Row Validation

DataAnnotations attributes on TRow are validated during binding, one row at a time. All errors are collected before the handler is invoked and surfaced as an RFC 9457 ValidationProblem response by CsvBindingExceptionFilter.

Error keys follow the pattern "row {n}: {MemberName}":

{
  "status": 400,
  "errors": {
    "row 3: Email": ["The Email field is not a valid e-mail address."],
    "row 5: Name":  ["The Name field is required."]
  }
}

Registering the filter

Register CsvBindingExceptionFilter on any endpoint that accepts a CsvRequest<TRow> parameter:

config.Post("/users/import").AddFilter<CsvBindingExceptionFilter>();

For general DataAnnotations validation on request types, see the Validation guide.