1 files changed, 20 insertions, 0 deletions
diff --git a/Validators/NameAttribute.cs b/Validators/NameAttribute.cs
new file mode 100644
index 0000000..2f1a5ae
--- /dev/null
+++ b/Validators/NameAttribute.cs
@@ -0,0 +1,20 @@
+using System.ComponentModel.DataAnnotations;
+using LibraryAPI.Models;
+
+namespace LibraryAPI.Validators {
+    public class NameAttribute : ValidationAttribute {
+        public string[] valid_names = { "regular", "librarian" };
+	public string GetErrorMessage() {
+            return "Group name must be \"regular\" or \"librarian\"";
+        }
+
+	protected override ValidationResult? IsValid(object? value, ValidationContext validationContext) {
+	    var group = (Group) validationContext.ObjectInstance;
+
+	    if(Array.Exists(valid_names, s => s == group.Name))
+		return ValidationResult.Success;
+
+	    return new ValidationResult(GetErrorMessage());
+	}
+    }
+}