JsonExceptionMiddleware in ASP.NET Core 3

[rochapablo]

I'm trying to follow the example, but it seems that app.UseExceptionHandler it's called only when I remove app.UseAuthorization, but I do need UseAuthorization. What could I be missing?

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    // Serialize all exceptions to JSON
    var jsonExceptionMiddleware = new JsonExceptionMiddleware(app.ApplicationServices.GetRequiredService<Microsoft.AspNetCore.Hosting.IHostingEnvironment>());
    app.UseExceptionHandler(new ExceptionHandlerOptions { ExceptionHandler = jsonExceptionMiddleware.Invoke });

    app.UseHsts();

    app.UseRouting();

    app.UseHttpsRedirection();            

    app.UseCors(x => x
        .AllowAnyOrigin()
        .AllowAnyMethod()
        .AllowAnyHeader());            

    app.UseAuthentication();

    app.UseAuthorization();

    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });            

    app.UseResponseCaching();
}

When I have status 401 for example, It should be calling JsonExceptionMiddleware.Invoke before the request response, but the body it's empty.

[nbarbettini]

401 (authorization failure) isn't the same thing as an unhandled exception. UseExceptionHandler is only invoked when an exception is thrown by some code in your application. Authorization failures don't throw exceptions, though.

Are you trying to customize the payload that's returned along with 401?