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/*
*
* 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* 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
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
#ifndef GRPCXX_SUPPORT_ASYNC_STREAM_H
#define GRPCXX_SUPPORT_ASYNC_STREAM_H
#include <grpc/support/log.h>
#include <grpc++/channel.h>
#include <grpc++/client_context.h>
#include <grpc++/completion_queue.h>
#include <grpc++/impl/call.h>
#include <grpc++/impl/service_type.h>
#include <grpc++/server_context.h>
#include <grpc++/support/status.h>
namespace grpc {
/// Common interface for all client side asynchronous streaming.
class ClientAsyncStreamingInterface {
public:
virtual ~ClientAsyncStreamingInterface() {}
/// Request notification of the reading of the initial metadata. Completion
/// will be notified by \a tag on the associated completion queue.
///
/// \param[in] tag Tag identifying this request.
virtual void ReadInitialMetadata(void* tag) = 0;
/// Request notification completion.
///
/// \param[out] status To be updated with the operation status.
/// \param[in] tag Tag identifying this request.
virtual void Finish(Status* status, void* tag) = 0;
};
/// An interface that yields a sequence of messages of type \a R.
template <class R>
class AsyncReaderInterface {
public:
virtual ~AsyncReaderInterface() {}
/// Read a message of type \a R into \a msg. Completion will be notified by \a
/// tag on the associated completion queue.
///
/// \param[out] msg Where to eventually store the read message.
/// \param[in] tag The tag identifying the operation.
virtual void Read(R* msg, void* tag) = 0;
};
/// An interface that can be fed a sequence of messages of type \a W.
template <class W>
class AsyncWriterInterface {
public:
virtual ~AsyncWriterInterface() {}
/// Request the writing of \a msg with identifying tag \a tag.
///
/// \param[in] msg The message to be written.
/// \param[in] tag The tag identifying the operation.
virtual void Write(const W& msg, void* tag) = 0;
};
template <class R>
class ClientAsyncReaderInterface : public ClientAsyncStreamingInterface,
public AsyncReaderInterface<R> {};
template <class R>
class ClientAsyncReader GRPC_FINAL : public ClientAsyncReaderInterface<R> {
public:
/// Create a stream and write the first request out.
template <class W>
ClientAsyncReader(Channel* channel, CompletionQueue* cq,
const RpcMethod& method, ClientContext* context,
const W& request, void* tag)
: context_(context), call_(channel->CreateCall(method, context, cq)) {
init_ops_.set_output_tag(tag);
init_ops_.SendInitialMetadata(context->send_initial_metadata_);
/// TODO(ctiller): don't assert
GPR_ASSERT(init_ops_.SendMessage(request).ok());
init_ops_.ClientSendClose();
call_.PerformOps(&init_ops_);
}
void ReadInitialMetadata(void* tag) GRPC_OVERRIDE {
GPR_ASSERT(!context_->initial_metadata_received_);
meta_ops_.set_output_tag(tag);
meta_ops_.RecvInitialMetadata(context_);
call_.PerformOps(&meta_ops_);
}
void Read(R* msg, void* tag) GRPC_OVERRIDE {
read_ops_.set_output_tag(tag);
if (!context_->initial_metadata_received_) {
read_ops_.RecvInitialMetadata(context_);
}
read_ops_.RecvMessage(msg);
call_.PerformOps(&read_ops_);
}
void Finish(Status* status, void* tag) GRPC_OVERRIDE {
finish_ops_.set_output_tag(tag);
if (!context_->initial_metadata_received_) {
finish_ops_.RecvInitialMetadata(context_);
}
finish_ops_.ClientRecvStatus(context_, status);
call_.PerformOps(&finish_ops_);
}
private:
ClientContext* context_;
Call call_;
CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage, CallOpClientSendClose>
init_ops_;
CallOpSet<CallOpRecvInitialMetadata> meta_ops_;
CallOpSet<CallOpRecvInitialMetadata, CallOpRecvMessage<R>> read_ops_;
CallOpSet<CallOpRecvInitialMetadata, CallOpClientRecvStatus> finish_ops_;
};
/// Common interface for client side asynchronous writing.
template <class W>
class ClientAsyncWriterInterface : public ClientAsyncStreamingInterface,
public AsyncWriterInterface<W> {
public:
/// Signal the client is done with the writes.
