| /* |
| * |
| * Copyright 2015, Google Inc. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
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| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
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| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| |
| #ifndef GRPCXX_IMPL_CODEGEN_SYNC_STREAM_H |
| #define GRPCXX_IMPL_CODEGEN_SYNC_STREAM_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/completion_queue.h> |
| #include <grpc++/impl/codegen/core_codegen_interface.h> |
| #include <grpc++/impl/codegen/server_context.h> |
| #include <grpc++/impl/codegen/service_type.h> |
| #include <grpc++/impl/codegen/status.h> |
| |
| namespace grpc { |
| |
| /// Common interface for all synchronous client side streaming. |
| class ClientStreamingInterface { |
| public: |
| virtual ~ClientStreamingInterface() {} |
| |
| /// Wait until the stream finishes, and return the final status. When the |
| /// client side declares it has no more message to send, either implicitly or |
| /// by calling \a WritesDone(), it needs to make sure there is no more message |
| /// to be received from the server, either implicitly or by getting a false |
| /// from a \a Read(). |
| /// |
| /// This function will return either: |
| /// - when all incoming messages have been read and the server has returned |
| /// status. |
| /// - OR when the server has returned a non-OK status. |
| virtual Status Finish() = 0; |
| }; |
| |
| /// Common interface for all synchronous server side streaming. |
| class ServerStreamingInterface { |
| public: |
| virtual ~ServerStreamingInterface() {} |
| |
| /// Blocking send initial metadata to client. |
| virtual void SendInitialMetadata() = 0; |
| }; |
| |
| /// An interface that yields a sequence of messages of type \a R. |
| template <class R> |
| class ReaderInterface { |
| public: |
| virtual ~ReaderInterface() {} |
| |
| /// Upper bound on the next message size available for reading on this stream |
| virtual bool NextMessageSize(uint32_t* sz) = 0; |
| |
| /// Blocking read a message and parse to \a msg. Returns \a true on success. |
| /// This is thread-safe with respect to \a Write or \WritesDone methods on |
| /// the same stream. It should not be called concurrently with another \a |
| /// Read on the same stream as the order of delivery will not be defined. |
| /// |
| /// \param[out] msg The read message. |
| /// |
| /// \return \a false when there will be no more incoming messages, either |
| /// because the other side has called \a WritesDone() or the stream has failed |
| /// (or been cancelled). |
| virtual bool Read(R* msg) = 0; |
| }; |
| |
| /// An interface that can be fed a sequence of messages of type \a W. |
| template <class W> |
| class WriterInterface { |
| public: |
| virtual ~WriterInterface() {} |
| |
| /// Blocking write \a msg to the stream with options. |
| /// This is thread-safe with respect to \a Read |
| /// |
| /// \param msg The message to be written to the stream. |
| /// \param options Options affecting the write operation. |
| /// |
| /// \return \a true on success, \a false when the stream has been closed. |
| virtual bool Write(const W& msg, const WriteOptions& options) = 0; |
| |
| /// Blocking write \a msg to the stream with default options. |
| /// This is thread-safe with respect to \a Read |
| /// |
| /// \param msg The message to be written to the stream. |
| /// |
| /// \return \a true on success, \a false when the stream has been closed. |
| inline bool Write(const W& msg) { return Write(msg, WriteOptions()); } |
| }; |
| |
