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grpc/test/cpp/end2end/grpclb_end2end_test.cc

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/*
*
* Copyright 2017 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 <memory>
#include <mutex>
#include <set>
#include <sstream>
#include <thread>
#include <grpc/grpc.h>
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/string_util.h>
#include <grpc/support/time.h>
#include <grpcpp/channel.h>
#include <grpcpp/client_context.h>
#include <grpcpp/create_channel.h>
#include <grpcpp/server.h>
#include <grpcpp/server_builder.h>
#include "src/core/ext/filters/client_channel/parse_address.h"
#include "src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h"
#include "src/core/ext/filters/client_channel/server_address.h"
#include "src/core/lib/gpr/env.h"
#include "src/core/lib/gprpp/ref_counted_ptr.h"
#include "src/core/lib/iomgr/sockaddr.h"
#include "src/core/lib/security/credentials/fake/fake_credentials.h"
#include "src/cpp/client/secure_credentials.h"
#include "src/cpp/server/secure_server_credentials.h"
#include "test/core/util/port.h"
#include "test/core/util/test_config.h"
#include "test/cpp/end2end/test_service_impl.h"
#include "src/proto/grpc/lb/v1/load_balancer.grpc.pb.h"
#include "src/proto/grpc/testing/echo.grpc.pb.h"
#include <gmock/gmock.h>
#include <gtest/gtest.h>
// TODO(dgq): Other scenarios in need of testing:
// - Send a serverlist with faulty ip:port addresses (port > 2^16, etc).
// - Test reception of invalid serverlist
// - Test pinging
// - Test against a non-LB server.
// - Random LB server closing the stream unexpectedly.
// - Test using DNS-resolvable names (localhost?)
// - Test handling of creation of faulty RR instance by having the LB return a
// serverlist with non-existent backends after having initially returned a
// valid one.
//
// Findings from end to end testing to be covered here:
// - Handling of LB servers restart, including reconnection after backing-off
// retries.
// - Destruction of load balanced channel (and therefore of grpclb instance)
// while:
// 1) the internal LB call is still active. This should work by virtue
// of the weak reference the LB call holds. The call should be terminated as
// part of the grpclb shutdown process.
// 2) the retry timer is active. Again, the weak reference it holds should
// prevent a premature call to \a glb_destroy.
// - Restart of backend servers with no changes to serverlist. This exercises
// the RR handover mechanism.
using std::chrono::system_clock;
using grpc::lb::v1::LoadBalanceRequest;
using grpc::lb::v1::LoadBalanceResponse;
using grpc::lb::v1::LoadBalancer;
namespace grpc {
namespace testing {
namespace {
template <typename ServiceType>
class CountedService : public ServiceType {
public:
size_t request_count() {
std::unique_lock<std::mutex> lock(mu_);
return request_count_;
}
size_t response_count() {
std::unique_lock<std::mutex> lock(mu_);
return response_count_;
}
void IncreaseResponseCount() {
std::unique_lock<std::mutex> lock(mu_);
++response_count_;
}
void IncreaseRequestCount() {
std::unique_lock<std::mutex> lock(mu_);
++request_count_;
}
void ResetCounters() {
std::unique_lock<std::mutex> lock(mu_);
request_count_ = 0;
response_count_ = 0;
}
protected:
std::mutex mu_;
private:
size_t request_count_ = 0;
size_t response_count_ = 0;
};
using BackendService = CountedService<TestServiceImpl>;
using BalancerService = CountedService<LoadBalancer::Service>;
const char g_kCallCredsMdKey[] = "Balancer should not ...";
const char g_kCallCredsMdValue[] = "... receive me";
class BackendServiceImpl : public BackendService {
public:
BackendServiceImpl() {}
Status Echo(ServerContext* context, const EchoRequest* request,
EchoResponse* response) override {
// Backend should receive the call credentials metadata.
auto call_credentials_entry =
context->client_metadata().find(g_kCallCredsMdKey);
EXPECT_NE(call_credentials_entry, context->client_metadata().end());
if (call_credentials_entry != context->client_metadata().end()) {
EXPECT_EQ(call_credentials_entry->second, g_kCallCredsMdValue);
}
IncreaseRequestCount();
const auto status = TestServiceImpl::Echo(context, request, response);
IncreaseResponseCount();
AddClient(context->peer());
return status;
}
// Returns true on its first invocation, false otherwise.
bool Shutdown() {
std::unique_lock<std::mutex> lock(mu_);
const bool prev = !shutdown_;
shutdown_ = true;
gpr_log(GPR_INFO, "Backend: shut down");
return prev;
}
std::set<grpc::string> clients() {
std::unique_lock<std::mutex> lock(clients_mu_);
return clients_;
}
private:
void AddClient(const grpc::string& client) {
std::unique_lock<std::mutex> lock(clients_mu_);
clients_.insert(client);
}
std::mutex mu_;
bool shutdown_ = false;
std::mutex clients_mu_;
std::set<grpc::string> clients_;
};
grpc::string Ip4ToPackedString(const char* ip_str) {
struct in_addr ip4;
GPR_ASSERT(inet_pton(AF_INET, ip_str, &ip4) == 1);
return grpc::string(reinterpret_cast<const char*>(&ip4), sizeof(ip4));
}
struct ClientStats {
size_t num_calls_started = 0;
size_t num_calls_finished = 0;
size_t num_calls_finished_with_client_failed_to_send = 0;
size_t num_calls_finished_known_received = 0;
std::map<grpc::string, size_t> drop_token_counts;
ClientStats& operator+=(const ClientStats& other) {
num_calls_started += other.num_calls_started;
num_calls_finished += other.num_calls_finished;
num_calls_finished_with_client_failed_to_send +=
other.num_calls_finished_with_client_failed_to_send;
num_calls_finished_known_received +=
other.num_calls_finished_known_received;
for (const auto& p : other.drop_token_counts) {
drop_token_counts[p.first] += p.second;
}
return *this;
}
};
class BalancerServiceImpl : public BalancerService {
public:
using Stream = ServerReaderWriter<LoadBalanceResponse, LoadBalanceRequest>;
using ResponseDelayPair = std::pair<LoadBalanceResponse, int>;
explicit BalancerServiceImpl(int client_load_reporting_interval_seconds)
: client_load_reporting_interval_seconds_(
client_load_reporting_interval_seconds),
shutdown_(false) {}
Status BalanceLoad(ServerContext* context, Stream* stream) override {
// Balancer shouldn't receive the call credentials metadata.
EXPECT_EQ(context->client_metadata().find(g_kCallCredsMdKey),
context->client_metadata().end());
gpr_log(GPR_INFO, "LB[%p]: BalanceLoad", this);
LoadBalanceRequest request;
std::vector<ResponseDelayPair> responses_and_delays;
if (!stream->Read(&request)) {
goto done;
}
IncreaseRequestCount();
gpr_log(GPR_INFO, "LB[%p]: received initial message '%s'", this,
request.DebugString().c_str());
// TODO(juanlishen): Initial response should always be the first response.
if (client_load_reporting_interval_seconds_ > 0) {
LoadBalanceResponse initial_response;
initial_response.mutable_initial_response()
->mutable_client_stats_report_interval()
->set_seconds(client_load_reporting_interval_seconds_);
stream->Write(initial_response);
}
{
std::unique_lock<std::mutex> lock(mu_);
responses_and_delays = responses_and_delays_;
}
for (const auto& response_and_delay : responses_and_delays) {
{
std::unique_lock<std::mutex> lock(mu_);
if (shutdown_) goto done;
}
SendResponse(stream, response_and_delay.first, response_and_delay.second);
}
{
std::unique_lock<std::mutex> lock(mu_);
if (shutdown_) goto done;
serverlist_cond_.wait(lock, [this] { return serverlist_ready_; });
}
if (client_load_reporting_interval_seconds_ > 0) {
request.Clear();
if (stream->Read(&request)) {
gpr_log(GPR_INFO, "LB[%p]: received client load report message '%s'",
this, request.DebugString().c_str());
GPR_ASSERT(request.has_client_stats());
// We need to acquire the lock here in order to prevent the notify_one
// below from firing before its corresponding wait is executed.