///
/// \param[in] tag The tag identifying the operation.
virtual void WritesDone(void* tag) = 0;
};
template <class W>
class ClientAsyncWriter GRPC_FINAL : public ClientAsyncWriterInterface<W> {
public:
template <class R>
ClientAsyncWriter(Channel* channel, CompletionQueue* cq,
const RpcMethod& method, ClientContext* context,
R* response, void* tag)
: context_(context), call_(channel->CreateCall(method, context, cq)) {
finish_ops_.RecvMessage(response);
init_ops_.set_output_tag(tag);
init_ops_.SendInitialMetadata(context->send_initial_metadata_);
call_.PerformOps(&init_ops_);
}
void ReadInitialMetadata(void* tag) GRPC_OVERRIDE {
GPR_ASSERT(!context_->initial_metadata_received_);
meta_ops_.set_output_tag(tag);
meta_ops_.RecvInitialMetadata(context_);
call_.PerformOps(&meta_ops_);
}
void Write(const W& msg, void* tag) GRPC_OVERRIDE {
write_ops_.set_output_tag(tag);
/// TODO(ctiller): don't assert
GPR_ASSERT(write_ops_.SendMessage(msg).ok());
call_.PerformOps(&write_ops_);
}
void WritesDone(void* tag) GRPC_OVERRIDE {
writes_done_ops_.set_output_tag(tag);
writes_done_ops_.ClientSendClose();
call_.PerformOps(&writes_done_ops_);
}
void Finish(Status* status, void* tag) GRPC_OVERRIDE {
finish_ops_.set_output_tag(tag);
if (!context_->initial_metadata_received_) {
finish_ops_.RecvInitialMetadata(context_);
}
finish_ops_.ClientRecvStatus(context_, status);
call_.PerformOps(&finish_ops_);
}
private:
ClientContext* context_;
Call call_;
CallOpSet<CallOpSendInitialMetadata> init_ops_;
CallOpSet<CallOpRecvInitialMetadata> meta_ops_;
CallOpSet<CallOpSendMessage> write_ops_;
CallOpSet<CallOpClientSendClose> writes_done_ops_;
CallOpSet<CallOpRecvInitialMetadata, CallOpGenericRecvMessage,
CallOpClientRecvStatus> finish_ops_;
};
/// Client-side interface for asynchronous bi-directional streaming.
template <class W, class R>
class ClientAsyncReaderWriterInterface : public ClientAsyncStreamingInterface,
public AsyncWriterInterface<W>,
public AsyncReaderInterface<R> {
public:
/// Signal the client is done with the writes.
///
/// \param[in] tag The tag identifying the operation.
virtual void WritesDone(void* tag) = 0;
};
template <class W, class R>
class ClientAsyncReaderWriter GRPC_FINAL
: public ClientAsyncReaderWriterInterface<W, R> {
public:
ClientAsyncReaderWriter(Channel* channel, CompletionQueue* cq,
const RpcMethod& method, ClientContext* context,
void* tag)
: context_(context), call_(channel->CreateCall(method, context, cq)) {
init_ops_.set_output_tag(tag);
init_ops_.SendInitialMetadata(context->send_initial_metadata_);
call_.PerformOps(&init_ops_);
}
void ReadInitialMetadata(void* tag) GRPC_OVERRIDE {
GPR_ASSERT(!context_->initial_metadata_received_);
meta_ops_.set_output_tag(tag);
meta_ops_.RecvInitialMetadata(context_);
call_.PerformOps(&meta_ops_);
}
void Read(R* msg, void* tag) GRPC_OVERRIDE {
read_ops_.set_output_tag(tag);
if (!context_->initial_metadata_received_) {
read_ops_.RecvInitialMetadata(context_);
}
read_ops_.RecvMessage(msg);
call_.PerformOps(&read_ops_);
}
void Write(const W& msg, void* tag) GRPC_OVERRIDE {
write_ops_.set_output_tag(tag);
/// TODO(ctiller): don't assert
GPR_ASSERT(write_ops_.SendMessage(msg).ok());
call_.PerformOps(&write_ops_);
}
void WritesDone(void* tag) GRPC_OVERRIDE {
writes_done_ops_.set_output_tag(tag);
writes_done_ops_.ClientSendClose();
call_.PerformOps(&writes_done_ops_);
}
void Finish(Status* status, void* tag) GRPC_OVERRIDE {
finish_ops_.set_output_tag(tag);
if (!context_->initial_metadata_received_) {
finish_ops_.RecvInitialMetadata(context_);
}
finish_ops_.ClientRecvStatus(context_, status);
call_.PerformOps(&finish_ops_);
}
private:
ClientContext* context_;
Call call_;
CallOpSet<CallOpSendInitialMetadata> init_ops_;
CallOpSet<CallOpRecvInitialMetadata> meta_ops_;
CallOpSet<CallOpRecvInitialMetadata, CallOpRecvMessage<R>> read_ops_;
CallOpSet<CallOpSendMessage> write_ops_;
CallOpSet<CallOpClientSendClose> writes_done_ops_;
CallOpSet<CallOpRecvInitialMetadata, CallOpClientRecvStatus> finish_ops_;
};
template <class W, class R>
class ServerAsyncReader GRPC_FINAL : public ServerAsyncStreamingInterface,
public AsyncReaderInterface<R> {
public:
explicit ServerAsyncReader(ServerContext* ctx)
: call_(nullptr, nullptr, nullptr), ctx_(ctx) {}
void SendInitialMetadata(void* tag) GRPC_OVERRIDE {
GPR_ASSERT(!ctx_->sent_initial_metadata_);
meta_ops_.set_output_tag(tag);
meta_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
call_.PerformOps(&meta_ops_);
}
void Read(R* msg, void* tag) GRPC_OVERRIDE {
read_ops_.set_output_tag(tag);
read_ops_.RecvMessage(msg);
call_.PerformOps(&read_ops_);
}
void Finish(const W& msg, const Status& status, void* tag) {
finish_ops_.set_output_tag(tag);
if (!ctx_->sent_initial_metadata_) {
finish_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
}
// The response is dropped if the status is not OK.
