More changes to the endpoint auto setup

TOOHUCardAPI/Controllers/MethodBasedController.cs

@@ -0,0 +1,54 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc;
+using TOOHUCardAPI.Data;
+
+using MethodMap = System.Collections.Generic.Dictionary<string, System.Reflection.MethodInfo>;
+namespace TOOHUCardAPI.Controllers
+{
+    public class MethodBasedController : ControllerBase
+    {
+        public delegate Task<object> EndpointHandler(string requestBody);
+        private static Dictionary<Type, MethodMap> MethodMapByType;
+        
+        protected Task<object> InvokeEndpointHandlerForMethod<T>(object _this, string method, string body)
+        {
+            MethodMap registeredEndpointHandlers = GetMethodMapForType<T>();
+            if (registeredEndpointHandlers.ContainsKey(method))
+            {
+                return ((EndpointHandler) registeredEndpointHandlers[method]
+                    .CreateDelegate(typeof(EndpointHandler), _this)).Invoke(body);
+            }
+            throw new MissingEndpointHandlerException(method);
+        }
+
+        private MethodMap GetMethodMapForType<T>()
+        {
+            if (!MethodMapByType.ContainsKey(typeof(T)))
+            {
+                RegisterEndpointHandlers<T>();
+            }
+
+            return MethodMapByType[typeof(T)];
+        }
+
+        private static MethodMap RegisterEndpointHandlers<T>()
+        {
+            MethodInfo[] methods = typeof(T).GetMethods();
+            return methods
+                .Aggregate(new MethodMap(), (handlers, m) =>
+                {
+                    Attribute attr = m.GetCustomAttribute(typeof(EndpointHandlerAttribute), false);
+                    if (attr != null)
+                    {
+                        EndpointHandlerAttribute e = (EndpointHandlerAttribute) attr;
+                        handlers.Add(e.Method, m);
+                    }
+                    return handlers;
+                });
+        }
+    }
+}