std::lock_guard<std::mutex> lock(mu_);
client_stats_.num_calls_started +=
request.client_stats().num_calls_started();
client_stats_.num_calls_finished +=
request.client_stats().num_calls_finished();
client_stats_.num_calls_finished_with_client_failed_to_send +=
request.client_stats()
.num_calls_finished_with_client_failed_to_send();
client_stats_.num_calls_finished_known_received +=
request.client_stats().num_calls_finished_known_received();
for (const auto& drop_token_count :
request.client_stats().calls_finished_with_drop()) {
client_stats_
.drop_token_counts[drop_token_count.load_balance_token()] +=
drop_token_count.num_calls();
}
load_report_ready_ = true;
load_report_cond_.notify_one();
}
}
done:
gpr_log(GPR_INFO, "LB[%p]: done", this);
return Status::OK;
}
void add_response(const LoadBalanceResponse& response, int send_after_ms) {
std::unique_lock<std::mutex> lock(mu_);
responses_and_delays_.push_back(std::make_pair(response, send_after_ms));
}
// Returns true on its first invocation, false otherwise.
bool Shutdown() {
NotifyDoneWithServerlists();
std::unique_lock<std::mutex> lock(mu_);
const bool prev = !shutdown_;
shutdown_ = true;
gpr_log(GPR_INFO, "LB[%p]: shut down", this);
return prev;
}
static LoadBalanceResponse BuildResponseForBackends(
const std::vector<int>& backend_ports,
const std::map<grpc::string, size_t>& drop_token_counts) {
LoadBalanceResponse response;
for (const auto& drop_token_count : drop_token_counts) {
for (size_t i = 0; i < drop_token_count.second; ++i) {
auto* server = response.mutable_server_list()->add_servers();
server->set_drop(true);
server->set_load_balance_token(drop_token_count.first);
}
}
for (const int& backend_port : backend_ports) {
auto* server = response.mutable_server_list()->add_servers();
server->set_ip_address(Ip4ToPackedString("127.0.0.1"));
server->set_port(backend_port);
static int token_count = 0;
char* token;
gpr_asprintf(&token, "token%03d", ++token_count);
server->set_load_balance_token(token);
gpr_free(token);
}
return response;
}
const ClientStats& WaitForLoadReport() {
std::unique_lock<std::mutex> lock(mu_);
load_report_cond_.wait(lock, [this] { return load_report_ready_; });
load_report_ready_ = false;
return client_stats_;
}
void NotifyDoneWithServerlists() {
std::lock_guard<std::mutex> lock(mu_);
serverlist_ready_ = true;
serverlist_cond_.notify_all();
}
private:
void SendResponse(Stream* stream, const LoadBalanceResponse& response,
int delay_ms) {
gpr_log(GPR_INFO, "LB[%p]: sleeping for %d ms...", this, delay_ms);
if (delay_ms > 0) {
gpr_sleep_until(grpc_timeout_milliseconds_to_deadline(delay_ms));
}
gpr_log(GPR_INFO, "LB[%p]: Woke up! Sending response '%s'", this,
response.DebugString().c_str());
IncreaseResponseCount();
stream->Write(response);
}
const int client_load_reporting_interval_seconds_;
std::vector<ResponseDelayPair> responses_and_delays_;
std::mutex mu_;
std::condition_variable load_report_cond_;
bool load_report_ready_ = false;
std::condition_variable serverlist_cond_;
bool serverlist_ready_ = false;
ClientStats client_stats_;
bool shutdown_;
};
class GrpclbEnd2endTest : public ::testing::Test {
protected:
GrpclbEnd2endTest(int num_backends, int num_balancers,
int client_load_reporting_interval_seconds)
: server_host_("localhost"),
num_backends_(num_backends),
num_balancers_(num_balancers),
client_load_reporting_interval_seconds_(
client_load_reporting_interval_seconds) {
// 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<grpc_core::FakeResolverResponseGenerator>();
// Start the backends.
for (size_t i = 0; i < num_backends_; ++i) {
backends_.emplace_back(new BackendServiceImpl());
backend_servers_.emplace_back(ServerThread<BackendService>(
"backend", server_host_, backends_.back().get()));
}
// Start the load balancers.
for (size_t i = 0; i < num_balancers_; ++i) {
balancers_.emplace_back(
new BalancerServiceImpl(client_load_reporting_interval_seconds_));
balancer_servers_.emplace_back(ServerThread<BalancerService>(
"balancer", server_host_, balancers_.back().get()));
}
ResetStub();
}
void TearDown() override {
for (size_t i = 0; i < backends_.size(); ++i) {
if (backends_[i]->Shutdown()) backend_servers_[i].Shutdown();
}
for (size_t i = 0; i < balancers_.size(); ++i) {
if (balancers_[i]->Shutdown()) balancer_servers_[i].Shutdown();
}
}
void ResetStub(int fallback_timeout = 0,
const grpc::string& expected_targets = "") {
ChannelArguments args;
args.SetGrpclbFallbackTimeout(fallback_timeout);
args.SetPointer(GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR,
response_generator_.get());
if (!expected_targets.empty()) {
args.SetString(GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS, expected_targets);
}
std::ostringstream uri;
uri << "fake:///" << kApplicationTargetName_;
// TODO(dgq): templatize tests to run everything using both secure and
// insecure channel credentials.
