Backend login and register

src/Application/Validators/UserUpdateRequestValidator.cs

@@ -0,0 +1,21 @@
+using Application.Models;
+using FluentValidation;
+
+namespace Application.Validators;
+
+public class UserUpdateRequestValidator : AbstractValidator<UserUpdateRequest>
+{
+    public UserUpdateRequestValidator()
+    {
+        RuleFor(x => x.Username)
+            .NotEmpty().WithMessage("Username is required.")
+            .MaximumLength(50).WithMessage(user => "Username must not exceed 50 characters.");
+
+        RuleFor(x => x.Email)
+            .NotEmpty().WithMessage("Email is required.")
+            .EmailAddress().WithMessage("Email is invalid.");
+
+        RuleFor(x => x.Id)
+            .NotEmpty().GreaterThan(0).WithMessage("Id is required.");
+    }
+}