diff options
Diffstat (limited to 'src/cpp/server/health/default_health_check_service.cc')
| -rw-r--r-- | src/cpp/server/health/default_health_check_service.cc | 484 |
1 files changed, 423 insertions, 61 deletions
diff --git a/src/cpp/server/health/default_health_check_service.cc b/src/cpp/server/health/default_health_check_service.cc index bfda67d086..670da63a4a 100644 --- a/src/cpp/server/health/default_health_check_service.cc +++ b/src/cpp/server/health/default_health_check_service.cc @@ -30,29 +30,162 @@ #include "src/cpp/server/health/health.pb.h" namespace grpc { + +// +// DefaultHealthCheckService +// + +DefaultHealthCheckService::DefaultHealthCheckService() { + services_map_[""].SetServingStatus(SERVING); +} + +void DefaultHealthCheckService::SetServingStatus( + const grpc::string& service_name, bool serving) { + std::unique_lock<std::mutex> lock(mu_); + services_map_[service_name].SetServingStatus(serving ? SERVING : NOT_SERVING); +} + +void DefaultHealthCheckService::SetServingStatus(bool serving) { + const ServingStatus status = serving ? SERVING : NOT_SERVING; + std::unique_lock<std::mutex> lock(mu_); + for (auto& p : services_map_) { + ServiceData& service_data = p.second; + service_data.SetServingStatus(status); + } +} + +DefaultHealthCheckService::ServingStatus +DefaultHealthCheckService::GetServingStatus( + const grpc::string& service_name) const { + std::lock_guard<std::mutex> lock(mu_); + auto it = services_map_.find(service_name); + if (it == services_map_.end()) { + return NOT_FOUND; + } + const ServiceData& service_data = it->second; + return service_data.GetServingStatus(); +} + +void DefaultHealthCheckService::RegisterCallHandler( + const grpc::string& service_name, + std::shared_ptr<HealthCheckServiceImpl::CallHandler> handler) { + std::unique_lock<std::mutex> lock(mu_); + ServiceData& service_data = services_map_[service_name]; + service_data.AddCallHandler(handler /* copies ref */); + handler->SendHealth(std::move(handler), service_data.GetServingStatus()); +} + +void DefaultHealthCheckService::UnregisterCallHandler( + const grpc::string& service_name, + std::shared_ptr<HealthCheckServiceImpl::CallHandler> handler) { + std::unique_lock<std::mutex> lock(mu_); + auto it = services_map_.find(service_name); + if (it == services_map_.end()) return; + ServiceData& service_data = it->second; + service_data.RemoveCallHandler(std::move(handler)); + if (service_data.Unused()) { + services_map_.erase(it); + } +} + +DefaultHealthCheckService::HealthCheckServiceImpl* +DefaultHealthCheckService::GetHealthCheckService( + std::unique_ptr<ServerCompletionQueue> cq) { + GPR_ASSERT(impl_ == nullptr); + impl_.reset(new HealthCheckServiceImpl(this, std::move(cq))); + return impl_.get(); +} + +// +// DefaultHealthCheckService::ServiceData +// + +void DefaultHealthCheckService::ServiceData::SetServingStatus( + ServingStatus status) { + status_ = status; + for (auto& call_handler : call_handlers_) { + call_handler->SendHealth(call_handler /* copies ref */, status); + } +} + +void DefaultHealthCheckService::ServiceData::AddCallHandler( + std::shared_ptr<HealthCheckServiceImpl::CallHandler> handler) { + call_handlers_.insert(std::move(handler)); +} + +void DefaultHealthCheckService::ServiceData::RemoveCallHandler( + std::shared_ptr<HealthCheckServiceImpl::CallHandler> handler) { + call_handlers_.erase(std::move(handler)); +} + +// +// DefaultHealthCheckService::HealthCheckServiceImpl +// + namespace { const char kHealthCheckMethodName[] = "/grpc.health.v1.Health/Check"; +const char kHealthWatchMethodName[] = "/grpc.health.v1.Health/Watch"; } // namespace DefaultHealthCheckService::HealthCheckServiceImpl::HealthCheckServiceImpl( - DefaultHealthCheckService* service) - : service_(service), method_(nullptr) { - internal::MethodHandler* handler = - new internal::RpcMethodHandler<HealthCheckServiceImpl, ByteBuffer, - ByteBuffer>( - std::mem_fn(&HealthCheckServiceImpl::Check), this); - method_ = new internal::RpcServiceMethod( - kHealthCheckMethodName, internal::RpcMethod::NORMAL_RPC, handler); - AddMethod(method_); -} - -Status DefaultHealthCheckService::HealthCheckServiceImpl::Check( - ServerContext* context, const ByteBuffer* request, ByteBuffer* response) { - // Decode request. - std::vector<Slice> slices; - if (!request->Dump(&slices).ok()) { - return Status(StatusCode::INVALID_ARGUMENT, ""); + DefaultHealthCheckService* database, + std::unique_ptr<ServerCompletionQueue> cq) + : database_(database), cq_(std::move(cq)) { + // Add Check() method. + check_method_ = new internal::RpcServiceMethod( + kHealthCheckMethodName, internal::RpcMethod::NORMAL_RPC, nullptr); + AddMethod(check_method_); + // Add Watch() method. + watch_method_ = new internal::RpcServiceMethod( + kHealthWatchMethodName, internal::RpcMethod::SERVER_STREAMING, nullptr); + AddMethod(watch_method_); + // Create serving thread. + thread_ = std::unique_ptr<::grpc_core::Thread>( + new ::grpc_core::Thread("grpc_health_check_service", Serve, this)); +} + +DefaultHealthCheckService::HealthCheckServiceImpl::~HealthCheckServiceImpl() { + // We will reach here after the server starts shutting down. + shutdown_ = true; + { + std::unique_lock<std::mutex> lock(cq_shutdown_mu_); + cq_->Shutdown(); + } + thread_->Join(); +} + +void DefaultHealthCheckService::HealthCheckServiceImpl::StartServingThread() { + thread_->Start(); +} + +void DefaultHealthCheckService::HealthCheckServiceImpl::Serve(void* arg) { + HealthCheckServiceImpl* service = + reinterpret_cast<HealthCheckServiceImpl*>(arg); + // TODO(juanlishen): This is a workaround to wait for the cq to be ready. + // Need to figure out why cq is not ready after service starts. + gpr_sleep_until(gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC), + gpr_time_from_seconds(1, GPR_TIMESPAN))); + CheckCallHandler::CreateAndStart(service->cq_.get(), service->database_, + service); + WatchCallHandler::CreateAndStart(service->cq_.get(), service->database_, + service); + void* tag; + bool ok; + while (true) { + if (!service->cq_->Next(&tag, &ok)) { + // The completion queue is shutting down. + GPR_ASSERT(service->shutdown_); + break; + } + auto* next_step = static_cast<CallableTag*>(tag); + next_step->Run(ok); } +} + +bool DefaultHealthCheckService::HealthCheckServiceImpl::DecodeRequest( + const ByteBuffer& request, grpc::string* service_name) { + std::vector<Slice> slices; + if (!request.Dump(&slices).ok()) return false; uint8_t* request_bytes = nullptr; bool request_bytes_owned = false; size_t request_size = 0; @@ -64,14 +197,13 @@ Status DefaultHealthCheckService::HealthCheckServiceImpl::Check( request_size = slices[0].size(); } else { request_bytes_owned = true; - request_bytes = static_cast<uint8_t*>(gpr_malloc(request->Length())); + request_bytes = static_cast<uint8_t*>(gpr_malloc(request.Length())); uint8_t* copy_to = request_bytes; for (size_t i = 0; i < slices.size(); i++) { memcpy(copy_to, slices[i].begin(), slices[i].size()); copy_to += slices[i].size(); } } - if (request_bytes != nullptr) { pb_istream_t istream = pb_istream_from_buffer(request_bytes, request_size); bool decode_status = pb_decode( @@ -79,26 +211,22 @@ Status DefaultHealthCheckService::HealthCheckServiceImpl::Check( if (request_bytes_owned) { gpr_free(request_bytes); } - if (!decode_status) { - return Status(StatusCode::INVALID_ARGUMENT, ""); - } - } - - // Check status from the associated default health checking service. - DefaultHealthCheckService::ServingStatus serving_status = - service_->GetServingStatus( - request_struct.has_service ? request_struct.service : ""); - if (serving_status == DefaultHealthCheckService::NOT_FOUND) { - return Status(StatusCode::NOT_FOUND, ""); + if (!decode_status) return false; } + *service_name = request_struct.has_service ? request_struct.service : ""; + return true; +} - // Encode response +bool