| /* |
| * |
| * Copyright 2018 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 <grpc/support/port_platform.h> |
| |
| #include <stdint.h> |
| #include <stdio.h> |
| |
| #include "src/core/ext/filters/client_channel/health/health_check_client.h" |
| |
| #include "pb_decode.h" |
| #include "pb_encode.h" |
| #include "src/core/ext/filters/client_channel/health/health.pb.h" |
| #include "src/core/lib/debug/trace.h" |
| #include "src/core/lib/gprpp/sync.h" |
| #include "src/core/lib/slice/slice_internal.h" |
| #include "src/core/lib/transport/error_utils.h" |
| #include "src/core/lib/transport/status_metadata.h" |
| |
| #define HEALTH_CHECK_INITIAL_CONNECT_BACKOFF_SECONDS 1 |
| #define HEALTH_CHECK_RECONNECT_BACKOFF_MULTIPLIER 1.6 |
| #define HEALTH_CHECK_RECONNECT_MAX_BACKOFF_SECONDS 120 |
| #define HEALTH_CHECK_RECONNECT_JITTER 0.2 |
| |
| namespace grpc_core { |
| |
| TraceFlag grpc_health_check_client_trace(false, "health_check_client"); |
| |
| // |
| // HealthCheckClient |
| // |
| |
| HealthCheckClient::HealthCheckClient( |
| const char* service_name, |
| RefCountedPtr<ConnectedSubchannel> connected_subchannel, |
| grpc_pollset_set* interested_parties, |
| RefCountedPtr<channelz::SubchannelNode> channelz_node) |
| : InternallyRefCounted<HealthCheckClient>(&grpc_health_check_client_trace), |
| service_name_(service_name), |
| connected_subchannel_(std::move(connected_subchannel)), |
| interested_parties_(interested_parties), |
| channelz_node_(std::move(channelz_node)), |
| retry_backoff_( |
| BackOff::Options() |
| .set_initial_backoff( |
| HEALTH_CHECK_INITIAL_CONNECT_BACKOFF_SECONDS * 1000) |
| .set_multiplier(HEALTH_CHECK_RECONNECT_BACKOFF_MULTIPLIER) |
| .set_jitter(HEALTH_CHECK_RECONNECT_JITTER) |
| .set_max_backoff(HEALTH_CHECK_RECONNECT_MAX_BACKOFF_SECONDS * |
| 1000)) { |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "created HealthCheckClient %p", this); |
| } |
| GRPC_CLOSURE_INIT(&retry_timer_callback_, OnRetryTimer, this, |
| grpc_schedule_on_exec_ctx); |
| StartCall(); |
| } |
| |
| HealthCheckClient::~HealthCheckClient() { |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "destroying HealthCheckClient %p", this); |
| } |
| GRPC_ERROR_UNREF(error_); |
| } |
| |
| void HealthCheckClient::NotifyOnHealthChange(grpc_connectivity_state* state, |
| grpc_closure* closure) { |
| MutexLock lock(&mu_); |
| GPR_ASSERT(notify_state_ == nullptr); |
| if (*state != state_) { |
| *state = state_; |
| GRPC_CLOSURE_SCHED(closure, GRPC_ERROR_REF(error_)); |
| return; |
| } |
| notify_state_ = state; |
| on_health_changed_ = closure; |
| } |
| |
| void HealthCheckClient::SetHealthStatus(grpc_connectivity_state state, |
| grpc_error* error) { |
| MutexLock lock(&mu_); |
| SetHealthStatusLocked(state, error); |
| } |
| |
| void HealthCheckClient::SetHealthStatusLocked(grpc_connectivity_state state, |
| grpc_error* error) { |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "HealthCheckClient %p: setting state=%d error=%s", this, |
| state, grpc_error_string(error)); |
| } |
| if (notify_state_ != nullptr && *notify_state_ != state) { |
| *notify_state_ = state; |
| notify_state_ = nullptr; |
| GRPC_CLOSURE_SCHED(on_health_changed_, GRPC_ERROR_REF(error)); |
| on_health_changed_ = nullptr; |
| } |
| state_ = state; |
| GRPC_ERROR_UNREF(error_); |
| error_ = error; |
| } |
| |
| void HealthCheckClient::Orphan() { |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "HealthCheckClient %p: shutting down", this); |
