private ValidationError ValidateCvv(ProcessPaymentCommandRequestModel request)
{
if (!string.IsNullOrWhiteSpace(request.CVV))
{
if (!request.CVV.All(Char.IsDigit))
{
return(new ValidationError(nameof(request.CVV), "Invalid CVV"));
}
else if (request.CVV.Length != 3 && request.CVV.Length != 4)
{
return(new ValidationError(nameof(request.CVV), "Invalid CVV"));
}
}
return(null);
}
public IEnumerable <ValidationError> Validate(ProcessPaymentCommandRequestModel request)
{
if (request == null)
{
throw new ArgumentNullException();
}
if (!_creditCardNumberValidator.IsCreditCardNumberValid(request.CreditCardNumber))
{
yield return(new ValidationError(nameof(request.CreditCardNumber), "Credit card number is invalid"));
}
if (!_currencyValidator.IsCurrencySupported(request.Currency))
{
yield return(new ValidationError(nameof(request.Currency), "Currency not supported"));
}
var expiryDateValidationError = ValidateExpiryDate(request);
if (expiryDateValidationError != null)
{
yield return(expiryDateValidationError);
}
var cvvValidationError = ValidateCvv(request);
if (cvvValidationError != null)
{
yield return(cvvValidationError);
}
if (request.Amount <= 0)
{
yield return(new ValidationError(nameof(request.Amount), "Amount must be greater than zero"));
}
if (string.IsNullOrWhiteSpace(request.CustomerName))
{
yield return(new ValidationError(nameof(request.CustomerName), "Customer name must be provided"));
}
}
public async Task <ProcessPaymentCommandResultModel> ExecuteAsync(ProcessPaymentCommandRequestModel request)
{
var errors = _processPaymentCommandRequestValidator.Validate(request);
if (errors.Any())
{
return(new ProcessPaymentCommandResultModel
{
Notification = new Notification(errors)
});
}
var(bankTransactionId, status, bankError) = await PostRequestToBankAsync(request);
var paymentRequest = new PaymentRequest
{
Amount = request.Amount,
CreditCardNumber = request.CreditCardNumber,
Currency = request.Currency,
CustomerName = request.CustomerName,
CVV = request.CVV,
ExpiryMonth = request.ExpiryMonth,
ExpiryYear = request.ExpiryYear,
Reference = request.Reference,
Status = status,
BankErrorDescription = bankError,
BankTransactionId = bankTransactionId
};
_dbContext.PaymentRequests.Add(paymentRequest);
await _dbContext.SaveChangesAsync();
return(new ProcessPaymentCommandResultModel
{
PaymentRequestId = paymentRequest.Id,
Status = status
});
}
private ValidationError ValidateExpiryDate(ProcessPaymentCommandRequestModel request)
{
if (DateTime.TryParseExact($"{request.ExpiryYear:0000}-{request.ExpiryMonth:00}-01T00:00:00.0000000Z",
"yyyy-MM-dd'T'HH:mm:ss.fffffff'Z'",
CultureInfo.InvariantCulture,
DateTimeStyles.AssumeUniversal | DateTimeStyles.AdjustToUniversal,
out DateTime expiryDate))
{
var now = _dateTimeProvider.UtcNow();
var firstOfCurrentMonth = new DateTime(now.Year, now.Month, 1, 0, 0, 0, DateTimeKind.Utc);
if (expiryDate.Date <= firstOfCurrentMonth.Date)
{
return(new ValidationError(null, "Card has expired"));
}
}
else
{
return(new ValidationError(null, "Invalid expiry date"));
}
return(null);
}
private async Task <(Guid?Id, PaymentRequestStatus Status, string Error)> PostRequestToBankAsync(ProcessPaymentCommandRequestModel request)
{
try
{
var bankResult = await _acmeBankApi.ProcessPayment(request.CreditCardNumber,
request.CVV,
request.ExpiryMonth,
request.ExpiryYear,
request.Amount,
request.Currency,
request.CustomerName);
return(bankResult.Id,
bankResult.WasSuccessful ? PaymentRequestStatus.Successful : PaymentRequestStatus.Unsuccessful,
bankResult.Error);
}
catch (Exception)
{
return(null, PaymentRequestStatus.UnableToProcess, "Unable to process with bank");
}
}