| /// Client-side interface for streaming reads of message of type \a R. |
| template <class R> |
| class ClientReaderInterface : public ClientStreamingInterface, |
| public ReaderInterface<R> { |
| public: |
| /// Blocking wait for initial metadata from server. The received metadata |
| /// can only be accessed after this call returns. Should only be called before |
| /// the first read. Calling this method is optional, and if it is not called |
| /// the metadata will be available in ClientContext after the first read. |
| virtual void WaitForInitialMetadata() = 0; |
| }; |
| |
| template <class R> |
| class ClientReader GRPC_FINAL : public ClientReaderInterface<R> { |
| public: |
| /// Blocking create a stream and write the first request out. |
| template <class W> |
| ClientReader(ChannelInterface* channel, const RpcMethod& method, |
| ClientContext* context, const W& request) |
| : context_(context), call_(channel->CreateCall(method, context, &cq_)) { |
| CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage, |
| CallOpClientSendClose> |
| ops; |
| ops.SendInitialMetadata(context->send_initial_metadata_, |
| context->initial_metadata_flags()); |
| // TODO(ctiller): don't assert |
| GPR_CODEGEN_ASSERT(ops.SendMessage(request).ok()); |
| ops.ClientSendClose(); |
| call_.PerformOps(&ops); |
| cq_.Pluck(&ops); |
| } |
| |
| void WaitForInitialMetadata() GRPC_OVERRIDE { |
| GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_); |
| |
| CallOpSet<CallOpRecvInitialMetadata> ops; |
| ops.RecvInitialMetadata(context_); |
| call_.PerformOps(&ops); |
| cq_.Pluck(&ops); /// status ignored |
| } |
| |
| bool NextMessageSize(uint32_t* sz) GRPC_OVERRIDE { |
| *sz = call_.max_receive_message_size(); |
| return true; |
| } |
| |
| bool Read(R* msg) GRPC_OVERRIDE { |
| CallOpSet<CallOpRecvInitialMetadata, CallOpRecvMessage<R>> ops; |
| if (!context_->initial_metadata_received_) { |
| ops.RecvInitialMetadata(context_); |
| } |
| ops.RecvMessage(msg); |
| call_.PerformOps(&ops); |
| return cq_.Pluck(&ops) && ops.got_message; |
| } |
| |
| Status Finish() GRPC_OVERRIDE { |
| CallOpSet<CallOpClientRecvStatus> ops; |
| Status status; |
| ops.ClientRecvStatus(context_, &status); |
| call_.PerformOps(&ops); |
| GPR_CODEGEN_ASSERT(cq_.Pluck(&ops)); |
| return status; |
| } |
| |
| private: |
| ClientContext* context_; |
| CompletionQueue cq_; |
| Call call_; |
| }; |
| |
| /// Client-side interface for streaming writes of message of type \a W. |
| template <class W> |
| class ClientWriterInterface : public ClientStreamingInterface, |
| public WriterInterface<W> { |
| public: |
| /// Half close writing from the client. |
| /// Block until currently-pending writes are completed. |
| /// Thread safe with respect to \a Read operations only |
| /// |
| /// \return Whether the writes were successful. |
| virtual bool WritesDone() = 0; |
| }; |
| |
| template <class W> |
| class ClientWriter : public ClientWriterInterface<W> { |
| public: |
| /// Blocking create a stream. |
| template <class R> |
| ClientWriter(ChannelInterface* channel, const RpcMethod& method, |
| ClientContext* context, R* response) |
| : context_(context), call_(channel->CreateCall(method, context, &cq_)) { |
| finish_ops_.RecvMessage(response); |
| finish_ops_.AllowNoMessage(); |
| |
| CallOpSet<CallOpSendInitialMetadata> ops; |
| ops.SendInitialMetadata(context->send_initial_metadata_, |
| context->initial_metadata_flags()); |
| call_.PerformOps(&ops); |
| cq_.Pluck(&ops); |
| } |
| |
| void WaitForInitialMetadata() { |
| GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_); |
| |
| CallOpSet<CallOpRecvInitialMetadata> ops; |
