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@jchannon
Last active Aug 31, 2017
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What would you like to do?
This will handle Nancy content negotiation on errors so the client receives JSON, XML or HTML based on the client Accept headers
public class CustomBootstrapper : DefaultNancyBootstrapper
{
protected override void ApplicationStartup(TinyIoCContainer container, IPipelines pipelines)
{
pipelines.OnError += (ctx, exception) =>
{
ctx.Items.Add("OnErrorException", exception);
return null;
};
}
}
public class Error
{
public string ErrorMessage { get; set; }
public string FullException { get; set; }
}
public class ErrorStatusCodeHandler : IStatusCodeHandler
{
private readonly IResponseNegotiator responseNegotiator;
public ErrorStatusCodeHandler(IResponseNegotiator responseNegotiator)
{
this.responseNegotiator = responseNegotiator;
}
public bool HandlesStatusCode(HttpStatusCode statusCode, NancyContext context)
{
return statusCode == HttpStatusCode.InternalServerError;
}
public void Handle(HttpStatusCode statusCode, NancyContext context)
{
var response = new Negotiator(context);
Error error = null;
if (context.Items.ContainsKey("OnErrorException"))
{
var exception = context.Items["OnErrorException"] as Exception;
error = new Error { ErrorMessage = exception.Message, FullException = exception.ToString() };
}
response.WithModel(new ErrorPageViewModel
{
Title = "Sorry, something went wrong",
Summary = error == null ? "An unexpected error occurred." : error.ErrorMessage,
Details = error == null ? null : error.FullException
})
.WithStatusCode(statusCode)
.WithView("Error");
var errorresponse = responseNegotiator.NegotiateResponse(response, context);
context.Response = errorresponse;
}
}
@JeanTerblanche

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@JeanTerblanche JeanTerblanche commented Mar 22, 2015

Thanks, this is really great but it doesn't seem to work with Hosting.AspNet - any ideas?

@MacsDickinson

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@MacsDickinson MacsDickinson commented Mar 28, 2015

@JeanTerblanche It may not be the same issue as you are seeing but I needed to call errorresponse.PreExecute(context); to prevent a null reference exception within Nancy.Responses.MaterialisingResponse.

L35 of errorstatuscodehandler.cs becomes

var errorresponse = responseNegotiator.NegotiateResponse(response, context);
errorresponse.PreExecute(context);
context.Response = errorresponse;
@liddellj

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@liddellj liddellj commented Apr 29, 2015

@MacsDickinson thank you very much - I was encountering the same issue and this fixed it.

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