| /* |
| * |
| * Copyright 2015 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. |
| * |
| */ |
| |
| #ifndef GRPCXX_IMPL_CODEGEN_ASYNC_UNARY_CALL_H |
| #define GRPCXX_IMPL_CODEGEN_ASYNC_UNARY_CALL_H |
| |
| #include <assert.h> |
| #include <grpc++/impl/codegen/call.h> |
| #include <grpc++/impl/codegen/channel_interface.h> |
| #include <grpc++/impl/codegen/client_context.h> |
| #include <grpc++/impl/codegen/server_context.h> |
| #include <grpc++/impl/codegen/service_type.h> |
| #include <grpc++/impl/codegen/status.h> |
| |
| namespace grpc { |
| |
| class CompletionQueue; |
| extern CoreCodegenInterface* g_core_codegen_interface; |
| |
| /// An interface relevant for async client side unary RPCS (which send |
| /// one request message to a server and receive one response message). |
| template <class R> |
| class ClientAsyncResponseReaderInterface { |
| public: |
| virtual ~ClientAsyncResponseReaderInterface() {} |
| |
| /// Request notification of the reading of initial metadata. Completion |
| /// will be notified by \a tag on the associated completion queue. |
| /// This call is optional, but if it is used, it cannot be used concurrently |
| /// with or after the \a Finish method. |
| /// |
| /// \param[in] tag Tag identifying this request. |
| virtual void ReadInitialMetadata(void* tag) = 0; |
| |
| /// Request to receive the server's response \a msg and final \a status for |
| /// the call, and to notify \a tag on this call's completion queue when |
| /// finished. |
| /// |
| /// This function will return when either: |
| /// - when the server's response message and status have been received. |
| /// - when the server has returned a non-OK status (no message expected in |
| /// this case). |
| /// - when the call failed for some reason and the library generated a |
| /// non-OK status. |
| /// |
| /// \param[in] tag Tag identifying this request. |
| /// \param[out] status To be updated with the operation status. |
| /// \param[out] msg To be filled in with the server's response message. |
| virtual void Finish(R* msg, Status* status, void* tag) = 0; |
| }; |
| |
| /// Async API for client-side unary RPCs, where the message response |
| /// received from the server is of type \a R. |
| template <class R> |
| class ClientAsyncResponseReader final |
| : public ClientAsyncResponseReaderInterface<R> { |
| public: |
| /// Start a call and write the request out. |
| /// \a tag will be notified on \a cq when the call has been started (i.e. |
| /// intitial metadata sent) and \a request has been written out. |
| /// Note that \a context will be used to fill in custom initial metadata |
| /// used to send to the server when starting the call. |
| template <class W> |
| static ClientAsyncResponseReader* Create(ChannelInterface* channel, |
| CompletionQueue* cq, |
| const RpcMethod& method, |
| ClientContext* context, |
| const W& request) { |
| Call call = channel->CreateCall(method, context, cq); |
| return new (g_core_codegen_interface->grpc_call_arena_alloc( |
| call.call(), sizeof(ClientAsyncResponseReader))) |
| ClientAsyncResponseReader(call, context, request); |
| } |
| |
| /// TODO(vjpai): Delete the below constructor |
| /// PLEASE DO NOT USE THIS CONSTRUCTOR IN NEW CODE |
| /// This code is only present as a short-term workaround |
| /// for users that bypassed the code-generator and directly |
| /// created this struct rather than properly using a stub. |
| /// This code will not remain a valid public constructor for long. |
| template <class W> |
| ClientAsyncResponseReader(ChannelInterface* channel, CompletionQueue* cq, |
| const RpcMethod& method, ClientContext* context, |
| const W& request) |
| : context_(context), |
| call_(channel->CreateCall(method, context, cq)), |