| ops.RecvInitialMetadata(context_); |
| call_.PerformOps(&ops); |
| cq_.Pluck(&ops); // status ignored |
| } |
| |
| using WriterInterface<W>::Write; |
| bool Write(const W& msg, const WriteOptions& options) GRPC_OVERRIDE { |
| CallOpSet<CallOpSendMessage> ops; |
| if (!ops.SendMessage(msg, options).ok()) { |
| return false; |
| } |
| call_.PerformOps(&ops); |
| return cq_.Pluck(&ops); |
| } |
| |
| bool WritesDone() GRPC_OVERRIDE { |
| CallOpSet<CallOpClientSendClose> ops; |
| ops.ClientSendClose(); |
| call_.PerformOps(&ops); |
| return cq_.Pluck(&ops); |
| } |
| |
| /// Read the final response and wait for the final status. |
| Status Finish() GRPC_OVERRIDE { |
| Status status; |
| if (!context_->initial_metadata_received_) { |
| finish_ops_.RecvInitialMetadata(context_); |
| } |
| finish_ops_.ClientRecvStatus(context_, &status); |
| call_.PerformOps(&finish_ops_); |
| GPR_CODEGEN_ASSERT(cq_.Pluck(&finish_ops_)); |
| return status; |
| } |
| |
| private: |
| ClientContext* context_; |
| CallOpSet<CallOpRecvInitialMetadata, CallOpGenericRecvMessage, |
| CallOpClientRecvStatus> |
| finish_ops_; |
| CompletionQueue cq_; |
| Call call_; |
| }; |
| |
| /// Client-side interface for bi-directional streaming. |
| template <class W, class R> |
| class ClientReaderWriterInterface : public ClientStreamingInterface, |
| public WriterInterface<W>, |
| public ReaderInterface<R> { |
| public: |
| /// Blocking wait for initial metadata from server. The received metadata |
| /// can only be accessed after this call returns. Should only be called before |
| /// the first read. Calling this method is optional, and if it is not called |
| /// the metadata will be available in ClientContext after the first read. |
| virtual void WaitForInitialMetadata() = 0; |
| |
| /// Block until currently-pending writes are completed. |
| /// Thread-safe with respect to \a Read |
| /// |
| /// \return Whether the writes were successful. |
| virtual bool WritesDone() = 0; |
| }; |
| |
| template <class W, class R> |
| class ClientReaderWriter GRPC_FINAL : public ClientReaderWriterInterface<W, R> { |
| public: |
| /// Blocking create a stream. |
| ClientReaderWriter(ChannelInterface* channel, const RpcMethod& method, |
| ClientContext* context) |
| : context_(context), call_(channel->CreateCall(method, context, &cq_)) { |
| CallOpSet<CallOpSendInitialMetadata> ops; |
| ops.SendInitialMetadata(context->send_initial_metadata_, |
| context->initial_metadata_flags()); |
| call_.PerformOps(&ops); |
| cq_.Pluck(&ops); |
| } |
| |
| void WaitForInitialMetadata() GRPC_OVERRIDE { |
| GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_); |
| |
| CallOpSet<CallOpRecvInitialMetadata> ops; |
| ops.RecvInitialMetadata(context_); |
| call_.PerformOps(&ops); |
| cq_.Pluck(&ops); // status ignored |
| } |
| |
| bool NextMessageSize(uint32_t* sz) GRPC_OVERRIDE { |
| *sz = call_.max_receive_message_size(); |
| return true; |
| } |
| |
| bool Read(R* msg) GRPC_OVERRIDE { |
| CallOpSet<CallOpRecvInitialMetadata, CallOpRecvMessage<R>> ops; |
| if (!context_->initial_metadata_received_) { |
| ops.RecvInitialMetadata(context_); |
| } |
| ops.RecvMessage(msg); |
| call_.PerformOps(&ops); |
| return cq_.Pluck(&ops) && ops.got_message; |
| } |
| |
| using WriterInterface<W>::Write; |
| bool Write(const W& msg, const WriteOptions& options) GRPC_OVERRIDE { |
| CallOpSet<CallOpSendMessage> ops; |
| if (!ops.SendMessage(msg, options).ok()) return false; |
| call_.PerformOps(&ops); |
| return cq_.Pluck(&ops); |
| } |
| |
| bool WritesDone() GRPC_OVERRIDE { |
| CallOpSet<CallOpClientSendClose> ops; |
| ops.ClientSendClose(); |
