added validators in project

BookHive/Validators/Authors/CreateAuthorDtoValidator.cs

@@ -0,0 +1,45 @@
+using BookHive.DTO.Author;
+using FastEndpoints;
+using FluentValidation;
+
+namespace BookHive.Validators.Authors;
+
+public class CreateAuthorDtoValidator : Validator<CreateAuthorDto>
+{
+    public CreateAuthorDtoValidator()
+    {
+        RuleFor(x => x.FirstName)
+            .NotEmpty()
+            .WithMessage("First name is required.")
+            .MaximumLength(100)
+            .WithMessage("First name cannot exceed 100 characters.")
+            .MinimumLength(2)
+            .WithMessage("First name must exceed 2 characters.");
+        
+        RuleFor(x => x.LastName)
+            .NotEmpty()
+            .WithMessage("Last name is required.")
+            .MaximumLength(100)
+            .WithMessage("Last name cannot exceed 100 characters.")
+            .MinimumLength(2)
+            .WithMessage("Last name must exceed 2 characters.");
+        
+        RuleFor(x => x.Biography)
+            .MaximumLength(2000)
+            .WithMessage("Biography cannot exceed 2000 characters.")
+            .MinimumLength(2)
+            .WithMessage("Biography must exceed 2 characters.");
+        
+        RuleFor(x => x.BirthDate)
+            .NotEmpty()
+            .WithMessage("Birth date is required.")
+            .LessThan(DateOnly.FromDateTime(DateTime.Now))
+            .WithMessage("Birth date cannot be in the future.");
+        
+        RuleFor(x => x.Nationality)
+            .NotEmpty()
+            .WithMessage("Nationality is required.")
+            .MaximumLength(60)
+            .WithMessage("Nationality cannot exceed 60 characters.");
+    }
+}