| } |
| { |
| MutexLock lock(&mu_); |
| if (on_health_changed_ != nullptr) { |
| *notify_state_ = GRPC_CHANNEL_SHUTDOWN; |
| notify_state_ = nullptr; |
| GRPC_CLOSURE_SCHED(on_health_changed_, GRPC_ERROR_NONE); |
| on_health_changed_ = nullptr; |
| } |
| shutting_down_ = true; |
| call_state_.reset(); |
| if (retry_timer_callback_pending_) { |
| grpc_timer_cancel(&retry_timer_); |
| } |
| } |
| Unref(DEBUG_LOCATION, "orphan"); |
| } |
| |
| void HealthCheckClient::StartCall() { |
| MutexLock lock(&mu_); |
| StartCallLocked(); |
| } |
| |
| void HealthCheckClient::StartCallLocked() { |
| if (shutting_down_) return; |
| GPR_ASSERT(call_state_ == nullptr); |
| SetHealthStatusLocked(GRPC_CHANNEL_CONNECTING, GRPC_ERROR_NONE); |
| call_state_ = MakeOrphanable<CallState>(Ref(), interested_parties_); |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "HealthCheckClient %p: created CallState %p", this, |
| call_state_.get()); |
| } |
| call_state_->StartCall(); |
| } |
| |
| void HealthCheckClient::StartRetryTimer() { |
| MutexLock lock(&mu_); |
| SetHealthStatusLocked( |
| GRPC_CHANNEL_TRANSIENT_FAILURE, |
| GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "health check call failed; will retry after backoff")); |
| grpc_millis next_try = retry_backoff_.NextAttemptTime(); |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "HealthCheckClient %p: health check call lost...", this); |
| grpc_millis timeout = next_try - ExecCtx::Get()->Now(); |
| if (timeout > 0) { |
| gpr_log(GPR_INFO, |
| "HealthCheckClient %p: ... will retry in %" PRId64 "ms.", this, |
| timeout); |
| } else { |
| gpr_log(GPR_INFO, "HealthCheckClient %p: ... retrying immediately.", |
| this); |
| } |
| } |
| // Ref for callback, tracked manually. |
| Ref(DEBUG_LOCATION, "health_retry_timer").release(); |
| retry_timer_callback_pending_ = true; |
| grpc_timer_init(&retry_timer_, next_try, &retry_timer_callback_); |
| } |
| |
| void HealthCheckClient::OnRetryTimer(void* arg, grpc_error* error) { |
| HealthCheckClient* self = static_cast<HealthCheckClient*>(arg); |
| { |
| MutexLock lock(&self->mu_); |
| self->retry_timer_callback_pending_ = false; |
| if (!self->shutting_down_ && error == GRPC_ERROR_NONE && |
| self->call_state_ == nullptr) { |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "HealthCheckClient %p: restarting health check call", |
| self); |
| } |
| self->StartCallLocked(); |
| } |
| } |
| self->Unref(DEBUG_LOCATION, "health_retry_timer"); |
| } |
| |
| // |
| // protobuf helpers |
| // |
| |
| namespace { |
| |
| void EncodeRequest(const char* service_name, |
| ManualConstructor<SliceBufferByteStream>* send_message) { |
| grpc_health_v1_HealthCheckRequest request_struct; |
| request_struct.has_service = true; |
| snprintf(request_struct.service, sizeof(request_struct.service), "%s", |
| service_name); |
| pb_ostream_t ostream; |
| memset(&ostream, 0, sizeof(ostream)); |
| pb_encode(&ostream, grpc_health_v1_HealthCheckRequest_fields, |
| &request_struct); |
| grpc_slice request_slice = GRPC_SLICE_MALLOC(ostream.bytes_written); |
| ostream = pb_ostream_from_buffer(GRPC_SLICE_START_PTR(request_slice), |
| GRPC_SLICE_LENGTH(request_slice)); |
| GPR_ASSERT(pb_encode(&ostream, grpc_health_v1_HealthCheckRequest_fields, |
| &request_struct) != 0); |
| grpc_slice_buffer slice_buffer; |
| grpc_slice_buffer_init(&slice_buffer); |
| grpc_slice_buffer_add(&slice_buffer, request_slice); |