grpc_channel_credentials* channel_creds =
grpc_fake_transport_security_credentials_create();
grpc_call_credentials* call_creds = grpc_md_only_test_credentials_create(
g_kCallCredsMdKey, g_kCallCredsMdValue, false);
std::shared_ptr<ChannelCredentials> creds(
new SecureChannelCredentials(grpc_composite_channel_credentials_create(
channel_creds, call_creds, nullptr)));
call_creds->Unref();
channel_creds->Unref();
channel_ = CreateCustomChannel(uri.str(), creds, args);
stub_ = grpc::testing::EchoTestService::NewStub(channel_);
}
void ResetBackendCounters() {
for (const auto& backend : backends_) backend->ResetCounters();
}
ClientStats WaitForLoadReports() {
ClientStats client_stats;
for (const auto& balancer : balancers_) {
client_stats += balancer->WaitForLoadReport();
}
return client_stats;
}
bool SeenAllBackends() {
for (const auto& backend : backends_) {
if (backend->request_count() == 0) return false;
}
return true;
}
void SendRpcAndCount(int* num_total, int* num_ok, int* num_failure,
int* num_drops) {
const Status status = SendRpc();
if (status.ok()) {
++*num_ok;
} else {
if (status.error_message() == "Call dropped by load balancing policy") {
++*num_drops;
} else {
++*num_failure;
}
}
++*num_total;
}
std::tuple<int, int, int> WaitForAllBackends(
int num_requests_multiple_of = 1) {
int num_ok = 0;
int num_failure = 0;
int num_drops = 0;
int num_total = 0;
while (!SeenAllBackends()) {
SendRpcAndCount(&num_total, &num_ok, &num_failure, &num_drops);
}
while (num_total % num_requests_multiple_of != 0) {
SendRpcAndCount(&num_total, &num_ok, &num_failure, &num_drops);
}
ResetBackendCounters();
gpr_log(GPR_INFO,
"Performed %d warm up requests (a multiple of %d) against the "
"backends. %d succeeded, %d failed, %d dropped.",
num_total, num_requests_multiple_of, num_ok, num_failure,
num_drops);
return std::make_tuple(num_ok, num_failure, num_drops);
}
void WaitForBackend(size_t backend_idx) {
do {
(void)SendRpc();
} while (backends_[backend_idx]->request_count() == 0);
ResetBackendCounters();
}
struct AddressData {
int port;
bool is_balancer;
grpc::string balancer_name;
};
grpc_core::ServerAddressList CreateLbAddressesFromAddressDataList(
const std::vector<AddressData>& address_data) {
grpc_core::ServerAddressList addresses;
for (const auto& addr : address_data) {
char* lb_uri_str;
gpr_asprintf(&lb_uri_str, "ipv4:127.0.0.1:%d", addr.port);
grpc_uri* lb_uri = grpc_uri_parse(lb_uri_str, true);
GPR_ASSERT(lb_uri != nullptr);
grpc_resolved_address address;
GPR_ASSERT(grpc_parse_uri(lb_uri, &address));
std::vector<grpc_arg> args_to_add;
if (addr.is_balancer) {
args_to_add.emplace_back(grpc_channel_arg_integer_create(
const_cast<char*>(GRPC_ARG_ADDRESS_IS_BALANCER), 1));
args_to_add.emplace_back(grpc_channel_arg_string_create(
const_cast<char*>(GRPC_ARG_ADDRESS_BALANCER_NAME),
const_cast<char*>(addr.balancer_name.c_str())));
}
grpc_channel_args* args = grpc_channel_args_copy_and_add(
nullptr, args_to_add.data(), args_to_add.size());
addresses.emplace_back(address.addr, address.len, args);
grpc_uri_destroy(lb_uri);
gpr_free(lb_uri_str);
}
return addresses;
}
void SetNextResolutionAllBalancers(
const char* service_config_json = nullptr) {
std::vector<AddressData> addresses;
for (size_t i = 0; i < balancer_servers_.size(); ++i) {
addresses.emplace_back(AddressData{balancer_servers_[i].port_, true, ""});
}
SetNextResolution(addresses, service_config_json);
}
void SetNextResolution(const std::vector<AddressData>& address_data,
const char* service_config_json = nullptr) {
grpc_core::ExecCtx exec_ctx;
grpc_core::ServerAddressList addresses =
CreateLbAddressesFromAddressDataList(address_data);
std::vector<grpc_arg> args = {
CreateServerAddressListChannelArg(&addresses),
};
if (service_config_json != nullptr) {
args.push_back(grpc_channel_arg_string_create(
const_cast<char*>(GRPC_ARG_SERVICE_CONFIG),
const_cast<char*>(service_config_json)));
}
grpc_channel_args fake_result = {args.size(), args.data()};
response_generator_->SetResponse(&fake_result);
}
void SetNextReresolutionResponse(
const std::vector<AddressData>& address_data) {
grpc_core::ExecCtx exec_ctx;
grpc_core::ServerAddressList addresses =
CreateLbAddressesFromAddressDataList(address_data);
grpc_arg fake_addresses = CreateServerAddressListChannelArg(&addresses);
grpc_channel_args fake_result = {1, &fake_addresses};
response_generator_->SetReresolutionResponse(&fake_result);
}
const std::vector<int> GetBackendPorts(const size_t start_index = 0) const {
std::vector<int> backend_ports;
for (size_t i = start_index; i < backend_servers_.size(); ++i) {
backend_ports.push_back(backend_servers_[i].port_);
}
return backend_ports;
}
void ScheduleResponseForBalancer(size_t i,
const LoadBalanceResponse& response,
int delay_ms) {
balancers_.at(i)->add_response(response, delay_ms);
}
Status SendRpc(EchoResponse* response = nullptr, int timeout_ms = 1000,
bool wait_for_ready = false) {
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));
if (wait_for_ready) context.set_wait_for_ready(true);
Status status = stub_->Echo(&context, request, response);
if (local_response) delete response;
return status;
}
void CheckRpcSendOk(const size_t times = 1, const int timeout_ms = 1000,
bool wait_for_ready = false) {
for (size_t i = 0; i < times; ++i) {
EchoResponse response;
const Status status = SendRpc(&response, timeout_ms, wait_for_ready);
EXPECT_TRUE(status.ok()) << "code=" << status.error_code()
<< " message=" << status.error_message();
EXPECT_EQ(response.message(), kRequestMessage_);
}
}
void CheckRpcSendFailure() {
const Status status = SendRpc();
EXPECT_FALSE(status.ok());
}
template <typename T>
struct ServerThread {
explicit ServerThread(const grpc::string& type,
const grpc::string& server_host, T* service)
: type_(type), service_(service) {
std::mutex mu;
// We need to acquire the lock here in order to prevent the notify_one
// by ServerThread::Start from firing before the wait below is hit.
std::unique_lock<std::mutex> lock(mu);
port_ = grpc_pick_unused_port_or_die();
gpr_log(GPR_INFO, "starting %s server on port %d", type_.c_str(), port_);
std::condition_variable cond;
thread_.reset(new std::thread(
std::bind(&ServerThread::Start, this, server_host, &mu, &cond)));
cond.wait(lock);
gpr_log(GPR_INFO, "%s server startup complete", type_.c_str());
}
void Start(const grpc::string& server_host, std::mutex* mu,
std::condition_variable* cond) {
// We need to acquire the lock here in order to prevent the notify_one
// below from firing before its corresponding wait is executed.
std::lock_guard<std::mutex> lock(*mu);
std::ostringstream server_address;
server_address << server_host << ":" << port_;
ServerBuilder builder;
std::shared_ptr<ServerCredentials> creds(new SecureServerCredentials(
grpc_fake_transport_security_server_credentials_create()));
builder.AddListeningPort(server_address.str(), creds);
builder.RegisterService(service_);
server_ = builder.BuildAndStart();
cond->notify_one();
}
void Shutdown() {
gpr_log(GPR_INFO, "%s about to shutdown", type_.c_str());
server_->Shutdown(grpc_timeout_milliseconds_to_deadline(0));
thread_->join();
gpr_log(GPR_INFO, "%s shutdown completed", type_.c_str());
}
int port_;
grpc::string type_;
std::unique_ptr<Server> server_;
T* service_;
std::unique_ptr<std::thread> thread_;
};
const grpc::string server_host_;
const size_t num_backends_;
const size_t num_balancers_;
const int client_load_reporting_interval_seconds_;
std::shared_ptr<Channel> channel_;
std::unique_ptr<grpc::testing::EchoTestService::Stub> stub_;
std::vector<std::unique_ptr<BackendServiceImpl>> backends_;
std::vector<std::unique_ptr<BalancerServiceImpl>> balancers_;
std::vector<ServerThread<BackendService>> backend_servers_;
std::vector<ServerThread<BalancerService>> balancer_servers_;
grpc_core::RefCountedPtr<grpc_core::FakeResolverResponseGenerator>
response_generator_;
const grpc::string kRequestMessage_ = "Live long and prosper.";
const grpc::string kApplicationTargetName_ = "application_target_name";
};
class SingleBalancerTest : public GrpclbEnd2endTest {
public:
SingleBalancerTest() : GrpclbEnd2endTest(4, 1, 0) {}
};
TEST_F(SingleBalancerTest, Vanilla) {
SetNextResolutionAllBalancers();
const size_t kNumRpcsPerAddress = 100;
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
// Make sure that trying to connect works without a call.
channel_->GetState(true /* try_to_connect */);
// We need to wait for all backends to come online.
WaitForAllBackends();
// Send kNumRpcsPerAddress RPCs per server.
CheckRpcSendOk(kNumRpcsPerAddress * num_backends_);
// Each backend should have gotten 100 requests.
for (size_t i = 0; i < backends_.size(); ++i) {
EXPECT_EQ(kNumRpcsPerAddress,
backend_servers_[i].service_->request_count());
}
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
// Check LB policy name for the channel.
EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
}
TEST_F(SingleBalancerTest, SelectGrpclbWithMigrationServiceConfig) {
SetNextResolutionAllBalancers(
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"does_not_exist\":{} },\n"
" { \"grpclb\":{} }\n"
" ]\n"
"}");
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
CheckRpcSendOk(1, 1000 /* timeout_ms */, true /* wait_for_ready */);
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
// Check LB policy name for the channel.
EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
}
TEST_F(SingleBalancerTest,
SelectGrpclbWithMigrationServiceConfigAndNoAddresses) {
const int kFallbackTimeoutMs = 200 * grpc_test_slowdown_factor();
ResetStub(kFallbackTimeoutMs);
SetNextResolution({},
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"does_not_exist\":{} },\n"
" { \"grpclb\":{} }\n"
" ]\n"
"}");
// Try to connect.
EXPECT_EQ(GRPC_CHANNEL_IDLE, channel_->GetState(true));
// Should go into state TRANSIENT_FAILURE when we enter fallback mode.
const gpr_timespec deadline = grpc_timeout_seconds_to_deadline(1);
grpc_connectivity_state state;
while ((state = channel_->GetState(false)) !=
GRPC_CHANNEL_TRANSIENT_FAILURE) {
ASSERT_TRUE(channel_->WaitForStateChange(state, deadline));
}
// Check LB policy name for the channel.
EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
}
TEST_F(SingleBalancerTest,
SelectGrpclbWithMigrationServiceConfigAndNoBalancerAddresses) {
const int kFallbackTimeoutMs = 200 * grpc_test_slowdown_factor();
ResetStub(kFallbackTimeoutMs);
// Resolution includes fallback address but no balancers.
SetNextResolution({AddressData{backend_servers_[0].port_, false, ""}},
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"does_not_exist\":{} },\n"
" { \"grpclb\":{} }\n"
" ]\n"
"}");
CheckRpcSendOk(1, 1000 /* timeout_ms */, true /* wait_for_ready */);
// Check LB policy name for the channel.
EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
}
TEST_F(SingleBalancerTest, UsePickFirstChildPolicy) {
SetNextResolutionAllBalancers(
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"grpclb\":{\n"
" \"childPolicy\":[\n"
" { \"pick_first\":{} }\n"
" ]\n"
" } }\n"
" ]\n"
"}");
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
const size_t kNumRpcs = num_backends_ * 2;
CheckRpcSendOk(kNumRpcs, 1000 /* timeout_ms */, true /* wait_for_ready */);
balancers_[0]->NotifyDoneWithServerlists();
// Check that all requests went to the first backend. This verifies
// that we used pick_first instead of round_robin as the child policy.
EXPECT_EQ(backend_servers_[0].service_->request_count(), kNumRpcs);
for (size_t i = 1; i < backends_.size(); ++i) {
EXPECT_EQ(backend_servers_[i].service_->request_count(), 0UL);
}
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
// Check LB policy name for the channel.
EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
}
TEST_F(SingleBalancerTest, SwapChildPolicy) {
SetNextResolutionAllBalancers(
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"grpclb\":{\n"
" \"childPolicy\":[\n"
" { \"pick_first\":{} }\n"
" ]\n"
" } }\n"
" ]\n"
"}");
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
const size_t kNumRpcs = num_backends_ * 2;
CheckRpcSendOk(kNumRpcs, 1000 /* timeout_ms */, true /* wait_for_ready */);
// Check that all requests went to the first backend. This verifies
// that we used pick_first instead of round_robin as the child policy.
EXPECT_EQ(backend_servers_[0].service_->request_count(), kNumRpcs);
for (size_t i = 1; i < backends_.size(); ++i) {
EXPECT_EQ(backend_servers_[i].service_->request_count(), 0UL);
}
// Send new resolution that removes child policy from service config.
SetNextResolutionAllBalancers("{}");
WaitForAllBackends();
CheckRpcSendOk(kNumRpcs, 1000 /* timeout_ms */, true /* wait_for_ready */);
// Check that every backend saw the same number of requests. This verifies
// that we used round_robin.
for (size_t i = 0; i < backends_.size(); ++i) {
EXPECT_EQ(backend_servers_[i].service_->request_count(), 2UL);
}
// Done.
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
// Check LB policy name for the channel.
EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
}
TEST_F(SingleBalancerTest, UpdatesGoToMostRecentChildPolicy) {
const int kFallbackTimeoutMs = 200 * grpc_test_slowdown_factor();
ResetStub(kFallbackTimeoutMs);
int unreachable_balancer_port = grpc_pick_unused_port_or_die();
int unreachable_backend_port = grpc_pick_unused_port_or_die();
// Phase 1: Start with RR pointing to first backend.
gpr_log(GPR_INFO, "PHASE 1: Initial setup with RR with first backend");
SetNextResolution(
{
// Unreachable balancer.
{unreachable_balancer_port, true, ""},
// Fallback address: first backend.
{backend_servers_[0].port_, false, ""},
},
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"grpclb\":{\n"
" \"childPolicy\":[\n"
" { \"round_robin\":{} }\n"
" ]\n"
" } }\n"
" ]\n"
"}");
// RPCs should go to first backend.
WaitForBackend(0);
// Phase 2: Switch to PF pointing to unreachable backend.
gpr_log(GPR_INFO, "PHASE 2: Update to use PF with unreachable backend");
SetNextResolution(
{
// Unreachable balancer.
{unreachable_balancer_port, true, ""},
// Fallback address: unreachable backend.
{unreachable_backend_port, false, ""},
},
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"grpclb\":{\n"
" \"childPolicy\":[\n"
" { \"pick_first\":{} }\n"
" ]\n"
" } }\n"
" ]\n"
"}");
// RPCs should continue to go to the first backend, because the new
// PF child policy will never go into state READY.
WaitForBackend(0);
// Phase 3: Switch back to RR pointing to second and third backends.
// This ensures that we create a new policy rather than updating the
// pending PF policy.
gpr_log(GPR_INFO, "PHASE 3: Update to use RR again with two backends");
SetNextResolution(
{
// Unreachable balancer.
{unreachable_balancer_port, true, ""},
// Fallback address: second and third backends.
{backend_servers_[1].port_, false, ""},
{backend_servers_[2].port_, false, ""},
},
"{\n"
" \"loadBalancingConfig\":[\n"
" { \"grpclb\":{\n"
" \"childPolicy\":[\n"
" { \"round_robin\":{} }\n"
" ]\n"
" } }\n"
" ]\n"
"}");
// RPCs should go to the second and third backends.
WaitForBackend(1);
WaitForBackend(2);
}
TEST_F(SingleBalancerTest, SameBackendListedMultipleTimes) {
SetNextResolutionAllBalancers();
// Same backend listed twice.
std::vector<int> ports;
ports.push_back(backend_servers_[0].port_);
ports.push_back(backend_servers_[0].port_);
const size_t kNumRpcsPerAddress = 10;
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(ports, {}), 0);
// We need to wait for the backend to come online.
WaitForBackend(0);
// Send kNumRpcsPerAddress RPCs per server.
CheckRpcSendOk(kNumRpcsPerAddress * ports.size());
// Backend should have gotten 20 requests.
EXPECT_EQ(kNumRpcsPerAddress * 2,
backend_servers_[0].service_->request_count());
// And they should have come from a single client port, because of
// subchannel sharing.
EXPECT_EQ(1UL, backends_[0]->clients().size());
balancers_[0]->NotifyDoneWithServerlists();
}
TEST_F(SingleBalancerTest, SecureNaming) {
ResetStub(0, kApplicationTargetName_ + ";lb");
SetNextResolution({AddressData{balancer_servers_[0].port_, true, "lb"}});
const size_t kNumRpcsPerAddress = 100;
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
// Make sure that trying to connect works without a call.
channel_->GetState(true /* try_to_connect */);
// We need to wait for all backends to come online.
WaitForAllBackends();
// Send kNumRpcsPerAddress RPCs per server.
