Update: I blogged about this. When researching the blog post, I found some potential for improvement; I’ve updated the relevant parts of this answer. For more detail on why I think this is better than all other suggestions here, or the default behavior, read the entire post 🙂
I have now gone with the following approach, which seems to work OK, even if not 100 % compliant with what I was looking for:
-
Create a class
PassthroughExceptionHandler
:public class PassthroughExceptionHandler : IExceptionHandler { public Task HandleAsync(ExceptionHandlerContext context, CancellationToken cancellationToken) { // don't just throw the exception; that will ruin the stack trace var info = ExceptionDispatchInfo.Capture(context.Exception); info.Throw(); return Task.CompletedTask; } }
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Let that class replace the
IExceptionHandler
service of Web API:config.Services.Replace(typeof(IExceptionHandler), new PassthroughExceptionHandler());
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Create a middleware class which does what I want:
public class ExceptionHandlerMiddleware { public override async Task Invoke(IOwinContext context) { try { await Next?.Invoke(context); } catch (Exception ex) { // handle and/or log } } }
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Register that middleware first in the stack:
app.Use<ExceptionHandlerMiddleware>() .UseStageMarker(PipelineStage.Authenticate) // other middlewares omitted for brevity .UseStageMarker(PipelineStage.PreHandlerExecute) .UseWebApi(config);
I will still award the bounty to anyone who comes up with (bounty expired…) I’m still looking for a better solution, which, for example, breaks when an unhandled exception is thrown. (This approach makes VS break when I rethrow the exception in the handler, but the original call stack is lost; I have to set a breakpoint at the faulting line and debug again to be able to intercept the state when an exception is thrown.)