| send_message->Init(&slice_buffer, 0); |
| grpc_slice_buffer_destroy_internal(&slice_buffer); |
| } |
| |
| // Returns true if healthy. |
| // If there was an error parsing the response, sets *error and returns false. |
| bool DecodeResponse(grpc_slice_buffer* slice_buffer, grpc_error** error) { |
| // If message is empty, assume unhealthy. |
| if (slice_buffer->length == 0) { |
| *error = |
| GRPC_ERROR_CREATE_FROM_STATIC_STRING("health check response was empty"); |
| return false; |
| } |
| // Concatenate the slices to form a single string. |
| UniquePtr<uint8_t> recv_message_deleter; |
| uint8_t* recv_message; |
| if (slice_buffer->count == 1) { |
| recv_message = GRPC_SLICE_START_PTR(slice_buffer->slices[0]); |
| } else { |
| recv_message = static_cast<uint8_t*>(gpr_malloc(slice_buffer->length)); |
| recv_message_deleter.reset(recv_message); |
| size_t offset = 0; |
| for (size_t i = 0; i < slice_buffer->count; ++i) { |
| memcpy(recv_message + offset, |
| GRPC_SLICE_START_PTR(slice_buffer->slices[i]), |
| GRPC_SLICE_LENGTH(slice_buffer->slices[i])); |
| offset += GRPC_SLICE_LENGTH(slice_buffer->slices[i]); |
| } |
| } |
| // Deserialize message. |
| grpc_health_v1_HealthCheckResponse response_struct; |
| pb_istream_t istream = |
| pb_istream_from_buffer(recv_message, slice_buffer->length); |
| if (!pb_decode(&istream, grpc_health_v1_HealthCheckResponse_fields, |
| &response_struct)) { |
| // Can't parse message; assume unhealthy. |
| *error = GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "cannot parse health check response"); |
| return false; |
| } |
| if (!response_struct.has_status) { |
| // Field not present; assume unhealthy. |
| *error = GRPC_ERROR_CREATE_FROM_STATIC_STRING( |
| "status field not present in health check response"); |
| return false; |
| } |
| return response_struct.status == |
| grpc_health_v1_HealthCheckResponse_ServingStatus_SERVING; |
| } |
| |
| } // namespace |
| |
| // |
| // HealthCheckClient::CallState |
| // |
| |
| HealthCheckClient::CallState::CallState( |
| RefCountedPtr<HealthCheckClient> health_check_client, |
| grpc_pollset_set* interested_parties) |
| : health_check_client_(std::move(health_check_client)), |
| pollent_(grpc_polling_entity_create_from_pollset_set(interested_parties)), |
| arena_(Arena::Create(health_check_client_->connected_subchannel_ |
| ->GetInitialCallSizeEstimate(0))), |
| payload_(context_) {} |
| |
| HealthCheckClient::CallState::~CallState() { |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, "HealthCheckClient %p: destroying CallState %p", |
| health_check_client_.get(), this); |
| } |
| for (size_t i = 0; i < GRPC_CONTEXT_COUNT; i++) { |
| if (context_[i].destroy != nullptr) { |
| context_[i].destroy(context_[i].value); |
| } |
| } |
| // Unset the call combiner cancellation closure. This has the |
| // effect of scheduling the previously set cancellation closure, if |
| // any, so that it can release any internal references it may be |
| // holding to the call stack. Also flush the closures on exec_ctx so that |
| // filters that schedule cancel notification closures on exec_ctx do not |
| // need to take a ref of the call stack to guarantee closure liveness. |
| call_combiner_.SetNotifyOnCancel(nullptr); |
| ExecCtx::Get()->Flush(); |
| arena_->Destroy(); |
| } |
| |
| void HealthCheckClient::CallState::Orphan() { |
| call_combiner_.Cancel(GRPC_ERROR_CANCELLED); |
| Cancel(); |
| } |
| |
| void HealthCheckClient::CallState::StartCall() { |
