Initial commit: HelpDesk ICHN - .NET 10 backend + Next.js 16 frontend

backend/HelpDesk.API/Middleware/ExceptionMiddleware.cs

@@ -0,0 +1,56 @@
+using System.Net;
+using System.Text.Json;
+
+namespace HelpDesk.API.Middleware;
+
+public class ExceptionMiddleware
+{
+    private readonly RequestDelegate _next;
+    private readonly ILogger<ExceptionMiddleware> _logger;
+
+    public ExceptionMiddleware(RequestDelegate next, ILogger<ExceptionMiddleware> logger)
+    {
+        _next = next;
+        _logger = logger;
+    }
+
+    public async Task InvokeAsync(HttpContext context)
+    {
+        try
+        {
+            await _next(context);
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "An unhandled exception occurred: {Message}", ex.Message);
+            await HandleExceptionAsync(context, ex);
+        }
+    }
+
+    private static async Task HandleExceptionAsync(HttpContext context, Exception exception)
+    {
+        context.Response.ContentType = "application/json";
+
+        var (statusCode, message) = exception switch
+        {
+            ArgumentException argEx => (HttpStatusCode.BadRequest, argEx.Message),
+            KeyNotFoundException keyEx => (HttpStatusCode.NotFound, keyEx.Message),
+            UnauthorizedAccessException => (HttpStatusCode.Unauthorized, "Unauthorized access."),
+            InvalidOperationException opEx => (HttpStatusCode.BadRequest, opEx.Message),
+            _ => (HttpStatusCode.InternalServerError, "An unexpected error occurred.")
+        };
+
+        context.Response.StatusCode = (int)statusCode;
+
+        var response = new
+        {
+            error = message,
+            statusCode = (int)statusCode
+        };
+
+        await context.Response.WriteAsync(JsonSerializer.Serialize(response, new JsonSerializerOptions
+        {
+            PropertyNamingPolicy = JsonNamingPolicy.CamelCase
+        }));
+    }
+}