| collection_(std::make_shared<Ops>()) { |
| collection_->init_buf.SetCollection(collection_); |
| collection_->init_buf.SendInitialMetadata( |
| context->send_initial_metadata_, context->initial_metadata_flags()); |
| // TODO(ctiller): don't assert |
| GPR_CODEGEN_ASSERT(collection_->init_buf.SendMessage(request).ok()); |
| collection_->init_buf.ClientSendClose(); |
| call_.PerformOps(&collection_->init_buf); |
| } |
| |
| // always allocated against a call arena, no memory free required |
| static void operator delete(void* ptr, std::size_t size) { |
| assert(size == sizeof(ClientAsyncResponseReader)); |
| } |
| |
| /// See \a ClientAsyncResponseReaderInterface::ReadInitialMetadata for |
| /// semantics. |
| /// |
| /// Side effect: |
| /// - the \a ClientContext associated with this call is updated with |
| /// possible initial and trailing metadata sent from the serve. |
| void ReadInitialMetadata(void* tag) { |
| GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_); |
| |
| Ops* o = &ops_; |
| |
| // TODO(vjpai): Remove the collection_ specialization as soon |
| // as the public constructor is deleted |
| if (collection_) { |
| o = collection_.get(); |
| collection_->meta_buf.SetCollection(collection_); |
| } |
| |
| o->meta_buf.set_output_tag(tag); |
| o->meta_buf.RecvInitialMetadata(context_); |
| call_.PerformOps(&o->meta_buf); |
| } |
| |
| /// See \a ClientAysncResponseReaderInterface::Finish for semantics. |
| /// |
| /// Side effect: |
| /// - the \a ClientContext associated with this call is updated with |
| /// possible initial and trailing metadata sent from the server. |
| void Finish(R* msg, Status* status, void* tag) { |
| Ops* o = &ops_; |
| |
| // TODO(vjpai): Remove the collection_ specialization as soon |
| // as the public constructor is deleted |
| if (collection_) { |
| o = collection_.get(); |
| collection_->finish_buf.SetCollection(collection_); |
| } |
| |
| o->finish_buf.set_output_tag(tag); |
| if (!context_->initial_metadata_received_) { |
| o->finish_buf.RecvInitialMetadata(context_); |
| } |
| o->finish_buf.RecvMessage(msg); |
| o->finish_buf.AllowNoMessage(); |
| o->finish_buf.ClientRecvStatus(context_, status); |
| call_.PerformOps(&o->finish_buf); |
| } |
| |
| private: |
| ClientContext* const context_; |
| Call call_; |
| |
| template <class W> |
| ClientAsyncResponseReader(Call call, ClientContext* context, const W& request) |
| : context_(context), call_(call) { |
| ops_.init_buf.SendInitialMetadata(context->send_initial_metadata_, |
| context->initial_metadata_flags()); |
| // TODO(ctiller): don't assert |
| GPR_CODEGEN_ASSERT(ops_.init_buf.SendMessage(request).ok()); |
| ops_.init_buf.ClientSendClose(); |
| call_.PerformOps(&ops_.init_buf); |
| } |
| |
| // disable operator new |
| static void* operator new(std::size_t size); |
| static void* operator new(std::size_t size, void* p) { return p; } |
| |
| // TODO(vjpai): Remove the reference to CallOpSetCollectionInterface |
| // as soon as the related workaround (public constructor) is deleted |
| struct Ops : public CallOpSetCollectionInterface { |
| SneakyCallOpSet<CallOpSendInitialMetadata, CallOpSendMessage, |
| CallOpClientSendClose> |
| init_buf; |
| CallOpSet<CallOpRecvInitialMetadata> meta_buf; |
| CallOpSet<CallOpRecvInitialMetadata, CallOpRecvMessage<R>, |
| CallOpClientRecvStatus> |
| finish_buf; |
| } ops_; |
| |
| // TODO(vjpai): Remove the collection_ as soon as the related workaround |
| // (public constructor) is deleted |
| std::shared_ptr<Ops> collection_; |
| }; |
| |
| /// Async server-side API for handling unary calls, where the single |
| /// response message sent to the client is of type \a W. |
| template <class W> |
