//inject the services public BaseService(IGiftVoucherService giftService, IDiscountVoucherService discountService, IValueVoucherService valueService, IVoucherRepository voucherRepository, ILogger <BaseService> logger) { this._giftVoucherService = giftService; this._discountVoucherService = discountService; this._valueVoucherService = valueService; this._baseRepository = voucherRepository; this._logger = logger; }