grpc/include/grpc++/impl/client_unary_call.h

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#ifndef GRPCXX_IMPL_CLIENT_UNARY_CALL_H
#define GRPCXX_IMPL_CLIENT_UNARY_CALL_H

#include <grpc++/impl/call.h>
#include <grpc++/support/config.h>
#include <grpc++/support/status.h>

namespace grpc {

class Channel;
class ClientContext;
class CompletionQueue;
class RpcMethod;

// Wrapper that performs a blocking unary call
template <class InputMessage, class OutputMessage>
Status BlockingUnaryCall(Channel* channel, const RpcMethod& method,
                         ClientContext* context, const InputMessage& request,
                         OutputMessage* result) {
  CompletionQueue cq;
  Call call(channel->CreateCall(method, context, &cq));
  CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage,
            CallOpRecvInitialMetadata, CallOpRecvMessage<OutputMessage>,
            CallOpClientSendClose, CallOpClientRecvStatus> ops;
  Status status = ops.SendMessage(request);
  if (!status.ok()) {
    return status;
  }
  ops.SendInitialMetadata(context->send_initial_metadata_);
  ops.RecvInitialMetadata(context);
  ops.RecvMessage(result);
  ops.ClientSendClose();
  ops.ClientRecvStatus(context, &status);
  call.PerformOps(&ops);
  GPR_ASSERT((cq.Pluck(&ops) && ops.got_message) || !status.ok());
  return status;
}

}  // namespace grpc

#endif  // GRPCXX_IMPL_CLIENT_UNARY_CALL_H