codec: Added basic interface and function class

Preparation work for RPC functionality.

1 files changed, 103 insertions, 0 deletions

diff --git a/c++/codec/rpc.h b/c++/codec/rpc.h
new file mode 100644
index 0000000..b1422a9
--- /dev/null
+++ b/c++/codec/rpc.h
@@ -0,0 +1,103 @@
+#pragma once
+
+#include <forstio/core/error.h>
+#include "schema.h"
+#include "data.h"
+
+namespace saw {
+template<typename SchemaFunc, typename Encode, typename Func>
+class function;
+
+template<typename Request, typename Response, typename Encode, typename Func>
+class function<schema::Function<Request, Response>, Encode, Func> {
+private:
+		Func func_;
+public:
+		function(Func func):
+				func_{std::move(func)}
+		{}
+
+		error_or<data<Response, Encode>> call(data<Request, Encode> req){
+				return func_(std::move(req));
+		}
+};
+
+template<typename T, typename Encode, typename... Funcs>
+class interface;
+
+template<typename... Requests, typename... Responses, string_literal... Names, typename Encode, typename... Funcs>
+class interface<schema::Interface<schema::Member<schema::Function<Requests, Responses>, Names>...>, Encode, Funcs...> {
+private:
+		std::tuple<function<schema::Function<Requests, Responses>, Encode, Funcs>...> funcs_;
+public:
+		interface(function<schema::Function<Requests, Responses>, Encode, Funcs>... funcs):
+				funcs_{std::move(funcs)...}
+		{}
+
+		/**
+		 * Get the function based on the string literal matching the position in the tuple
+		 */
+		template<string_literal Lit>
+		function<
+				schema::Function<
+						typename parameter_pack_type<
+								parameter_key_pack_index<
+										Lit, Names...
+								>::value
+						, Requests...>::type
+				,
+						typename parameter_pack_type<
+								parameter_key_pack_index<
+										Lit, Names...
+								>::value
+						, Responses...>::type
+				>
+		,
+				Encode
+		,
+				typename parameter_pack_type<
+						parameter_key_pack_index<
+								Lit, Names...
+						>::value
+				, Funcs...>::type
+		>& get(){
+				return std::get<parameter_key_pack_index<Lit, Names...>::value>(funcs_);
+		}
+
+		template<string_literal Lit>
+		error_or<data<
+				typename parameter_pack_type<
+						parameter_key_pack_index<
+								Lit, Names...
+						>::value
+				, Responses...>::type
+		, Encode>> call(
+						data<
+								typename parameter_pack_type<
+										parameter_key_pack_index<
+												Lit, Names...
+										>::value
+								, Requests...>::type
+						, Encode> req
+				){
+				return get<Lit>().call(std::move(req));
+		}
+
+};
+
+template<typename T, typename Encode>
+struct function_factory {
+		template<typename Func>
+		static function<T,Encode, Func> create(Func func){
+				return function<T,Encode,Func>{std::move(func)};
+		}
+};
+
+template<typename T, typename Encode>
+struct interface_factory {
+		template<typename... Func>
+		static interface<T,Encode, Func...> create(Func... func){
+				return interface<T,Encode, Func...>{std::move(func)...};
+		}
+};
+}