_F(ClientLbEnd2endTest, PickFirstManyUpdates) { // Start servers and send one RPC per server. const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel("pick_first"); auto stub = BuildStub(channel); std::vector ports; for (size_t i = 0; i < servers_.size(); ++i) { ports.emplace_back(servers_[i]->port_); } for (const bool force_creation : {true, false}) { grpc_subchannel_index_test_only_set_force_creation(force_creation); gpr_log(GPR_INFO, "Force subchannel creation: %d", force_creation); for (size_t i = 0; i < 1000; ++i) { std::shuffle(ports.begin(), ports.end(), std::mt19937(std::random_device()())); SetNextResolution(ports); if (i % 10 == 0) CheckRpcSendOk(stub, DEBUG_LOCATION); } } // Check LB policy name for the channel. EXPECT_EQ("pick_first", channel->GetLoadBalancingPolicyName()); } TEST_F(ClientLbEnd2endTest, RoundRobin) { // Start servers and send one RPC per server. const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel("round_robin"); auto stub = BuildStub(channel); std::vector ports; for (const auto& server : servers_) { ports.emplace_back(server->port_); } SetNextResolution(ports); // Wait until all backends are ready. do { CheckRpcSendOk(stub, DEBUG_LOCATION); } while (!SeenAllServers()); ResetCounters(); // "Sync" to the end of the list. Next sequence of picks will start at the // first server (index 0). WaitForServer(stub, servers_.size() - 1, DEBUG_LOCATION); std::vector connection_order; for (size_t i = 0; i < servers_.size(); ++i) { CheckRpcSendOk(stub, DEBUG_LOCATION); UpdateConnectionOrder(servers_, &connection_order); } // Backends should be iterated over in the order in which the addresses were // given. const auto expected = std::vector{0, 1, 2}; EXPECT_EQ(expected, connection_order); // Check LB policy name for the channel. EXPECT_EQ("round_robin", channel->GetLoadBalancingPolicyName()); } TEST_F(ClientLbEnd2endTest, RoundRobinUpdates) { // Start servers and send one RPC per server. const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel("round_robin"); auto stub = BuildStub(channel); std::vector ports; // Start with a single server. ports.emplace_back(servers_[0]->port_); SetNextResolution(ports); WaitForServer(stub, 0, DEBUG_LOCATION); // Send RPCs. They should all go servers_[0] for (size_t i = 0; i < 10; ++i) CheckRpcSendOk(stub, DEBUG_LOCATION); EXPECT_EQ(10, servers_[0]->service_.request_count()); EXPECT_EQ(0, servers_[1]->service_.request_count()); EXPECT_EQ(0, servers_[2]->service_.request_count()); servers_[0]->service_.ResetCounters(); // And now for the second server. ports.clear(); ports.emplace_back(servers_[1]->port_); SetNextResolution(ports); // Wait until update has been processed, as signaled by the second backend // receiving a request. EXPECT_EQ(0, servers_[1]->service_.request_count()); WaitForServer(stub, 1, DEBUG_LOCATION); for (size_t i = 0; i < 10; ++i) CheckRpcSendOk(stub, DEBUG_LOCATION); EXPECT_EQ(0, servers_[0]->service_.request_count()); EXPECT_EQ(10, servers_[1]->service_.request_count()); EXPECT_EQ(0, servers_[2]->service_.request_count()); servers_[1]->service_.ResetCounters(); // ... and for the last server. ports.clear(); ports.emplace_back(servers_[2]->port_); SetNextResolution(ports); WaitForServer(stub, 2, DEBUG_LOCATION); for (size_t i = 0; i < 10; ++i) CheckRpcSendOk(stub, DEBUG_LOCATION); EXPECT_EQ(0, servers_[0]->service_.request_count()); EXPECT_EQ(0, servers_[1]->service_.request_count()); EXPECT_EQ(10, servers_[2]->service_.request_count()); servers_[2]->service_.ResetCounters(); // Back to all