Question

So I have modified the todo service that gives me a response.

When I deliberately throw an unhandled error to test ServiceExceptionHandler code below, if I use the default /Backbone.Todos/todo/1?format=json, it is fine.

But if I use /Backbone.Todos/todo/1?format=xml, it says:

XML Parsing Error: not well-formed Location:
/Backbone.Todos/todo/1 Line Number 1, Column 2:

Here is my code:

public class AppHost : AppHostBase {
    public override void Configure(Funq.Container container) {
        //Unhandled errors
        this.ServiceExceptionHandler = (req, ex) => {
            var res = new { //i return a dynamic object here ... and it doesn't work
                Result = null as object,
                ResponseStatus = new ResponseStatus() {
                ErrorCode = "Error",
                Message = "Not available",
                StackTrace = "Not available"
                }
            };
            return res;
        };
    //...
    }
//....
}

//My normal request/response dtos look like this:
//-----------------------------------------
[Route("/todo/{id}", "GET")] //display req
public class GetTodo : IReturn<TodoResponse> {
    public long Id { get; set; }
}
public class TodoResponse : IHasResponseStatus {
    public IList<Todo> Result { get; set; }
    public ResponseStatus ResponseStatus { get; set; }
}

The thing is, when error occured I can’t construct a correct type of response without knowing what type it is. I only get incoming Request and Exception as paramaters, but not Response type.

Answer 1

I suspect the error is because XML cannot automatically serialize dynamic objects in .net.

I not entirely sure I know what you are trying to do but you could try using the built in utilities to handle the exception then modify it as you want.

this.ServiceExceptionHandler = (req, ex) =>
{
    var responseStatus = ex.ToResponseStatus();
    var errorResponse = ServiceStack.ServiceHost.DtoUtils.CreateErrorResponse(req, ex, responseStatus);
    return errorResponse;
};