public void Connect(string key) { if (string.IsNullOrWhiteSpace(key)) { throw new ArgumentNullException(nameof(key)); } _credentialsRepository.SaveIfttt(key); if (_deviceRepository.Exists("IFTTT", DeviceCapability.WebService)) { return; } var iftttService = new Device { Identifier = Guid.NewGuid(), Name = "IFTTT", Capability = DeviceCapability.WebService, Type = DeviceType.Ifttt }; _deviceRepository.Add(iftttService); }