DefaultHealthCheckService::HealthCheckServiceImpl::EncodeResponse( + ServingStatus status, ByteBuffer* response) { grpc_health_v1_HealthCheckResponse response_struct; response_struct.has_status = true; response_struct.status = - serving_status == DefaultHealthCheckService::SERVING - ? grpc_health_v1_HealthCheckResponse_ServingStatus_SERVING - : grpc_health_v1_HealthCheckResponse_ServingStatus_NOT_SERVING; + status == NOT_FOUND + ? grpc_health_v1_HealthCheckResponse_ServingStatus_SERVICE_UNKNOWN + : status == SERVING + ? grpc_health_v1_HealthCheckResponse_ServingStatus_SERVING + : grpc_health_v1_HealthCheckResponse_ServingStatus_NOT_SERVING; pb_ostream_t ostream; memset(&ostream, 0, sizeof(ostream)); pb_encode(&ostream, grpc_health_v1_HealthCheckResponse_fields, @@ -108,48 +236,282 @@ Status DefaultHealthCheckService::HealthCheckServiceImpl::Check( GRPC_SLICE_LENGTH(response_slice)); bool encode_status = pb_encode( &ostream, grpc_health_v1_HealthCheckResponse_fields, &response_struct); - if (!encode_status) { - return Status(StatusCode::INTERNAL, "Failed to encode response."); - } + if (!encode_status) return false; Slice encoded_response(response_slice, Slice::STEAL_REF); ByteBuffer response_buffer(&encoded_response, 1); response->Swap(&response_buffer); - return Status::OK; + return true; } -DefaultHealthCheckService::DefaultHealthCheckService() { - services_map_.emplace("", true); +// +// DefaultHealthCheckService::HealthCheckServiceImpl::CheckCallHandler +// + +void DefaultHealthCheckService::HealthCheckServiceImpl::CheckCallHandler:: + CreateAndStart(ServerCompletionQueue* cq, + DefaultHealthCheckService* database, + HealthCheckServiceImpl* service) { + std::shared_ptr<CallHandler> self = + std::make_shared<CheckCallHandler>(cq, database, service); + CheckCallHandler* handler = static_cast<CheckCallHandler*>(self.get()); + { + std::unique_lock<std::mutex> lock(service->cq_shutdown_mu_); + if (service->shutdown_) return; + // Request a Check() call. + handler->next_ = + CallableTag(std::bind(&CheckCallHandler::OnCallReceived, handler, + std::placeholders::_1, std::placeholders::_2), + std::move(self)); + service->RequestAsyncUnary(0, &handler->ctx_, &handler->request_, + &handler->writer_, cq, cq, &handler->next_); + } } -void DefaultHealthCheckService::SetServingStatus( - const grpc::string& service_name, bool serving) { - std::lock_guard<std::mutex> lock(mu_); - services_map_[service_name] = serving; +DefaultHealthCheckService::HealthCheckServiceImpl::CheckCallHandler:: + CheckCallHandler(ServerCompletionQueue* cq, + DefaultHealthCheckService* database, + HealthCheckServiceImpl* service) + : cq_(cq), database_(database), service_(service), writer_(&ctx_) {} + +void DefaultHealthCheckService::HealthCheckServiceImpl::CheckCallHandler:: + OnCallReceived(std::shared_ptr<CallHandler> self, bool ok) { + if (!ok) { + // The value of ok being false means that the server is shutting down. + return; + } + // Spawn a new handler instance to serve the next new client. Every handler + // instance will deallocate itself when it's done. + CreateAndStart(cq_, database_, service_); + // Process request. + gpr_log(GPR_DEBUG, "[HCS %p] Health check started for handler %p", service_, + this); + grpc::string service_name; + grpc::Status status = Status::OK; + ByteBuffer response; + if (!service_->DecodeRequest(request_, &service_name)) { + status = Status(INVALID_ARGUMENT, ""); + } else { + ServingStatus serving_status = database_->GetServingStatus(service_name); + if (serving_status == NOT_FOUND) { + status = Status(StatusCode::NOT_FOUND, "service name unknown"); + } else if (!service_->EncodeResponse(serving_status, &response)) { + status = Status(INTERNAL, ""); + } + } + // Send response. + { + std::unique_lock<std::mutex> lock(service_->cq_shutdown_mu_); + if (!service_->shutdown_) { + next_ = + CallableTag(std::bind(&CheckCallHandler::OnFinishDone, this, + std::placeholders::_1, std::placeholders::_2), + std::move(self)); + if (status.ok()) { + writer_.Finish(response, status, &next_); + } else { + writer_.FinishWithError(status, &next_); + } + } + } } -void DefaultHealthCheckService::SetServingStatus(bool serving) { - std::lock_guard<std::mutex> lock(mu_); - for (auto iter = services_map_.begin(); iter != services_map_.end(); ++iter) { - iter->second = serving; +void DefaultHealthCheckService::HealthCheckServiceImpl::CheckCallHandler:: + OnFinishDone(std::shared_ptr<CallHandler> self, bool ok) { + if (ok) { + gpr_log(GPR_DEBUG, "[HCS %p] Health check call finished for handler %p", + service_, this); } } -DefaultHealthCheckService::ServingStatus -DefaultHealthCheckService::GetServingStatus( - const grpc::string& service_name) const { - std::lock_guard<std::mutex> lock(mu_); - const auto& iter = services_map_.find(service_name); - if (iter == services_map_.end()) { - return NOT_FOUND; +// +// DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler +// + +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + CreateAndStart(ServerCompletionQueue* cq, + DefaultHealthCheckService* database, + HealthCheckServiceImpl* service) { + std::shared_ptr<CallHandler> self = + std::make_shared<WatchCallHandler>(cq, database, service); + WatchCallHandler* handler = static_cast<WatchCallHandler*>(self.get()); + { + std::unique_lock<std::mutex> lock(service->cq_shutdown_mu_); + if (service->shutdown_) return; + // Request AsyncNotifyWhenDone(). + handler->on_done_notified_ = + CallableTag(std::bind(&WatchCallHandler::OnDoneNotified, handler, + std::placeholders::_1, std::placeholders::_2), + self /* copies ref */); + handler->ctx_.AsyncNotifyWhenDone(&handler->on_done_notified_); + // Request a Watch() call. + handler->next_ = + CallableTag(std::bind(&WatchCallHandler::OnCallReceived, handler, + std::placeholders::_1, std::placeholders::_2), + std::move(self)); + service->RequestAsyncServerStreaming(1, &handler->ctx_, &handler->request_, + &handler->stream_, cq, cq, + &handler->next_); } - return iter->second ? SERVING : NOT_SERVING; } -DefaultHealthCheckService::HealthCheckServiceImpl* -DefaultHealthCheckService::GetHealthCheckService() { - GPR_ASSERT(impl_ == nullptr); - impl_.reset(new HealthCheckServiceImpl(this)); - return impl_.get(); +DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + WatchCallHandler(ServerCompletionQueue* cq, + DefaultHealthCheckService* database, + HealthCheckServiceImpl* service) + : cq_(cq), + database_(database), + service_(service), + stream_(&ctx_), + call_state_(WAITING_FOR_CALL) {} + +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + OnCallReceived(std::shared_ptr<CallHandler> self, bool ok) { + if (ok) { + call_state_ = CALL_RECEIVED; + } else { + // AsyncNotifyWhenDone() needs to be called before the call starts, but the + // tag will not pop out if the call never starts ( + // https://github.com/grpc/grpc/issues/10136). So we need to manually + // release the ownership of the handler in this case. + GPR_ASSERT(on_done_notified_.ReleaseHandler() != nullptr); + } + if (!ok || shutdown_) { + // The value of ok being false means that the server is shutting down. + Shutdown(std::move(self), "OnCallReceived"); + return; + } + // Spawn a new handler instance to serve the next new client. Every handler + // instance will deallocate itself when it's done. + CreateAndStart(cq_, database_, service_); + // Parse request. + if (!service_->DecodeRequest(request_, &service_name_)) { + on_finish_done_ = + CallableTag(std::bind(&WatchCallHandler::OnFinishDone, this, + std::placeholders::_1, std::placeholders::_2), + std::move(self)); + stream_.Finish(Status(INVALID_ARGUMENT, ""), &on_finish_done_); + call_state_ = FINISH_CALLED; + return; + } + // Register the call for updates to the service. + gpr_log(GPR_DEBUG, + "[HCS %p] Health check watch started for service \"%s\" " + "(handler: %p)", + service_, service_name_.c_str(), this); + database_->RegisterCallHandler(service_name_, std::move(self)); +} + +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + SendHealth(std::shared_ptr<CallHandler> self, ServingStatus status) { + std::unique_lock<std::mutex> lock(mu_); + // If there's already a send in flight, cache the new status, and + // we'll start a new send for it when the one in flight completes. + if (send_in_flight_) { + pending_status_ = status; + return; + } + // Start a send. + SendHealthLocked(std::move(self), status); +} + +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + SendHealthLocked(std::shared_ptr<CallHandler> self, ServingStatus status) { + std::unique_lock<std::mutex> cq_lock(service_->cq_shutdown_mu_); + if (service_->shutdown_) { + cq_lock.release()->unlock(); + Shutdown(std::move(self), "SendHealthLocked"); + return; + } + send_in_flight_ = true; + call_state_ = SEND_MESSAGE_PENDING; + // Construct response. + ByteBuffer response; + if (!service_->EncodeResponse(status, &response)) { + on_finish_done_ = + CallableTag(std::bind(&WatchCallHandler::OnFinishDone, this, + std::placeholders::_1, std::placeholders::_2), + std::move(self)); + stream_.Finish(Status(INTERNAL, ""), &on_finish_done_); + return; + } + next_ = CallableTag(std::bind(&WatchCallHandler::OnSendHealthDone, this, + std::placeholders::_1, std::placeholders::_2), + std::move(self)); + stream_.Write(response, &next_); +} + +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + OnSendHealthDone(std::shared_ptr<CallHandler> self, bool ok) { + if (!ok || shutdown_) { + Shutdown(std::move(self), "OnSendHealthDone"); + return; + } + call_state_ = CALL_RECEIVED; + { + std::unique_lock<std::mutex> lock(mu_); + send_in_flight_ = false; + // If we got a new status since we started the last send, start a + // new send for it. + if (pending_status_ != NOT_FOUND) { + auto status = pending_status_; + pending_status_ = NOT_FOUND; + SendHealthLocked(std::move(self), status); + } + } +} + +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + OnDoneNotified(std::shared_ptr<CallHandler> self, bool ok) { + GPR_ASSERT(ok); + done_notified_ = true; + if (ctx_.IsCancelled()) { + is_cancelled_ = true; + } + gpr_log(GPR_DEBUG, + "[HCS %p] Healt check call is notified done (handler: %p, " + "is_cancelled: %d).", + service_, this, static_cast<int>(is_cancelled_)); + Shutdown(std::move(self), "OnDoneNotified"); +} + +// TODO(roth): This method currently assumes that there will be only one +// thread polling the cq and invoking the corresponding callbacks. If +// that changes, we will need to add synchronization here. +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + Shutdown(std::shared_ptr<CallHandler> self, const char* reason) { + if (!shutdown_) { + gpr_log(GPR_DEBUG, + "[HCS %p] Shutting down the handler (service_name: \"%s\", " + "handler: %p, reason: %s).", + service_, service_name_.c_str(), this, reason); + shutdown_ = true; + } + // OnCallReceived() may be called after OnDoneNotified(), so we need to + // try to Finish() every time we are in Shutdown(). + if (call_state_ >= CALL_RECEIVED && call_state_ < FINISH_CALLED) { + std::unique_lock<std::mutex> lock(service_->cq_shutdown_mu_); + if (!service_->shutdown_) { + on_finish_done_ = + CallableTag(std::bind(&WatchCallHandler::OnFinishDone, this, + std::placeholders::_1, std::placeholders::_2), + std::move(self)); + // TODO(juanlishen): Maybe add a message proto for the client to + // explicitly cancel the stream so that we can return OK status in such + // cases. + stream_.Finish(Status::CANCELLED, &on_finish_done_); + call_state_ = FINISH_CALLED; + } + } +} + +void DefaultHealthCheckService::HealthCheckServiceImpl::WatchCallHandler:: + OnFinishDone(std::shared_ptr<CallHandler> self, bool ok) { + if (ok) { + gpr_log(GPR_DEBUG, + "[HCS %p] Health check call finished (service_name: \"%s\", " + "handler: %p).", + service_, service_name_.c_str(), this); + } } } // namespace grpc |