| class ServerAsyncResponseWriter final : public ServerAsyncStreamingInterface { |
| public: |
| explicit ServerAsyncResponseWriter(ServerContext* ctx) |
| : call_(nullptr, nullptr, nullptr), ctx_(ctx) {} |
| |
| /// See \a ServerAsyncStreamingInterface::SendInitialMetadata for semantics. |
| /// |
| /// Side effect: |
| /// The initial metadata that will be sent to the client from this op will |
| /// be taken from the \a ServerContext associated with the call. |
| /// |
| /// \param[in] tag Tag identifying this request. |
| void SendInitialMetadata(void* tag) override { |
| GPR_CODEGEN_ASSERT(!ctx_->sent_initial_metadata_); |
| |
| meta_buf_.set_output_tag(tag); |
| meta_buf_.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| meta_buf_.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| call_.PerformOps(&meta_buf_); |
| } |
| |
| /// Indicate that the stream is to be finished and request notification |
| /// when the server has sent the appropriate signals to the client to |
| /// end the call. Should not be used concurrently with other operations. |
| /// |
| /// \param[in] tag Tag identifying this request. |
| /// \param[in] status To be sent to the client as the result of the call. |
| /// \param[in] msg Message to be sent to the client. |
| /// |
| /// Side effect: |
| /// - also sends initial metadata if not already sent (using the |
| /// \a ServerContext associated with this call). |
| /// |
| /// Note: if \a status has a non-OK code, then \a msg will not be sent, |
| /// and the client will receive only the status with possible trailing |
| /// metadata. |
| void Finish(const W& msg, const Status& status, void* tag) { |
| finish_buf_.set_output_tag(tag); |
| if (!ctx_->sent_initial_metadata_) { |
| finish_buf_.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| finish_buf_.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| } |
| // The response is dropped if the status is not OK. |
| if (status.ok()) { |
| finish_buf_.ServerSendStatus(ctx_->trailing_metadata_, |
| finish_buf_.SendMessage(msg)); |
| } else { |
| finish_buf_.ServerSendStatus(ctx_->trailing_metadata_, status); |
| } |
| call_.PerformOps(&finish_buf_); |
| } |
| |
| /// Indicate that the stream is to be finished with a non-OK status, |
| /// and request notification for when the server has finished sending the |
| /// appropriate signals to the client to end the call. |
| /// Should not be used concurrently with other operations. |
| /// |
| /// \param[in] tag Tag identifying this request. |
| /// \param[in] status To be sent to the client as the result of the call. |
| /// - Note: \a status must have a non-OK code. |
| /// |
| /// Side effect: |
| /// - also sends initial metadata if not already sent (using the |
| /// \a ServerContext associated with this call). |
| void FinishWithError(const Status& status, void* tag) { |
| GPR_CODEGEN_ASSERT(!status.ok()); |
| finish_buf_.set_output_tag(tag); |
| if (!ctx_->sent_initial_metadata_) { |
| finish_buf_.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| finish_buf_.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| } |
| finish_buf_.ServerSendStatus(ctx_->trailing_metadata_, status); |
| call_.PerformOps(&finish_buf_); |
| } |
| |
| private: |
| void BindCall(Call* call) override { call_ = *call; } |
| |
| Call call_; |
| ServerContext* ctx_; |
| CallOpSet<CallOpSendInitialMetadata> meta_buf_; |
| CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage, |
| CallOpServerSendStatus> |
| finish_buf_; |
| }; |
| |
| } // namespace grpc |
| |
| namespace std { |
| template <class R> |
| class default_delete<grpc::ClientAsyncResponseReader<R>> { |
| public: |
| void operator()(void* p) {} |
| }; |
| } |
| |
| #endif // GRPCXX_IMPL_CODEGEN_ASYNC_UNARY_CALL_H |