CheckRpcSendOk(kNumRpcsPerAddress * num_backends_);
// Each backend should have gotten 100 requests.
for (size_t i = 0; i < backends_.size(); ++i) {
EXPECT_EQ(kNumRpcsPerAddress,
backend_servers_[i].service_->request_count());
}
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
// Check LB policy name for the channel.
EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
}
TEST_F(SingleBalancerTest, SecureNamingDeathTest) {
::testing::FLAGS_gtest_death_test_style = "threadsafe";
// Make sure that we blow up (via abort() from the security connector) when
// the name from the balancer doesn't match expectations.
ASSERT_DEATH(
{
ResetStub(0, kApplicationTargetName_ + ";lb");
SetNextResolution(
{AddressData{balancer_servers_[0].port_, true, "woops"}});
channel_->WaitForConnected(grpc_timeout_seconds_to_deadline(1));
},
"");
}
TEST_F(SingleBalancerTest, InitiallyEmptyServerlist) {
SetNextResolutionAllBalancers();
const int kServerlistDelayMs = 500 * grpc_test_slowdown_factor();
const int kCallDeadlineMs = kServerlistDelayMs * 2;
// First response is an empty serverlist, sent right away.
ScheduleResponseForBalancer(0, LoadBalanceResponse(), 0);
// Send non-empty serverlist only after kServerlistDelayMs
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
kServerlistDelayMs);
const auto t0 = system_clock::now();
// Client will block: LB will initially send empty serverlist.
CheckRpcSendOk(1, kCallDeadlineMs, true /* wait_for_ready */);
const auto ellapsed_ms =
std::chrono::duration_cast<std::chrono::milliseconds>(
system_clock::now() - t0);
// but eventually, the LB sends a serverlist update that allows the call to
// proceed. The call delay must be larger than the delay in sending the
// populated serverlist but under the call's deadline (which is enforced by
// the call's deadline).
EXPECT_GT(ellapsed_ms.count(), kServerlistDelayMs);
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent two responses.
EXPECT_EQ(2U, balancer_servers_[0].service_->response_count());
}
TEST_F(SingleBalancerTest, AllServersUnreachableFailFast) {
SetNextResolutionAllBalancers();
const size_t kNumUnreachableServers = 5;
std::vector<int> ports;
for (size_t i = 0; i < kNumUnreachableServers; ++i) {
ports.push_back(grpc_pick_unused_port_or_die());
}
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(ports, {}), 0);
const Status status = SendRpc();
// The error shouldn't be DEADLINE_EXCEEDED.
EXPECT_EQ(StatusCode::UNAVAILABLE, status.error_code());
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
}
TEST_F(SingleBalancerTest, Fallback) {
SetNextResolutionAllBalancers();
const int kFallbackTimeoutMs = 200 * grpc_test_slowdown_factor();
const int kServerlistDelayMs = 500 * grpc_test_slowdown_factor();
const size_t kNumBackendInResolution = backends_.size() / 2;
ResetStub(kFallbackTimeoutMs);
std::vector<AddressData> addresses;
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
addresses.emplace_back(AddressData{backend_servers_[i].port_, false, ""});
}
SetNextResolution(addresses);
// Send non-empty serverlist only after kServerlistDelayMs.
ScheduleResponseForBalancer(
0,
BalancerServiceImpl::BuildResponseForBackends(
GetBackendPorts(kNumBackendInResolution /* start_index */), {}),
kServerlistDelayMs);
// Wait until all the fallback backends are reachable.
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
WaitForBackend(i);
}
// The first request.
gpr_log(GPR_INFO, "========= BEFORE FIRST BATCH ==========");
CheckRpcSendOk(kNumBackendInResolution);
gpr_log(GPR_INFO, "========= DONE WITH FIRST BATCH ==========");
// Fallback is used: each backend returned by the resolver should have
// gotten one request.
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
EXPECT_EQ(1U, backend_servers_[i].service_->request_count());
}
for (size_t i = kNumBackendInResolution; i < backends_.size(); ++i) {
EXPECT_EQ(0U, backend_servers_[i].service_->request_count());
}
// Wait until the serverlist reception has been processed and all backends
// in the serverlist are reachable.
for (size_t i = kNumBackendInResolution; i < backends_.size(); ++i) {
WaitForBackend(i);
}
// Send out the second request.
gpr_log(GPR_INFO, "========= BEFORE SECOND BATCH ==========");
CheckRpcSendOk(backends_.size() - kNumBackendInResolution);
gpr_log(GPR_INFO, "========= DONE WITH SECOND BATCH ==========");
// Serverlist is used: each backend returned by the balancer should
// have gotten one request.
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
EXPECT_EQ(0U, backend_servers_[i].service_->request_count());
}
for (size_t i = kNumBackendInResolution; i < backends_.size(); ++i) {
EXPECT_EQ(1U, backend_servers_[i].service_->request_count());
}
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
}
TEST_F(SingleBalancerTest, FallbackUpdate) {
SetNextResolutionAllBalancers();
const int kFallbackTimeoutMs = 200 * grpc_test_slowdown_factor();
const int kServerlistDelayMs = 500 * grpc_test_slowdown_factor();
const size_t kNumBackendInResolution = backends_.size() / 3;
const size_t kNumBackendInResolutionUpdate = backends_.size() / 3;
ResetStub(kFallbackTimeoutMs);
std::vector<AddressData> addresses;
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
addresses.emplace_back(AddressData{backend_servers_[i].port_, false, ""});
}
SetNextResolution(addresses);
// Send non-empty serverlist only after kServerlistDelayMs.
ScheduleResponseForBalancer(
0,
BalancerServiceImpl::BuildResponseForBackends(
GetBackendPorts(kNumBackendInResolution +
kNumBackendInResolutionUpdate /* start_index */),
{}),
kServerlistDelayMs);
// Wait until all the fallback backends are reachable.
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
WaitForBackend(i);
}
// The first request.
gpr_log(GPR_INFO, "========= BEFORE FIRST BATCH ==========");
CheckRpcSendOk(kNumBackendInResolution);
gpr_log(GPR_INFO, "========= DONE WITH FIRST BATCH ==========");
// Fallback is used: each backend returned by the resolver should have
// gotten one request.
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
EXPECT_EQ(1U, backend_servers_[i].service_->request_count());
}
for (size_t i = kNumBackendInResolution; i < backends_.size(); ++i) {
EXPECT_EQ(0U, backend_servers_[i].service_->request_count());
}
addresses.clear();
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
for (size_t i = kNumBackendInResolution;
i < kNumBackendInResolution + kNumBackendInResolutionUpdate; ++i) {
addresses.emplace_back(AddressData{backend_servers_[i].port_, false, ""});
}
SetNextResolution(addresses);
// Wait until the resolution update has been processed and all the new
// fallback backends are reachable.
for (size_t i = kNumBackendInResolution;
i < kNumBackendInResolution + kNumBackendInResolutionUpdate; ++i) {
WaitForBackend(i);
}
// Send out the second request.
gpr_log(GPR_INFO, "========= BEFORE SECOND BATCH ==========");
CheckRpcSendOk(kNumBackendInResolutionUpdate);
gpr_log(GPR_INFO, "========= DONE WITH SECOND BATCH ==========");
// The resolution update is used: each backend in the resolution update should
// have gotten one request.
for (size_t i = 0; i < kNumBackendInResolution; ++i) {
EXPECT_EQ(0U, backend_servers_[i].service_->request_count());
}
for (size_t i = kNumBackendInResolution;
i < kNumBackendInResolution + kNumBackendInResolutionUpdate; ++i) {
EXPECT_EQ(1U, backend_servers_[i].service_->request_count());
}
for (size_t i = kNumBackendInResolution + kNumBackendInResolutionUpdate;
i < backends_.size(); ++i) {
EXPECT_EQ(0U, backend_servers_[i].service_->request_count());
}
// Wait until the serverlist reception has been processed and all backends
// in the serverlist are reachable.
