Error Handling
If an exception occurs while a request is handled, the server will render the exception into a HTML page that informs the client about the issue.
If you would like to send cutom HTTP responses for exceptions, you can add
the ErrorHandler concern with a custom IErrorMapper.
The following example will generate a JSON response for errors and missing content:
var errorHandling = ErrorHandler.From(new JsonErrorMapper());
var api = Layout.Create()
.AddService<...>()
.Add(errorHandling);
public record ErrorModel(String Message);
public class JsonErrorMapper : IErrorMapper<Exception>
{
public ValueTask<IResponse?> GetNotFound(IRequest request, IHandler handler)
{
var errorModel = new ErrorModel("The requested content was not found");
// hint: return null here to render the default error page of the server
return new(GetResponse(request, ResponseStatus.NotFound, errorModel));
}
public ValueTask<IResponse?> Map(IRequest request, IHandler handler, Exception error)
{
var errorModel = new ErrorModel(error.Message);
if (error is ProviderException providerException)
{
return new(GetResponse(request, providerException.Status, errorModel));
}
return new(GetResponse(request, ResponseStatus.InternalServerError, errorModel));
}
private static IResponse GetResponse(IRequest request, ResponseStatus status, ErrorModel model)
{
return request.Respond()
.Status(status)
.Content(new JsonContent(model, new()))
.Type(ContentType.ApplicationJson)
.Build()
}
}