| call_.PerformOps(&ops); |
| return cq_.Pluck(&ops); |
| } |
| |
| Status Finish() GRPC_OVERRIDE { |
| CallOpSet<CallOpRecvInitialMetadata, CallOpClientRecvStatus> ops; |
| if (!context_->initial_metadata_received_) { |
| ops.RecvInitialMetadata(context_); |
| } |
| Status status; |
| ops.ClientRecvStatus(context_, &status); |
| call_.PerformOps(&ops); |
| GPR_CODEGEN_ASSERT(cq_.Pluck(&ops)); |
| return status; |
| } |
| |
| private: |
| ClientContext* context_; |
| CompletionQueue cq_; |
| Call call_; |
| }; |
| |
| /// Server-side interface for streaming reads of message of type \a R. |
| template <class R> |
| class ServerReaderInterface : public ServerStreamingInterface, |
| public ReaderInterface<R> {}; |
| |
| template <class R> |
| class ServerReader GRPC_FINAL : public ServerReaderInterface<R> { |
| public: |
| ServerReader(Call* call, ServerContext* ctx) : call_(call), ctx_(ctx) {} |
| |
| void SendInitialMetadata() GRPC_OVERRIDE { |
| GPR_CODEGEN_ASSERT(!ctx_->sent_initial_metadata_); |
| |
| CallOpSet<CallOpSendInitialMetadata> ops; |
| ops.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| ops.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| call_->PerformOps(&ops); |
| call_->cq()->Pluck(&ops); |
| } |
| |
| bool NextMessageSize(uint32_t* sz) GRPC_OVERRIDE { |
| *sz = call_->max_receive_message_size(); |
| return true; |
| } |
| |
| bool Read(R* msg) GRPC_OVERRIDE { |
| CallOpSet<CallOpRecvMessage<R>> ops; |
| ops.RecvMessage(msg); |
| call_->PerformOps(&ops); |
| return call_->cq()->Pluck(&ops) && ops.got_message; |
| } |
| |
| private: |
| Call* const call_; |
| ServerContext* const ctx_; |
| }; |
| |
| /// Server-side interface for streaming writes of message of type \a W. |
| template <class W> |
| class ServerWriterInterface : public ServerStreamingInterface, |
| public WriterInterface<W> {}; |
| |
| template <class W> |
| class ServerWriter GRPC_FINAL : public ServerWriterInterface<W> { |
| public: |
| ServerWriter(Call* call, ServerContext* ctx) : call_(call), ctx_(ctx) {} |
| |
| void SendInitialMetadata() GRPC_OVERRIDE { |
| GPR_CODEGEN_ASSERT(!ctx_->sent_initial_metadata_); |
| |
| CallOpSet<CallOpSendInitialMetadata> ops; |
| ops.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| ops.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| call_->PerformOps(&ops); |
| call_->cq()->Pluck(&ops); |
| } |
| |
| using WriterInterface<W>::Write; |
| bool Write(const W& msg, const WriteOptions& options) GRPC_OVERRIDE { |
| CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage> ops; |
| if (!ops.SendMessage(msg, options).ok()) { |
| return false; |
| } |
| if (!ctx_->sent_initial_metadata_) { |
| ops.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| ops.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| } |
| call_->PerformOps(&ops); |
| return call_->cq()->Pluck(&ops); |
| } |
| |
| private: |
| Call* const call_; |
| ServerContext* const ctx_; |
| }; |
| |
| /// Server-side interface for bi-directional streaming. |
| template <class W, class R> |
| class ServerReaderWriterInterface : public ServerStreamingInterface, |
| public WriterInterface<W>, |
| public ReaderInterface<R> {}; |
| |
| // Actual implementation of bi-directional streaming |
| namespace internal { |
| template <class W, class R> |
| class ServerReaderWriterBody GRPC_FINAL { |
| public: |
| ServerReaderWriterBody(Call* call, ServerContext* ctx) |
| : call_(call), ctx_(ctx) {} |
| |
| void SendInitialMetadata() { |
| GPR_CODEGEN_ASSERT(!ctx_->sent_initial_metadata_); |
| |
| CallOpSet<CallOpSendInitialMetadata> ops; |