for (size_t i = kNumBackendInResolution + kNumBackendInResolutionUpdate;
i < backends_.size(); ++i) {
WaitForBackend(i);
}
// Send out the third request.
gpr_log(GPR_INFO, "========= BEFORE THIRD BATCH ==========");
CheckRpcSendOk(backends_.size() - kNumBackendInResolution -
kNumBackendInResolutionUpdate);
gpr_log(GPR_INFO, "========= DONE WITH THIRD BATCH ==========");
// Serverlist is used: each backend returned by the balancer should
// have gotten one request.
for (size_t i = 0;
i < kNumBackendInResolution + kNumBackendInResolutionUpdate; ++i) {
EXPECT_EQ(0U, backend_servers_[i].service_->request_count());
}
for (size_t i = kNumBackendInResolution + kNumBackendInResolutionUpdate;
i < backends_.size(); ++i) {
EXPECT_EQ(1U, backend_servers_[i].service_->request_count());
}
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
}
TEST_F(SingleBalancerTest, BackendsRestart) {
SetNextResolutionAllBalancers();
const size_t kNumRpcsPerAddress = 100;
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
// Make sure that trying to connect works without a call.
channel_->GetState(true /* try_to_connect */);
// Send kNumRpcsPerAddress RPCs per server.
CheckRpcSendOk(kNumRpcsPerAddress * num_backends_);
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
for (size_t i = 0; i < backends_.size(); ++i) {
if (backends_[i]->Shutdown()) backend_servers_[i].Shutdown();
}
CheckRpcSendFailure();
for (size_t i = 0; i < num_backends_; ++i) {
backends_.emplace_back(new BackendServiceImpl());
backend_servers_.emplace_back(ServerThread<BackendService>(
"backend", server_host_, backends_.back().get()));
}
// The following RPC will fail due to the backend ports having changed. It
// will nonetheless exercise the grpclb-roundrobin handling of the RR policy
// having gone into shutdown.
// TODO(dgq): implement the "backend restart" component as well. We need extra
// machinery to either update the LB responses "on the fly" or instruct
// backends which ports to restart on.
CheckRpcSendFailure();
}
class UpdatesTest : public GrpclbEnd2endTest {
public:
UpdatesTest() : GrpclbEnd2endTest(4, 3, 0) {}
};
TEST_F(UpdatesTest, UpdateBalancers) {
SetNextResolutionAllBalancers();
const std::vector<int> first_backend{GetBackendPorts()[0]};
const std::vector<int> second_backend{GetBackendPorts()[1]};
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(first_backend, {}), 0);
ScheduleResponseForBalancer(
1, BalancerServiceImpl::BuildResponseForBackends(second_backend, {}), 0);
// Wait until the first backend is ready.
WaitForBackend(0);
// Send 10 requests.
gpr_log(GPR_INFO, "========= BEFORE FIRST BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH FIRST BATCH ==========");
// All 10 requests should have gone to the first backend.
EXPECT_EQ(10U, backend_servers_[0].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
balancers_[1]->NotifyDoneWithServerlists();
balancers_[2]->NotifyDoneWithServerlists();
// Balancer 0 got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
std::vector<AddressData> addresses;
addresses.emplace_back(AddressData{balancer_servers_[1].port_, true, ""});
gpr_log(GPR_INFO, "========= ABOUT TO UPDATE 1 ==========");
SetNextResolution(addresses);
gpr_log(GPR_INFO, "========= UPDATE 1 DONE ==========");
// Wait until update has been processed, as signaled by the second backend
// receiving a request.
EXPECT_EQ(0U, backend_servers_[1].service_->request_count());
WaitForBackend(1);
backend_servers_[1].service_->ResetCounters();
gpr_log(GPR_INFO, "========= BEFORE SECOND BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH SECOND BATCH ==========");
// All 10 requests should have gone to the second backend.
EXPECT_EQ(10U, backend_servers_[1].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
balancers_[1]->NotifyDoneWithServerlists();
balancers_[2]->NotifyDoneWithServerlists();
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
EXPECT_EQ(1U, balancer_servers_[1].service_->request_count());
EXPECT_EQ(1U, balancer_servers_[1].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
}
// Send an update with the same set of LBs as the one in SetUp() in order to
// verify that the LB channel inside grpclb keeps the initial connection (which
// by definition is also present in the update).
TEST_F(UpdatesTest, UpdateBalancersRepeated) {
SetNextResolutionAllBalancers();
const std::vector<int> first_backend{GetBackendPorts()[0]};
const std::vector<int> second_backend{GetBackendPorts()[0]};
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(first_backend, {}), 0);
ScheduleResponseForBalancer(
1, BalancerServiceImpl::BuildResponseForBackends(second_backend, {}), 0);
// Wait until the first backend is ready.
WaitForBackend(0);
// Send 10 requests.
gpr_log(GPR_INFO, "========= BEFORE FIRST BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH FIRST BATCH ==========");
// All 10 requests should have gone to the first backend.
EXPECT_EQ(10U, backend_servers_[0].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
// Balancer 0 got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
std::vector<AddressData> addresses;
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
addresses.emplace_back(AddressData{balancer_servers_[1].port_, true, ""});
addresses.emplace_back(AddressData{balancer_servers_[2].port_, true, ""});
gpr_log(GPR_INFO, "========= ABOUT TO UPDATE 1 ==========");
SetNextResolution(addresses);
gpr_log(GPR_INFO, "========= UPDATE 1 DONE ==========");
EXPECT_EQ(0U, backend_servers_[1].service_->request_count());
gpr_timespec deadline = gpr_time_add(
gpr_now(GPR_CLOCK_REALTIME), gpr_time_from_millis(10000, GPR_TIMESPAN));
// Send 10 seconds worth of RPCs
do {
CheckRpcSendOk();
} while (gpr_time_cmp(gpr_now(GPR_CLOCK_REALTIME), deadline) < 0);
// grpclb continued using the original LB call to the first balancer, which
// doesn't assign the second backend.
EXPECT_EQ(0U, backend_servers_[1].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
addresses.clear();
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
addresses.emplace_back(AddressData{balancer_servers_[1].port_, true, ""});
gpr_log(GPR_INFO, "========= ABOUT TO UPDATE 2 ==========");
SetNextResolution(addresses);
gpr_log(GPR_INFO, "========= UPDATE 2 DONE ==========");
EXPECT_EQ(0U, backend_servers_[1].service_->request_count());
deadline = gpr_time_add(gpr_now(GPR_CLOCK_REALTIME),
gpr_time_from_millis(10000, GPR_TIMESPAN));
// Send 10 seconds worth of RPCs
do {
CheckRpcSendOk();
} while (gpr_time_cmp(gpr_now(GPR_CLOCK_REALTIME), deadline) < 0);
// grpclb continued using the original LB call to the first balancer, which
// doesn't assign the second backend.
EXPECT_EQ(0U, backend_servers_[1].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
}
TEST_F(UpdatesTest, UpdateBalancersDeadUpdate) {
std::vector<AddressData> addresses;
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
SetNextResolution(addresses);
const std::vector<int> first_backend{GetBackendPorts()[0]};
const std::vector<int> second_backend{GetBackendPorts()[1]};
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(first_backend, {}), 0);
ScheduleResponseForBalancer(
1, BalancerServiceImpl::BuildResponseForBackends(second_backend, {}), 0);
// Start servers and send 10 RPCs per server.
gpr_log(GPR_INFO, "========= BEFORE FIRST BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH FIRST BATCH ==========");
// All 10 requests should have gone to the first backend.