| SubchannelCall::Args args = { |
| health_check_client_->connected_subchannel_, |
| &pollent_, |
| GRPC_MDSTR_SLASH_GRPC_DOT_HEALTH_DOT_V1_DOT_HEALTH_SLASH_WATCH, |
| gpr_now(GPR_CLOCK_MONOTONIC), // start_time |
| GRPC_MILLIS_INF_FUTURE, // deadline |
| arena_, |
| context_, |
| &call_combiner_, |
| 0, // parent_data_size |
| }; |
| grpc_error* error = GRPC_ERROR_NONE; |
| call_ = SubchannelCall::Create(std::move(args), &error).release(); |
| // Register after-destruction callback. |
| GRPC_CLOSURE_INIT(&after_call_stack_destruction_, AfterCallStackDestruction, |
| this, grpc_schedule_on_exec_ctx); |
| call_->SetAfterCallStackDestroy(&after_call_stack_destruction_); |
| // Check if creation failed. |
| if (error != GRPC_ERROR_NONE) { |
| gpr_log(GPR_ERROR, |
| "HealthCheckClient %p CallState %p: error creating health " |
| "checking call on subchannel (%s); will retry", |
| health_check_client_.get(), this, grpc_error_string(error)); |
| GRPC_ERROR_UNREF(error); |
| // Schedule instead of running directly, since we must not be |
| // holding health_check_client_->mu_ when CallEnded() is called. |
| call_->Ref(DEBUG_LOCATION, "call_end_closure").release(); |
| GRPC_CLOSURE_SCHED( |
| GRPC_CLOSURE_INIT(&batch_.handler_private.closure, CallEndedRetry, this, |
| grpc_schedule_on_exec_ctx), |
| GRPC_ERROR_NONE); |
| return; |
| } |
| // Initialize payload and batch. |
| payload_.context = context_; |
| batch_.payload = &payload_; |
| // on_complete callback takes ref, handled manually. |
| call_->Ref(DEBUG_LOCATION, "on_complete").release(); |
| batch_.on_complete = GRPC_CLOSURE_INIT(&on_complete_, OnComplete, this, |
| grpc_schedule_on_exec_ctx); |
| // Add send_initial_metadata op. |
| grpc_metadata_batch_init(&send_initial_metadata_); |
| error = grpc_metadata_batch_add_head( |
| &send_initial_metadata_, &path_metadata_storage_, |
| grpc_mdelem_from_slices( |
| GRPC_MDSTR_PATH, |
| GRPC_MDSTR_SLASH_GRPC_DOT_HEALTH_DOT_V1_DOT_HEALTH_SLASH_WATCH)); |
| GPR_ASSERT(error == GRPC_ERROR_NONE); |
| payload_.send_initial_metadata.send_initial_metadata = |
| &send_initial_metadata_; |
| payload_.send_initial_metadata.send_initial_metadata_flags = 0; |
| payload_.send_initial_metadata.peer_string = nullptr; |
| batch_.send_initial_metadata = true; |
| // Add send_message op. |
| EncodeRequest(health_check_client_->service_name_, &send_message_); |
| payload_.send_message.send_message.reset(send_message_.get()); |
| batch_.send_message = true; |
| // Add send_trailing_metadata op. |
| grpc_metadata_batch_init(&send_trailing_metadata_); |
| payload_.send_trailing_metadata.send_trailing_metadata = |
| &send_trailing_metadata_; |
| batch_.send_trailing_metadata = true; |
| // Add recv_initial_metadata op. |
| grpc_metadata_batch_init(&recv_initial_metadata_); |
| payload_.recv_initial_metadata.recv_initial_metadata = |
| &recv_initial_metadata_; |
| payload_.recv_initial_metadata.recv_flags = nullptr; |
| payload_.recv_initial_metadata.trailing_metadata_available = nullptr; |
| payload_.recv_initial_metadata.peer_string = nullptr; |
| // recv_initial_metadata_ready callback takes ref, handled manually. |
| call_->Ref(DEBUG_LOCATION, "recv_initial_metadata_ready").release(); |
| payload_.recv_initial_metadata.recv_initial_metadata_ready = |
| GRPC_CLOSURE_INIT(&recv_initial_metadata_ready_, RecvInitialMetadataReady, |
| this, grpc_schedule_on_exec_ctx); |
| batch_.recv_initial_metadata = true; |
