add ExceptionHandlingMiddleware

AB-API/Middleware/ExceptionHandlingMiddleware.cs

@@ -0,0 +1,38 @@
+using AB.Domain.Exceptions;
+using System.Text.Json;
+
+namespace AB_API.Middleware
+{
+    public class ExceptionHandlingMiddleware : IMiddleware
+    {
+        public async Task InvokeAsync(HttpContext context, RequestDelegate next)
+        {
+            try
+            {
+                await next(context);
+            }
+            catch (Exception ex)
+            {
+                await HandleExceptionAsync(context, ex);
+            }
+        }
+
+        private async Task HandleExceptionAsync(HttpContext httpContext, Exception ex)
+        {
+            httpContext.Response.ContentType = "application/json";
+
+            httpContext.Response.StatusCode = ex switch
+            {
+                NotFoundException => StatusCodes.Status404NotFound,
+                _ => StatusCodes.Status400BadRequest
+            };
+
+            var response = new
+            {
+                error = ex.Message
+            };
+
+            await httpContext.Response.WriteAsJsonAsync(response);
+        }
+    }
+}