servers. ports.clear(); ports.emplace_back(servers_[0]->port_); ports.emplace_back(servers_[1]->port_); ports.emplace_back(servers_[2]->port_); SetNextResolution(ports); WaitForServer(stub, 0, DEBUG_LOCATION); WaitForServer(stub, 1, DEBUG_LOCATION); WaitForServer(stub, 2, DEBUG_LOCATION); // Send three RPCs, one per server. for (size_t i = 0; i < 3; ++i) CheckRpcSendOk(stub, DEBUG_LOCATION); EXPECT_EQ(1, servers_[0]->service_.request_count()); EXPECT_EQ(1, servers_[1]->service_.request_count()); EXPECT_EQ(1, servers_[2]->service_.request_count()); // An empty update will result in the channel going into TRANSIENT_FAILURE. ports.clear(); SetNextResolution(ports); grpc_connectivity_state channel_state; do { channel_state = channel->GetState(true /* try to connect */); } while (channel_state == GRPC_CHANNEL_READY); GPR_ASSERT(channel_state != GRPC_CHANNEL_READY); servers_[0]->service_.ResetCounters(); // Next update introduces servers_[1], making the channel recover. ports.clear(); ports.emplace_back(servers_[1]->port_); SetNextResolution(ports); WaitForServer(stub, 1, DEBUG_LOCATION); channel_state = channel->GetState(false /* try to connect */); GPR_ASSERT(channel_state == GRPC_CHANNEL_READY); // Check LB policy name for the channel. EXPECT_EQ("round_robin", channel->GetLoadBalancingPolicyName()); } TEST_F(ClientLbEnd2endTest, RoundRobinUpdateInError) { const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel("round_robin"); auto stub = BuildStub(channel); std::vector ports; // Start with a single server. ports.emplace_back(servers_[0]->port_); SetNextResolution(ports); WaitForServer(stub, 0, DEBUG_LOCATION); // Send RPCs. They should all go to servers_[0] for (size_t i = 0; i < 10; ++i) SendRpc(stub); EXPECT_EQ(10, servers_[0]->service_.request_count()); EXPECT_EQ(0, servers_[1]->service_.request_count()); EXPECT_EQ(0, servers_[2]->service_.request_count()); servers_[0]->service_.ResetCounters(); // Shutdown one of the servers to be sent in the update. servers_[1]->Shutdown(false); ports.emplace_back(servers_[1]->port_); ports.emplace_back(servers_[2]->port_); SetNextResolution(ports); WaitForServer(stub, 0, DEBUG_LOCATION); WaitForServer(stub, 2, DEBUG_LOCATION); // Send three RPCs, one per server. for (size_t i = 0; i < kNumServers; ++i) SendRpc(stub); // The server in shutdown shouldn't receive any. EXPECT_EQ(0, servers_[1]->service_.request_count()); } TEST_F(ClientLbEnd2endTest, RoundRobinManyUpdates) { // Start servers and send one RPC per server. const int kNumServers = 3; StartServers(kNumServers); auto channel = BuildChannel("round_robin"); auto stub = BuildStub(channel); std::vector ports; for (size_t i = 0; i < servers_.size(); ++i) { ports.emplace_back(servers_[i]->port_); } for (size_t i = 0; i < 1000; ++i) { std::shuffle(ports.begin(), ports.end(), std::mt19937(std::random_device()())); SetNextResolution(ports); if (i % 10 == 0) CheckRpcSendOk(stub, DEBUG_LOCATION); } // Check LB policy name for the channel. EXPECT_EQ("round_robin", channel->GetLoadBalancingPolicyName()); } TEST_F(ClientLbEnd2endTest, RoundRobinConcurrentUpdates) { // TODO(dgq): replicate the way internal testing exercises the concurrent // update provisions of RR. } TEST_F(ClientLbEnd2endTest, RoundRobinReresolve) { // Start servers and send one RPC per server. const int kNumServers = 3; std::vector first_ports; std::vector second_ports; for (int i = 0; i < kNumServers; ++i) { first_ports.push_back(grpc_pick_unused_port_or_die()); } for (int i = 0; i < kNumServers; ++i) { second_ports.push_back(grpc_pick_unused_port_or_die()); } StartServers(kNumServers, first_ports); auto channel = BuildChannel("round_robin"); auto stub = BuildStub(channel); SetNextResolution(first_ports); // Send a number of RPCs, which succeed. for (size_t i = 0; i < 100; ++i) { CheckRpcSendOk(stub, DEBUG_LOCATION); } // Kill all servers gpr_log(GPR_INFO, "****** ABOUT TO KILL SERVERS *******"); for (size_t i = 0; i < servers_.size(); ++i) { servers_[i]->Shutdown(false); } gpr_log(GPR_INFO, "****** SERVERS KILLED *******"); gpr_log(GPR_INFO, "****** SENDING DOOMED REQUESTS *******"); // Client requests should fail. Send enough to tickle all subchannels. for (size_t i = 0; i < servers_.size(); ++i) CheckRpcSendFailure(stub); gpr_log(GPR_INFO, "****** DOOMED REQUESTS SENT *******"); // Bring servers back up on a different set of ports. We need to do this to be // sure that the eventual success is *not* due to subchannel reconnection // attempts and that an actual re-resolution has happened as a result of the // RR policy going into transient failure when all its subchannels become // unavailable (in transient failure as well). gpr_log(GPR_INFO, "****** RESTARTING SERVERS *******"); StartServers(kNumServers, second_ports); // Don't notify of the update. Wait for the LB policy's re-resolution to // "pull" the new ports. SetNextResolutionUponError(second_ports); gpr_log(GPR_INFO, "****** SERVERS RESTARTED *******"); gpr_log(GPR_INFO, "****** SENDING REQUEST TO SUCCEED *******"); // Client request should eventually (but still fairly soon) succeed. const gpr_timespec deadline = grpc_timeout_seconds_to_deadline(5); gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC); while (gpr_time_cmp(deadline, now) > 0) { if (SendRpc(stub)) break; now = gpr_now(GPR_CLOCK_MONOTONIC); } GPR_ASSERT(gpr_time_cmp(deadline, now) > 0); } TEST_F(ClientLbEnd2endTest, RoundRobinSingleReconnect) { const int kNumServers = 3; StartServers(kNumServers); const auto ports = GetServersPorts(); auto channel = BuildChannel("round_robin"); auto stub = BuildStub(channel); SetNextResolution(ports); for (size_t i = 0; i < kNumServers; ++i) WaitForServer(stub, i, DEBUG_LOCATION); for (size_t i = 0; i < servers_.size(); ++i) { CheckRpcSendOk(stub, DEBUG_LOCATION); EXPECT_EQ(1, servers_[i]->service_.request_count()) << "for backend #" << i; } // One request should have gone to each server. for (size_t i = 0; i < servers_.size(); ++i) { EXPECT_EQ(1, servers_[i]->service_.request_count()); } const auto pre_death = servers_[0]->service_.request_count(); // Kill the first server. servers_[0]->Shutdown(true); // Client request still succeed. May need retrying if RR had returned a pick // before noticing the change in the server's connectivity. while (!SendRpc(stub)) { ; // Retry until success. } gpr_log(GPR_INFO, "------------------------------------------------------"); // Send a bunch of RPCs that should succeed. for (int i = 0; i < 10 * kNumServers; ++i) { CheckRpcSendOk(stub, DEBUG_LOCATION); } const auto post_death = servers_[0]->service_.request_count(); // No requests have gone to the deceased server. EXPECT_EQ(pre_death, post_death); // Bring the first server back up. servers_[0].reset(new ServerData(server_host_, ports[0])); // Requests should start arriving at the first server either right away (if // the server managed to start before the RR policy retried the subchannel) or // after the subchannel retry delay otherwise (RR's subchannel retried before // the server was fully back up). WaitForServer(stub, 0, DEBUG_LOCATION); } } // namespace } // namespace testing } // namespace grpc int main(int argc, char** argv) { ::testing::InitGoogleTest(&argc, argv); grpc_test_init(argc, argv); grpc_init(); const auto result = RUN_ALL_TESTS(); grpc_shutdown(); return result; }