| // Add recv_message op. |
| payload_.recv_message.recv_message = &recv_message_; |
| // recv_message callback takes ref, handled manually. |
| call_->Ref(DEBUG_LOCATION, "recv_message_ready").release(); |
| payload_.recv_message.recv_message_ready = GRPC_CLOSURE_INIT( |
| &recv_message_ready_, RecvMessageReady, this, grpc_schedule_on_exec_ctx); |
| batch_.recv_message = true; |
| // Start batch. |
| StartBatch(&batch_); |
| // Initialize recv_trailing_metadata batch. |
| recv_trailing_metadata_batch_.payload = &payload_; |
| // Add recv_trailing_metadata op. |
| grpc_metadata_batch_init(&recv_trailing_metadata_); |
| payload_.recv_trailing_metadata.recv_trailing_metadata = |
| &recv_trailing_metadata_; |
| payload_.recv_trailing_metadata.collect_stats = &collect_stats_; |
| // This callback signals the end of the call, so it relies on the |
| // initial ref instead of taking a new ref. When it's invoked, the |
| // initial ref is released. |
| payload_.recv_trailing_metadata.recv_trailing_metadata_ready = |
| GRPC_CLOSURE_INIT(&recv_trailing_metadata_ready_, |
| RecvTrailingMetadataReady, this, |
| grpc_schedule_on_exec_ctx); |
| recv_trailing_metadata_batch_.recv_trailing_metadata = true; |
| // Start recv_trailing_metadata batch. |
| StartBatch(&recv_trailing_metadata_batch_); |
| } |
| |
| void HealthCheckClient::CallState::StartBatchInCallCombiner(void* arg, |
| grpc_error* error) { |
| grpc_transport_stream_op_batch* batch = |
| static_cast<grpc_transport_stream_op_batch*>(arg); |
| SubchannelCall* call = |
| static_cast<SubchannelCall*>(batch->handler_private.extra_arg); |
| call->StartTransportStreamOpBatch(batch); |
| } |
| |
| void HealthCheckClient::CallState::StartBatch( |
| grpc_transport_stream_op_batch* batch) { |
| batch->handler_private.extra_arg = call_; |
| GRPC_CLOSURE_INIT(&batch->handler_private.closure, StartBatchInCallCombiner, |
| batch, grpc_schedule_on_exec_ctx); |
| GRPC_CALL_COMBINER_START(&call_combiner_, &batch->handler_private.closure, |
| GRPC_ERROR_NONE, "start_subchannel_batch"); |
| } |
| |
| void HealthCheckClient::CallState::AfterCallStackDestruction( |
| void* arg, grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| Delete(self); |
| } |
| |
| void HealthCheckClient::CallState::OnCancelComplete(void* arg, |
| grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| GRPC_CALL_COMBINER_STOP(&self->call_combiner_, "health_cancel"); |
| self->call_->Unref(DEBUG_LOCATION, "cancel"); |
| } |
| |
| void HealthCheckClient::CallState::StartCancel(void* arg, grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| auto* batch = grpc_make_transport_stream_op( |
| GRPC_CLOSURE_CREATE(OnCancelComplete, self, grpc_schedule_on_exec_ctx)); |
| batch->cancel_stream = true; |
| batch->payload->cancel_stream.cancel_error = GRPC_ERROR_CANCELLED; |
| self->call_->StartTransportStreamOpBatch(batch); |
| } |
| |
| void HealthCheckClient::CallState::Cancel() { |
| bool expected = false; |
| if (cancelled_.CompareExchangeStrong(&expected, true, MemoryOrder::ACQ_REL, |
| MemoryOrder::ACQUIRE)) { |
| call_->Ref(DEBUG_LOCATION, "cancel").release(); |
| GRPC_CALL_COMBINER_START( |
| &call_combiner_, |
| GRPC_CLOSURE_CREATE(StartCancel, this, grpc_schedule_on_exec_ctx), |
| GRPC_ERROR_NONE, "health_cancel"); |
| } |
| } |
| |
| void HealthCheckClient::CallState::OnComplete(void* arg, grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| GRPC_CALL_COMBINER_STOP(&self->call_combiner_, "on_complete"); |