| ops.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| ops.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| call_->PerformOps(&ops); |
| call_->cq()->Pluck(&ops); |
| } |
| |
| bool NextMessageSize(uint32_t* sz) { |
| *sz = call_->max_receive_message_size(); |
| return true; |
| } |
| |
| bool Read(R* msg) { |
| CallOpSet<CallOpRecvMessage<R>> ops; |
| ops.RecvMessage(msg); |
| call_->PerformOps(&ops); |
| return call_->cq()->Pluck(&ops) && ops.got_message; |
| } |
| |
| bool Write(const W& msg, const WriteOptions& options) { |
| CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage> ops; |
| if (!ops.SendMessage(msg, options).ok()) { |
| return false; |
| } |
| if (!ctx_->sent_initial_metadata_) { |
| ops.SendInitialMetadata(ctx_->initial_metadata_, |
| ctx_->initial_metadata_flags()); |
| if (ctx_->compression_level_set()) { |
| ops.set_compression_level(ctx_->compression_level()); |
| } |
| ctx_->sent_initial_metadata_ = true; |
| } |
| call_->PerformOps(&ops); |
| return call_->cq()->Pluck(&ops); |
| } |
| |
| private: |
| Call* const call_; |
| ServerContext* const ctx_; |
| }; |
| } |
| |
| // class to represent the user API for a bidirectional streaming call |
| template <class W, class R> |
| class ServerReaderWriter GRPC_FINAL : public ServerReaderWriterInterface<W, R> { |
| public: |
| ServerReaderWriter(Call* call, ServerContext* ctx) : body_(call, ctx) {} |
| |
| void SendInitialMetadata() GRPC_OVERRIDE { body_.SendInitialMetadata(); } |
| |
| bool NextMessageSize(uint32_t* sz) GRPC_OVERRIDE { |
| return body_.NextMessageSize(sz); |
| } |
| |
| bool Read(R* msg) GRPC_OVERRIDE { return body_.Read(msg); } |
| |
| using WriterInterface<W>::Write; |
| bool Write(const W& msg, const WriteOptions& options) GRPC_OVERRIDE { |
| return body_.Write(msg, options); |
| } |
| |
| private: |
| internal::ServerReaderWriterBody<W, R> body_; |
| }; |
| |
| /// A class to represent a flow-controlled unary call. This is something |
| /// of a hybrid between conventional unary and streaming. This is invoked |
| /// through a unary call on the client side, but the server responds to it |
| /// as though it were a single-ping-pong streaming call. The server can use |
| /// the \a NextMessageSize method to determine an upper-bound on the size of |
| /// the message. |
| /// A key difference relative to streaming: ServerUnaryStreamer |
| /// must have exactly 1 Read and exactly 1 Write, in that order, to function |
| /// correctly. Otherwise, the RPC is in error. |
| template <class RequestType, class ResponseType> |
| class ServerUnaryStreamer GRPC_FINAL |
| : public ServerReaderWriterInterface<ResponseType, RequestType> { |
| public: |
| ServerUnaryStreamer(Call* call, ServerContext* ctx) |
| : body_(call, ctx), read_done_(false), write_done_(false) {} |
| |
| void SendInitialMetadata() GRPC_OVERRIDE { body_.SendInitialMetadata(); } |
| |
| bool NextMessageSize(uint32_t* sz) GRPC_OVERRIDE { |
| return body_.NextMessageSize(sz); |
| } |
| |
| bool Read(RequestType* request) GRPC_OVERRIDE { |
| if (read_done_) { |
| return false; |
| } |
| read_done_ = true; |
| return body_.Read(request); |
| } |
| |
| using WriterInterface<ResponseType>::Write; |
| bool Write(const ResponseType& response, |
| const WriteOptions& options) GRPC_OVERRIDE { |
| if (write_done_ || !read_done_) { |
| return false; |
| } |
| write_done_ = true; |
| return body_.Write(response, options); |
| } |
| |
| private: |
| internal::ServerReaderWriterBody<ResponseType, RequestType> body_; |
| bool read_done_; |
| bool write_done_; |
| }; |
| |
| } // namespace grpc |
| |
| #endif // GRPCXX_IMPL_CODEGEN_SYNC_STREAM_H |