EXPECT_EQ(10U, backend_servers_[0].service_->request_count());
// Kill balancer 0
gpr_log(GPR_INFO, "********** ABOUT TO KILL BALANCER 0 *************");
balancers_[0]->NotifyDoneWithServerlists();
if (balancers_[0]->Shutdown()) balancer_servers_[0].Shutdown();
gpr_log(GPR_INFO, "********** KILLED BALANCER 0 *************");
// This is serviced by the existing RR policy
gpr_log(GPR_INFO, "========= BEFORE SECOND BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH SECOND BATCH ==========");
// All 10 requests should again have gone to the first backend.
EXPECT_EQ(20U, backend_servers_[0].service_->request_count());
EXPECT_EQ(0U, backend_servers_[1].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
balancers_[1]->NotifyDoneWithServerlists();
balancers_[2]->NotifyDoneWithServerlists();
// Balancer 0 got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
addresses.clear();
addresses.emplace_back(AddressData{balancer_servers_[1].port_, true, ""});
gpr_log(GPR_INFO, "========= ABOUT TO UPDATE 1 ==========");
SetNextResolution(addresses);
gpr_log(GPR_INFO, "========= UPDATE 1 DONE ==========");
// Wait until update has been processed, as signaled by the second backend
// receiving a request. In the meantime, the client continues to be serviced
// (by the first backend) without interruption.
EXPECT_EQ(0U, backend_servers_[1].service_->request_count());
WaitForBackend(1);
// This is serviced by the updated RR policy
backend_servers_[1].service_->ResetCounters();
gpr_log(GPR_INFO, "========= BEFORE THIRD BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH THIRD BATCH ==========");
// All 10 requests should have gone to the second backend.
EXPECT_EQ(10U, backend_servers_[1].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
balancers_[1]->NotifyDoneWithServerlists();
balancers_[2]->NotifyDoneWithServerlists();
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
// The second balancer, published as part of the first update, may end up
// getting two requests (that is, 1 <= #req <= 2) if the LB call retry timer
// firing races with the arrival of the update containing the second
// balancer.
EXPECT_GE(balancer_servers_[1].service_->request_count(), 1U);
EXPECT_GE(balancer_servers_[1].service_->response_count(), 1U);
EXPECT_LE(balancer_servers_[1].service_->request_count(), 2U);
EXPECT_LE(balancer_servers_[1].service_->response_count(), 2U);
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
}
TEST_F(UpdatesTest, ReresolveDeadBackend) {
ResetStub(500);
// The first resolution contains the addresses of a balancer that never
// responds, and a fallback backend.
std::vector<AddressData> addresses;
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
addresses.emplace_back(AddressData{backend_servers_[0].port_, false, ""});
SetNextResolution(addresses);
// The re-resolution result will contain the addresses of the same balancer
// and a new fallback backend.
addresses.clear();
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
addresses.emplace_back(AddressData{backend_servers_[1].port_, false, ""});
SetNextReresolutionResponse(addresses);
// Start servers and send 10 RPCs per server.
gpr_log(GPR_INFO, "========= BEFORE FIRST BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH FIRST BATCH ==========");
// All 10 requests should have gone to the fallback backend.
EXPECT_EQ(10U, backend_servers_[0].service_->request_count());
// Kill backend 0.
gpr_log(GPR_INFO, "********** ABOUT TO KILL BACKEND 0 *************");
if (backends_[0]->Shutdown()) backend_servers_[0].Shutdown();
gpr_log(GPR_INFO, "********** KILLED BACKEND 0 *************");
// Wait until re-resolution has finished, as signaled by the second backend
// receiving a request.
WaitForBackend(1);
gpr_log(GPR_INFO, "========= BEFORE SECOND BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH SECOND BATCH ==========");
// All 10 requests should have gone to the second backend.
EXPECT_EQ(10U, backend_servers_[1].service_->request_count());
balancers_[0]->NotifyDoneWithServerlists();
balancers_[1]->NotifyDoneWithServerlists();
balancers_[2]->NotifyDoneWithServerlists();
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[0].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
}
// TODO(juanlishen): Should be removed when the first response is always the
// initial response. Currently, if client load reporting is not enabled, the
// balancer doesn't send initial response. When the backend shuts down, an
// unexpected re-resolution will happen. This test configuration is a workaround
// for test ReresolveDeadBalancer.
class UpdatesWithClientLoadReportingTest : public GrpclbEnd2endTest {
public:
UpdatesWithClientLoadReportingTest() : GrpclbEnd2endTest(4, 3, 2) {}
};
TEST_F(UpdatesWithClientLoadReportingTest, ReresolveDeadBalancer) {
std::vector<AddressData> addresses;
addresses.emplace_back(AddressData{balancer_servers_[0].port_, true, ""});
SetNextResolution(addresses);
addresses.clear();
addresses.emplace_back(AddressData{balancer_servers_[1].port_, true, ""});
SetNextReresolutionResponse(addresses);
const std::vector<int> first_backend{GetBackendPorts()[0]};
const std::vector<int> second_backend{GetBackendPorts()[1]};
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(first_backend, {}), 0);
ScheduleResponseForBalancer(
1, BalancerServiceImpl::BuildResponseForBackends(second_backend, {}), 0);
// Start servers and send 10 RPCs per server.
gpr_log(GPR_INFO, "========= BEFORE FIRST BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH FIRST BATCH ==========");
// All 10 requests should have gone to the first backend.
EXPECT_EQ(10U, backend_servers_[0].service_->request_count());
// Kill backend 0.
gpr_log(GPR_INFO, "********** ABOUT TO KILL BACKEND 0 *************");
if (backends_[0]->Shutdown()) backend_servers_[0].Shutdown();
gpr_log(GPR_INFO, "********** KILLED BACKEND 0 *************");
CheckRpcSendFailure();
// Balancer 0 got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[1].service_->response_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
// Kill balancer 0.
gpr_log(GPR_INFO, "********** ABOUT TO KILL BALANCER 0 *************");
if (balancers_[0]->Shutdown()) balancer_servers_[0].Shutdown();
gpr_log(GPR_INFO, "********** KILLED BALANCER 0 *************");
// Wait until re-resolution has finished, as signaled by the second backend
// receiving a request.
WaitForBackend(1);
// This is serviced by the new serverlist.
gpr_log(GPR_INFO, "========= BEFORE SECOND BATCH ==========");
CheckRpcSendOk(10);
gpr_log(GPR_INFO, "========= DONE WITH SECOND BATCH ==========");
// All 10 requests should have gone to the second backend.
EXPECT_EQ(10U, backend_servers_[1].service_->request_count());
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
// After balancer 0 is killed, we restart an LB call immediately (because we
// disconnect to a previously connected balancer). Although we will cancel
// this call when the re-resolution update is done and another LB call restart
// is needed, this old call may still succeed reaching the LB server if
// re-resolution is slow. So balancer 1 may have received 2 requests and sent
// 2 responses.
EXPECT_GE(balancer_servers_[1].service_->request_count(), 1U);
EXPECT_GE(balancer_servers_[1].service_->response_count(), 1U);
EXPECT_LE(balancer_servers_[1].service_->request_count(), 2U);
EXPECT_LE(balancer_servers_[1].service_->response_count(), 2U);
EXPECT_EQ(0U, balancer_servers_[2].service_->request_count());
EXPECT_EQ(0U, balancer_servers_[2].service_->response_count());
}
TEST_F(SingleBalancerTest, Drop) {
SetNextResolutionAllBalancers();
const size_t kNumRpcsPerAddress = 100;
const int num_of_drop_by_rate_limiting_addresses = 1;
const int num_of_drop_by_load_balancing_addresses = 2;
const int num_of_drop_addresses = num_of_drop_by_rate_limiting_addresses +
num_of_drop_by_load_balancing_addresses;
const int num_total_addresses = num_backends_ + num_of_drop_addresses;
ScheduleResponseForBalancer(
0,
BalancerServiceImpl::BuildResponseForBackends(
GetBackendPorts(),
{{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
{"load_balancing", num_of_drop_by_load_balancing_addresses}}),
0);
// Wait until all backends are ready.