| grpc_metadata_batch_destroy(&self->send_initial_metadata_); |
| grpc_metadata_batch_destroy(&self->send_trailing_metadata_); |
| self->call_->Unref(DEBUG_LOCATION, "on_complete"); |
| } |
| |
| void HealthCheckClient::CallState::RecvInitialMetadataReady(void* arg, |
| grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| GRPC_CALL_COMBINER_STOP(&self->call_combiner_, "recv_initial_metadata_ready"); |
| grpc_metadata_batch_destroy(&self->recv_initial_metadata_); |
| self->call_->Unref(DEBUG_LOCATION, "recv_initial_metadata_ready"); |
| } |
| |
| void HealthCheckClient::CallState::DoneReadingRecvMessage(grpc_error* error) { |
| recv_message_.reset(); |
| if (error != GRPC_ERROR_NONE) { |
| GRPC_ERROR_UNREF(error); |
| Cancel(); |
| grpc_slice_buffer_destroy_internal(&recv_message_buffer_); |
| call_->Unref(DEBUG_LOCATION, "recv_message_ready"); |
| return; |
| } |
| const bool healthy = DecodeResponse(&recv_message_buffer_, &error); |
| const grpc_connectivity_state state = |
| healthy ? GRPC_CHANNEL_READY : GRPC_CHANNEL_TRANSIENT_FAILURE; |
| if (error == GRPC_ERROR_NONE && !healthy) { |
| error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("backend unhealthy"); |
| } |
| health_check_client_->SetHealthStatus(state, error); |
| seen_response_.Store(true, MemoryOrder::RELEASE); |
| grpc_slice_buffer_destroy_internal(&recv_message_buffer_); |
| // Start another recv_message batch. |
| // This re-uses the ref we're holding. |
| // Note: Can't just reuse batch_ here, since we don't know that all |
| // callbacks from the original batch have completed yet. |
| recv_message_batch_.payload = &payload_; |
| payload_.recv_message.recv_message = &recv_message_; |
| payload_.recv_message.recv_message_ready = GRPC_CLOSURE_INIT( |
| &recv_message_ready_, RecvMessageReady, this, grpc_schedule_on_exec_ctx); |
| recv_message_batch_.recv_message = true; |
| StartBatch(&recv_message_batch_); |
| } |
| |
| grpc_error* HealthCheckClient::CallState::PullSliceFromRecvMessage() { |
| grpc_slice slice; |
| grpc_error* error = recv_message_->Pull(&slice); |
| if (error == GRPC_ERROR_NONE) { |
| grpc_slice_buffer_add(&recv_message_buffer_, slice); |
| } |
| return error; |
| } |
| |
| void HealthCheckClient::CallState::ContinueReadingRecvMessage() { |
| while (recv_message_->Next(SIZE_MAX, &recv_message_ready_)) { |
| grpc_error* error = PullSliceFromRecvMessage(); |
| if (error != GRPC_ERROR_NONE) { |
| DoneReadingRecvMessage(error); |
| return; |
| } |
| if (recv_message_buffer_.length == recv_message_->length()) { |
| DoneReadingRecvMessage(GRPC_ERROR_NONE); |
| break; |
| } |
| } |
| } |
| |
| void HealthCheckClient::CallState::OnByteStreamNext(void* arg, |
| grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| if (error != GRPC_ERROR_NONE) { |
| self->DoneReadingRecvMessage(GRPC_ERROR_REF(error)); |
| return; |
| } |
| error = self->PullSliceFromRecvMessage(); |
| if (error != GRPC_ERROR_NONE) { |
| self->DoneReadingRecvMessage(error); |
| return; |
| } |
| if (self->recv_message_buffer_.length == self->recv_message_->length()) { |
| self->DoneReadingRecvMessage(GRPC_ERROR_NONE); |
| } else { |
| self->ContinueReadingRecvMessage(); |
| } |
| } |
| |
| void HealthCheckClient::CallState::RecvMessageReady(void* arg, |
| grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| GRPC_CALL_COMBINER_STOP(&self->call_combiner_, "recv_message_ready"); |
| if (self->recv_message_ == nullptr) { |
