[Net] Modularize multiplayer, expose MultiplayerAPI to extensions.

- RPC configurations are now dictionaries.
- Script.get_rpc_methods renamed to Script.get_rpc_config.
- Node.rpc[_id] and Callable.rpc now return an Error.
- Refactor MultiplayerAPI to allow extension.
- New MultiplayerAPI.rpc method with Array argument (for scripts).
- Move the default MultiplayerAPI implementation to a module.

1 files changed, 17 insertions, 22 deletions

diff --git a/modules/mono/csharp_script.cpp b/modules/mono/csharp_script.cpp
index 1e4d82ca30..06793d25e0 100644
--- a/modules/mono/csharp_script.cpp
+++ b/modules/mono/csharp_script.cpp
@@ -2141,8 +2141,8 @@ bool CSharpInstance::refcount_decremented() {
 	return ref_dying;
 }
 
-const Vector<Multiplayer::RPCConfig> CSharpInstance::get_rpc_methods() const {
-	return script->get_rpc_methods();
+const Variant CSharpInstance::get_rpc_config() const {
+	return script->get_rpc_config();
 }
 
 void CSharpInstance::notification(int p_notification) {
@@ -3060,7 +3060,7 @@ void CSharpScript::update_script_class_info(Ref<CSharpScript> p_script) {
 
 	p_script->script_class->fetch_methods_with_godot_api_checks(p_script->native);
 
-	p_script->rpc_functions.clear();
+	p_script->rpc_config.clear();
 
 	GDMonoClass *top = p_script->script_class;
 	while (top && top != p_script->native) {
@@ -3072,12 +3072,9 @@ void CSharpScript::update_script_class_info(Ref<CSharpScript> p_script) {
 			Vector<GDMonoMethod *> methods = top->get_all_methods();
 			for (int i = 0; i < methods.size(); i++) {
 				if (!methods[i]->is_static()) {
-					Multiplayer::RPCConfig rpc_config = p_script->_member_get_rpc_config(methods[i]);
-					if (rpc_config.rpc_mode != Multiplayer::RPC_MODE_DISABLED) {
-						// RPC annotations can only be used once per method
-						if (p_script->rpc_functions.find(rpc_config) == -1) {
-							p_script->rpc_functions.push_back(rpc_config);
-						}
+					const Variant rpc_config = p_script->_member_get_rpc_config(methods[i]);
+					if (rpc_config.get_type() != Variant::NIL) {
+						p_script->rpc_config[methods[i]->get_name()] = rpc_config;
 					}
 				}
 			}
@@ -3086,9 +3083,6 @@ void CSharpScript::update_script_class_info(Ref<CSharpScript> p_script) {
 		top = top->get_parent_class();
 	}
 
-	// Sort so we are 100% that they are always the same.
-	p_script->rpc_functions.sort_custom<Multiplayer::SortRPCConfig>();
-
 	p_script->load_script_signals(p_script->script_class, p_script->native);
 }
 
@@ -3511,23 +3505,24 @@ int CSharpScript::get_member_line(const StringName &p_member) const {
 	return -1;
 }
 
-Multiplayer::RPCConfig CSharpScript::_member_get_rpc_config(IMonoClassMember *p_member) const {
-	Multiplayer::RPCConfig rpc_config;
+Variant CSharpScript::_member_get_rpc_config(IMonoClassMember *p_member) const {
+	Variant out;
 
 	MonoObject *rpc_attribute = p_member->get_attribute(CACHED_CLASS(RPCAttribute));
 	if (rpc_attribute != nullptr) {
-		rpc_config.name = p_member->get_name();
-		rpc_config.rpc_mode = (Multiplayer::RPCMode)CACHED_PROPERTY(RPCAttribute, Mode)->get_int_value(rpc_attribute);
-		rpc_config.call_local = CACHED_PROPERTY(RPCAttribute, CallLocal)->get_bool_value(rpc_attribute);
-		rpc_config.transfer_mode = (Multiplayer::TransferMode)CACHED_PROPERTY(RPCAttribute, TransferMode)->get_int_value(rpc_attribute);
-		rpc_config.channel = CACHED_PROPERTY(RPCAttribute, TransferChannel)->get_int_value(rpc_attribute);
+		Dictionary rpc_config;
+		rpc_config["rpc_mode"] = CACHED_PROPERTY(RPCAttribute, Mode)->get_int_value(rpc_attribute);
+		rpc_config["call_local"] = CACHED_PROPERTY(RPCAttribute, CallLocal)->get_bool_value(rpc_attribute);
+		rpc_config["transfer_mode"] = CACHED_PROPERTY(RPCAttribute, TransferMode)->get_int_value(rpc_attribute);
+		rpc_config["channel"] = CACHED_PROPERTY(RPCAttribute, TransferChannel)->get_int_value(rpc_attribute);
+		out = rpc_config;
 	}
 
-	return rpc_config;
+	return out;
 }
 
-const Vector<Multiplayer::RPCConfig> CSharpScript::get_rpc_methods() const {
-	return rpc_functions;
+const Variant CSharpScript::get_rpc_config() const {
+	return rpc_config;
 }
 
 Error CSharpScript::load_source_code(const String &p_path) {