ServiceStack doesn't populate error responses - servicestack

Question

We're working on a project using ServiceStack (loving it) but need some help with a strange problem. In our project we throw or return various types of HttpError with ErrorResponse and ResponseStatus objects using a helper method.
It follows the pattern described here. Something like this:
protected HttpError BusinessError(string summaryMessage = "Some generic validation summary.")
{
return new HttpError(HttpStatusCode.BadRequest, "MyValidationType", summaryMessage)
{
Response = new ErrorResponse
{
ResponseStatus = new ResponseStatus
{
ErrorCode = "MyValidationType",
Message = summaryMessage,
Errors = new List<ResponseError>()
},
}
};
}
In a service call we would use it like so:
throw BusinessError("Help I've fallen and can't get up!");
This would work a treat, and we'd feed it in to the ss-validation JS library to render our validation messages. Worked fine.
The problem is that now ServiceStack won't serialize any of the HttpError's details into the response. All we get is a response with the 400 status code, the 'MyValidationType' error code, and empty JSON response {}.
I've tried playing with combinations of throwing/returning the error and switching the service method's return type to object etc, but nothing seems to make a difference. To be honest I'm not sure what we could have changed in our project to cause this behavior.
I'd appreciate any advice or pointers as to what could cause this?

Answer 1

This can happen if you're using a {RequestName} and {RequestName}Response naming convention and the Response DTO does not have a ResponseStatus property:
The {RequestDto}Response is returned, regardless of the service method's response type. If the {RequestDto}Response DTO has a ResponseStatus property, it is populated otherwise no ResponseStatus will be returned. (If you have decorated the {ResponseDto}Response class and properties with [DataContract]/[DataMember] attributes, then ResponseStatus also needs to be decorated, to get populated).
In which case the solution is just to add a ResponseStatus property to the Response DTO:
public class RequestNameResponse
{
public ResponseStatus ResponseStatus { get; set; }
}