| self->call_->Unref(DEBUG_LOCATION, "recv_message_ready"); |
| return; |
| } |
| grpc_slice_buffer_init(&self->recv_message_buffer_); |
| GRPC_CLOSURE_INIT(&self->recv_message_ready_, OnByteStreamNext, self, |
| grpc_schedule_on_exec_ctx); |
| self->ContinueReadingRecvMessage(); |
| // Ref will continue to be held until we finish draining the byte stream. |
| } |
| |
| void HealthCheckClient::CallState::RecvTrailingMetadataReady( |
| void* arg, grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| GRPC_CALL_COMBINER_STOP(&self->call_combiner_, |
| "recv_trailing_metadata_ready"); |
| // Get call status. |
| grpc_status_code status = GRPC_STATUS_UNKNOWN; |
| if (error != GRPC_ERROR_NONE) { |
| grpc_error_get_status(error, GRPC_MILLIS_INF_FUTURE, &status, |
| nullptr /* slice */, nullptr /* http_error */, |
| nullptr /* error_string */); |
| } else if (self->recv_trailing_metadata_.idx.named.grpc_status != nullptr) { |
| status = grpc_get_status_code_from_metadata( |
| self->recv_trailing_metadata_.idx.named.grpc_status->md); |
| } |
| if (GRPC_TRACE_FLAG_ENABLED(grpc_health_check_client_trace)) { |
| gpr_log(GPR_INFO, |
| "HealthCheckClient %p CallState %p: health watch failed with " |
| "status %d", |
| self->health_check_client_.get(), self, status); |
| } |
| // Clean up. |
| grpc_metadata_batch_destroy(&self->recv_trailing_metadata_); |
| // For status UNIMPLEMENTED, give up and assume always healthy. |
| bool retry = true; |
| if (status == GRPC_STATUS_UNIMPLEMENTED) { |
| static const char kErrorMessage[] = |
| "health checking Watch method returned UNIMPLEMENTED; " |
| "disabling health checks but assuming server is healthy"; |
| gpr_log(GPR_ERROR, kErrorMessage); |
| if (self->health_check_client_->channelz_node_ != nullptr) { |
| self->health_check_client_->channelz_node_->AddTraceEvent( |
| channelz::ChannelTrace::Error, |
| grpc_slice_from_static_string(kErrorMessage)); |
| } |
| self->health_check_client_->SetHealthStatus(GRPC_CHANNEL_READY, |
| GRPC_ERROR_NONE); |
| retry = false; |
| } |
| self->CallEnded(retry); |
| } |
| |
| void HealthCheckClient::CallState::CallEndedRetry(void* arg, |
| grpc_error* error) { |
| HealthCheckClient::CallState* self = |
| static_cast<HealthCheckClient::CallState*>(arg); |
| self->CallEnded(true /* retry */); |
| self->call_->Unref(DEBUG_LOCATION, "call_end_closure"); |
| } |
| |
| void HealthCheckClient::CallState::CallEnded(bool retry) { |
| // If this CallState is still in use, this call ended because of a failure, |
| // so we need to stop using it and optionally create a new one. |
| // Otherwise, we have deliberately ended this call, and no further action |
| // is required. |
| if (this == health_check_client_->call_state_.get()) { |
| health_check_client_->call_state_.reset(); |
| if (retry) { |
| GPR_ASSERT(!health_check_client_->shutting_down_); |
| if (seen_response_.Load(MemoryOrder::ACQUIRE)) { |
| // If the call fails after we've gotten a successful response, reset |
| // the backoff and restart the call immediately. |
| health_check_client_->retry_backoff_.Reset(); |
| health_check_client_->StartCall(); |
| } else { |
| // If the call failed without receiving any messages, retry later. |
| health_check_client_->StartRetryTimer(); |
| } |
| } |
| } |
| // When the last ref to the call stack goes away, the CallState object |
| // will be automatically destroyed. |
| call_->Unref(DEBUG_LOCATION, "call_ended"); |
| } |
| |
| } // namespace grpc_core |