WaitForAllBackends();
// Send kNumRpcsPerAddress RPCs for each server and drop address.
size_t num_drops = 0;
for (size_t i = 0; i < kNumRpcsPerAddress * num_total_addresses; ++i) {
EchoResponse response;
const Status status = SendRpc(&response);
if (!status.ok() &&
status.error_message() == "Call dropped by load balancing policy") {
++num_drops;
} else {
EXPECT_TRUE(status.ok()) << "code=" << status.error_code()
<< " message=" << status.error_message();
EXPECT_EQ(response.message(), kRequestMessage_);
}
}
EXPECT_EQ(kNumRpcsPerAddress * num_of_drop_addresses, num_drops);
// Each backend should have gotten 100 requests.
for (size_t i = 0; i < backends_.size(); ++i) {
EXPECT_EQ(kNumRpcsPerAddress,
backend_servers_[i].service_->request_count());
}
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
}
TEST_F(SingleBalancerTest, DropAllFirst) {
SetNextResolutionAllBalancers();
// All registered addresses are marked as "drop".
const int num_of_drop_by_rate_limiting_addresses = 1;
const int num_of_drop_by_load_balancing_addresses = 1;
ScheduleResponseForBalancer(
0,
BalancerServiceImpl::BuildResponseForBackends(
{}, {{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
{"load_balancing", num_of_drop_by_load_balancing_addresses}}),
0);
const Status status = SendRpc(nullptr, 1000, true);
EXPECT_FALSE(status.ok());
EXPECT_EQ(status.error_message(), "Call dropped by load balancing policy");
}
TEST_F(SingleBalancerTest, DropAll) {
SetNextResolutionAllBalancers();
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
const int num_of_drop_by_rate_limiting_addresses = 1;
const int num_of_drop_by_load_balancing_addresses = 1;
ScheduleResponseForBalancer(
0,
BalancerServiceImpl::BuildResponseForBackends(
{}, {{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
{"load_balancing", num_of_drop_by_load_balancing_addresses}}),
1000);
// First call succeeds.
CheckRpcSendOk();
// But eventually, the update with only dropped servers is processed and calls
// fail.
Status status;
do {
status = SendRpc(nullptr, 1000, true);
} while (status.ok());
EXPECT_FALSE(status.ok());
EXPECT_EQ(status.error_message(), "Call dropped by load balancing policy");
}
class SingleBalancerWithClientLoadReportingTest : public GrpclbEnd2endTest {
public:
SingleBalancerWithClientLoadReportingTest() : GrpclbEnd2endTest(4, 1, 3) {}
};
// TODO(roth): Add test that when switching balancers, we don't include
// any calls that were sent prior to connecting to the new balancer.
TEST_F(SingleBalancerWithClientLoadReportingTest, Vanilla) {
SetNextResolutionAllBalancers();
const size_t kNumRpcsPerAddress = 100;
ScheduleResponseForBalancer(
0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
0);
// Wait until all backends are ready.
int num_ok = 0;
int num_failure = 0;
int num_drops = 0;
std::tie(num_ok, num_failure, num_drops) = WaitForAllBackends();
// Send kNumRpcsPerAddress RPCs per server.
CheckRpcSendOk(kNumRpcsPerAddress * num_backends_);
// Each backend should have gotten 100 requests.
for (size_t i = 0; i < backends_.size(); ++i) {
EXPECT_EQ(kNumRpcsPerAddress,
backend_servers_[i].service_->request_count());
}
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
const ClientStats client_stats = WaitForLoadReports();
EXPECT_EQ(kNumRpcsPerAddress * num_backends_ + num_ok,
client_stats.num_calls_started);
EXPECT_EQ(kNumRpcsPerAddress * num_backends_ + num_ok,
client_stats.num_calls_finished);
EXPECT_EQ(0U, client_stats.num_calls_finished_with_client_failed_to_send);
EXPECT_EQ(kNumRpcsPerAddress * num_backends_ + (num_ok + num_drops),
client_stats.num_calls_finished_known_received);
EXPECT_THAT(client_stats.drop_token_counts, ::testing::ElementsAre());
}
TEST_F(SingleBalancerWithClientLoadReportingTest, Drop) {
SetNextResolutionAllBalancers();
const size_t kNumRpcsPerAddress = 3;
const int num_of_drop_by_rate_limiting_addresses = 2;
const int num_of_drop_by_load_balancing_addresses = 1;
const int num_of_drop_addresses = num_of_drop_by_rate_limiting_addresses +
num_of_drop_by_load_balancing_addresses;
const int num_total_addresses = num_backends_ + num_of_drop_addresses;
ScheduleResponseForBalancer(
0,
BalancerServiceImpl::BuildResponseForBackends(
GetBackendPorts(),
{{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
{"load_balancing", num_of_drop_by_load_balancing_addresses}}),
0);
// Wait until all backends are ready.
int num_warmup_ok = 0;
int num_warmup_failure = 0;
int num_warmup_drops = 0;
std::tie(num_warmup_ok, num_warmup_failure, num_warmup_drops) =
WaitForAllBackends(num_total_addresses /* num_requests_multiple_of */);
const int num_total_warmup_requests =
num_warmup_ok + num_warmup_failure + num_warmup_drops;
size_t num_drops = 0;
for (size_t i = 0; i < kNumRpcsPerAddress * num_total_addresses; ++i) {
EchoResponse response;
const Status status = SendRpc(&response);
if (!status.ok() &&
status.error_message() == "Call dropped by load balancing policy") {
++num_drops;
} else {
EXPECT_TRUE(status.ok()) << "code=" << status.error_code()
<< " message=" << status.error_message();
EXPECT_EQ(response.message(), kRequestMessage_);
}
}
EXPECT_EQ(kNumRpcsPerAddress * num_of_drop_addresses, num_drops);
// Each backend should have gotten 100 requests.
for (size_t i = 0; i < backends_.size(); ++i) {
EXPECT_EQ(kNumRpcsPerAddress,
backend_servers_[i].service_->request_count());
}
balancers_[0]->NotifyDoneWithServerlists();
// The balancer got a single request.
EXPECT_EQ(1U, balancer_servers_[0].service_->request_count());
// and sent a single response.
EXPECT_EQ(1U, balancer_servers_[0].service_->response_count());
const ClientStats client_stats = WaitForLoadReports();
EXPECT_EQ(
kNumRpcsPerAddress * num_total_addresses + num_total_warmup_requests,
client_stats.num_calls_started);
EXPECT_EQ(
kNumRpcsPerAddress * num_total_addresses + num_total_warmup_requests,
client_stats.num_calls_finished);
EXPECT_EQ(0U, client_stats.num_calls_finished_with_client_failed_to_send);
EXPECT_EQ(kNumRpcsPerAddress * num_backends_ + num_warmup_ok,
client_stats.num_calls_finished_known_received);
// The number of warmup request is a multiple of the number of addresses.
// Therefore, all addresses in the scheduled balancer response are hit the
// same number of times.
const int num_times_drop_addresses_hit =
num_warmup_drops / num_of_drop_addresses;
EXPECT_THAT(
client_stats.drop_token_counts,
::testing::ElementsAre(
::testing::Pair("load_balancing",
(kNumRpcsPerAddress + num_times_drop_addresses_hit)),
::testing::Pair(
"rate_limiting",
(kNumRpcsPerAddress + num_times_drop_addresses_hit) * 2)));
}
} // namespace
} // namespace testing
} // namespace grpc
int main(int argc, char** argv) {
grpc_init();
grpc::testing::TestEnvironment env(argc, argv);
::testing::InitGoogleTest(&argc, argv);
const auto result = RUN_ALL_TESTS();
grpc_shutdown();
return result;
}