using System.Collections.Generic; using System.ComponentModel.DataAnnotations; using System.Linq; using UserService.Infrastructure.DataModels; namespace UserService.Infrastructure { public static class Validators { public static bool? ValidateEmail(string? mailAddress) { if (string.IsNullOrEmpty(mailAddress)) return null; return new EmailAddressAttribute().IsValid(mailAddress); } public static bool? ValidateCommonName(string? commonName, IEnumerable users) { if (string.IsNullOrEmpty(commonName)) return false; return users.All(x => x.CommonName != commonName); } } }