if (status.ok()) {
finish_ops_.ServerSendStatus(ctx_->trailing_metadata_,
finish_ops_.SendMessage(msg));
} else {
finish_ops_.ServerSendStatus(ctx_->trailing_metadata_, status);
}
call_.PerformOps(&finish_ops_);
}
void FinishWithError(const Status& status, void* tag) {
GPR_ASSERT(!status.ok());
finish_ops_.set_output_tag(tag);
if (!ctx_->sent_initial_metadata_) {
finish_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
}
finish_ops_.ServerSendStatus(ctx_->trailing_metadata_, status);
call_.PerformOps(&finish_ops_);
}
private:
void BindCall(Call* call) GRPC_OVERRIDE { call_ = *call; }
Call call_;
ServerContext* ctx_;
CallOpSet<CallOpSendInitialMetadata> meta_ops_;
CallOpSet<CallOpRecvMessage<R>> read_ops_;
CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
CallOpServerSendStatus> finish_ops_;
};
template <class W>
class ServerAsyncWriter GRPC_FINAL : public ServerAsyncStreamingInterface,
public AsyncWriterInterface<W> {
public:
explicit ServerAsyncWriter(ServerContext* ctx)
: call_(nullptr, nullptr, nullptr), ctx_(ctx) {}
void SendInitialMetadata(void* tag) GRPC_OVERRIDE {
GPR_ASSERT(!ctx_->sent_initial_metadata_);
meta_ops_.set_output_tag(tag);
meta_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
call_.PerformOps(&meta_ops_);
}
void Write(const W& msg, void* tag) GRPC_OVERRIDE {
write_ops_.set_output_tag(tag);
if (!ctx_->sent_initial_metadata_) {
write_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
}
/// TODO(ctiller): don't assert
GPR_ASSERT(write_ops_.SendMessage(msg).ok());
call_.PerformOps(&write_ops_);
}
void Finish(const Status& status, void* tag) {
finish_ops_.set_output_tag(tag);
if (!ctx_->sent_initial_metadata_) {
finish_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
}
finish_ops_.ServerSendStatus(ctx_->trailing_metadata_, status);
call_.PerformOps(&finish_ops_);
}
private:
void BindCall(Call* call) GRPC_OVERRIDE { call_ = *call; }
Call call_;
ServerContext* ctx_;
CallOpSet<CallOpSendInitialMetadata> meta_ops_;
CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage> write_ops_;
CallOpSet<CallOpSendInitialMetadata, CallOpServerSendStatus> finish_ops_;
};
/// Server-side interface for asynchronous bi-directional streaming.
template <class W, class R>
class ServerAsyncReaderWriter GRPC_FINAL : public ServerAsyncStreamingInterface,
public AsyncWriterInterface<W>,
public AsyncReaderInterface<R> {
public:
explicit ServerAsyncReaderWriter(ServerContext* ctx)
: call_(nullptr, nullptr, nullptr), ctx_(ctx) {}
void SendInitialMetadata(void* tag) GRPC_OVERRIDE {
GPR_ASSERT(!ctx_->sent_initial_metadata_);
meta_ops_.set_output_tag(tag);
meta_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
call_.PerformOps(&meta_ops_);
}
void Read(R* msg, void* tag) GRPC_OVERRIDE {
read_ops_.set_output_tag(tag);
read_ops_.RecvMessage(msg);
call_.PerformOps(&read_ops_);
}
void Write(const W& msg, void* tag) GRPC_OVERRIDE {
write_ops_.set_output_tag(tag);
if (!ctx_->sent_initial_metadata_) {
write_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
}
// TODO(ctiller): don't assert
GPR_ASSERT(write_ops_.SendMessage(msg).ok());
call_.PerformOps(&write_ops_);
}
void Finish(const Status& status, void* tag) {
finish_ops_.set_output_tag(tag);
if (!ctx_->sent_initial_metadata_) {
finish_ops_.SendInitialMetadata(ctx_->initial_metadata_);
ctx_->sent_initial_metadata_ = true;
}
finish_ops_.ServerSendStatus(ctx_->trailing_metadata_, status);
call_.PerformOps(&finish_ops_);
}
private:
friend class ::grpc::Server;
void BindCall(Call* call) GRPC_OVERRIDE { call_ = *call; }
Call call_;
ServerContext* ctx_;
CallOpSet<CallOpSendInitialMetadata> meta_ops_;
CallOpSet<CallOpRecvMessage<R>> read_ops_;
CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage> write_ops_;
CallOpSet<CallOpSendInitialMetadata, CallOpServerSendStatus> finish_ops_;
};
} // namespace grpc
#endif // GRPCXX_SUPPORT_ASYNC_STREAM_H