call_traits.hpp

#pragma once
 
#include <userver/ugrpc/server/rpc.hpp>
 
USERVER_NAMESPACE_BEGIN
 
namespace ugrpc::server::impl {
 
struct NoInitialRequest final {};
 
enum class CallCategory {
  kUnary,
  kInputStream,
  kOutputStream,
  kBidirectionalStream,
};
 
template <typename HandlerMethod>
struct CallTraits;
 
template <typename ServiceBaseType, typename RequestType, typename ResponseType>
struct CallTraits<void (ServiceBaseType::*)(UnaryCall<ResponseType>&,
                                            RequestType&&)>
    final {
  using ServiceBase = ServiceBaseType;
  using Request = RequestType;
  using Response = ResponseType;
  using RawCall = impl::RawResponseWriter<ResponseType>;
  using InitialRequest = Request;
  using Call = UnaryCall<Response>;
  using ServiceMethod = void (ServiceBase::*)(Call&, Request&&);
  static constexpr auto kCallCategory = CallCategory::kUnary;
};
 
template <typename ServiceBaseType, typename RequestType, typename ResponseType>
struct CallTraits<void (ServiceBaseType::*)(
    InputStream<RequestType, ResponseType>&)>
    final {
  using ServiceBase = ServiceBaseType;
  using Request = RequestType;
  using Response = ResponseType;
  using RawCall = impl::RawReader<Request, Response>;
  using InitialRequest = NoInitialRequest;
  using Call = InputStream<Request, Response>;
  using ServiceMethod = void (ServiceBase::*)(Call&);
  static constexpr auto kCallCategory = CallCategory::kInputStream;
};
 
template <typename ServiceBaseType, typename RequestType, typename ResponseType>
struct CallTraits<void (ServiceBaseType::*)(OutputStream<ResponseType>&,
                                            RequestType&&)>
    final {
  using ServiceBase = ServiceBaseType;
  using Request = RequestType;
  using Response = ResponseType;
  using RawCall = impl::RawWriter<Response>;
  using InitialRequest = Request;
  using Call = OutputStream<Response>;
  using ServiceMethod = void (ServiceBase::*)(Call&, Request&&);
  static constexpr auto kCallCategory = CallCategory::kOutputStream;
};
 
template <typename ServiceBaseType, typename RequestType, typename ResponseType>
struct CallTraits<void (ServiceBaseType::*)(
    BidirectionalStream<RequestType, ResponseType>&)>
    final {
  using ServiceBase = ServiceBaseType;
  using Request = RequestType;
  using Response = ResponseType;
  using RawCall = impl::RawReaderWriter<Request, Response>;
  using InitialRequest = NoInitialRequest;
  using Call = BidirectionalStream<Request, Response>;
  using ServiceMethod = void (ServiceBase::*)(Call&);
  static constexpr auto kCallCategory = CallCategory::kBidirectionalStream;
};
 
}  // namespace ugrpc::server::impl
 
USERVER_NAMESPACE_END