From 6a9cdf5272a230bfe82b0d5a9bf59869743ac5d5 Mon Sep 17 00:00:00 2001
From: Alexander Zaitsev <zamazan4ik@tut.by>
Date: Fri, 1 May 2020 01:48:20 +0300
Subject: [PATCH] Add possibility to register void methods as a JSON-RPC
 message

---
 include/jsonrpccxx/typemapper.hpp | 17 +++++++++++++++++
 test/typemapper.cpp               | 12 ++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/include/jsonrpccxx/typemapper.hpp b/include/jsonrpccxx/typemapper.hpp
index 57ad248..9ea7e13 100644
--- a/include/jsonrpccxx/typemapper.hpp
+++ b/include/jsonrpccxx/typemapper.hpp
@@ -24,6 +24,7 @@ namespace jsonrpccxx {
   constexpr json::value_t GetType(type<T>) {
     return json::value_t::object;
   }
+  constexpr json::value_t GetType(type<void>) { return json::value_t::null; }
   constexpr json::value_t GetType(type<std::string>) { return json::value_t::string; }
   constexpr json::value_t GetType(type<bool>) { return json::value_t::boolean; }
   constexpr json::value_t GetType(type<float>) { return json::value_t::number_float; }
@@ -148,6 +149,22 @@ namespace jsonrpccxx {
   //
   // Mapping for classes
   //
+  template <typename T, typename ReturnType, typename... ParamTypes>
+  MethodHandle methodHandle(ReturnType (T::*method)(ParamTypes...), T &instance) {
+    std::function<ReturnType(ParamTypes...)> function = [&instance, method](ParamTypes &&... params) -> ReturnType {
+      return (instance.*method)(std::forward<ParamTypes>(params)...);
+    };
+    return methodHandle(function);
+  }
+
+  template <typename T, typename... ParamTypes>
+  NotificationHandle notificationHandle(void (T::*method)(ParamTypes...), T &instance) {
+    std::function<void(ParamTypes...)> function = [&instance, method](ParamTypes &&... params) -> void {
+      return (instance.*method)(std::forward<ParamTypes>(params)...);
+    };
+    return notificationHandle(function);
+  }
+
   template <typename T, typename ReturnType, typename... ParamTypes>
   MethodHandle GetHandle(ReturnType (T::*method)(ParamTypes...), T &instance) {
     std::function<ReturnType(ParamTypes...)> function = [&instance, method](ParamTypes &&... params) -> ReturnType {
diff --git a/test/typemapper.cpp b/test/typemapper.cpp
index 1bd65ab..4abbe7e 100644
--- a/test/typemapper.cpp
+++ b/test/typemapper.cpp
@@ -43,6 +43,18 @@ TEST_CASE("test class member binding", TEST_MODULE) {
   CHECK(notifyResult == "Hello world: someone");
 }
 
+TEST_CASE("test class member explicit binding", TEST_MODULE) {
+  SomeClass instance;
+  MethodHandle mh = methodHandle(&SomeClass::add, instance);
+  CHECK(mh(R"([3, 4])"_json) == 7);
+
+  notifyResult = "";
+  NotificationHandle mh2 = notificationHandle(&SomeClass::notify, instance);
+  CHECK(notifyResult.empty());
+  mh2(R"(["someone"])"_json);
+  CHECK(notifyResult == "Hello world: someone");
+}
+
 TEST_CASE("test incorrect params", TEST_MODULE) {
   SomeClass instance;
   MethodHandle mh = GetHandle(&SomeClass::add, instance);