I'm working on an ASP.NET Core application and I've implemented a custom global exception handler using the `IExceptionHandler` interface. My goal is to catch and handle all unhandled exceptions that occur within the application and return a `ProblemDetails` response. Here's the code for my `GlobalExceptionHandler` class:
public class GlobalExceptionHandler : IExceptionHandler {
private readonly ILogger _logger = Log.ForContext(typeof(GlobalExceptionHandler));
public async ValueTask<bool> TryHandleAsync(HttpContext httpContext, Exception exception, CancellationToken cancellationToken)
{
_logger.Error(exception, "Global Exception Handler");
var problemDetails = new ProblemDetails{
Status = (int)HttpStatusCode.InternalServerError,
Title = "An exception occurred",
Detail = exception.Message };
httpContext.Response.StatusCode = problemDetails.Status.Value;
httpContext.Response.ContentType = "application/problem+json";
await httpContext.Response.WriteAsJsonAsync(problemDetails, cancellationToken);
return true;
}
}
However, I noticed that this handler only catches exceptions that are explicitly thrown (e.g., `throw new Exception("...")`) and not those that occur naturally within the application, such as null reference exceptions or other runtime errors. Questions:
1. Why isn't my `IExceptionHandler` implementation catching all exceptions within the application?
3. If `IExceptionHandler` is not suitable for this purpose, what is the recommended way to handle all unhandled exceptions globally without writing custom middleware (the reason we are using Microsoft.AspNetCore.Diagnostics.IExceptionHandler is that it doesn't require us to write a middleware)?
Any guidance or best practices would be greatly appreciated!
IExceptionHandleronly works when middleware is confiure to use it. If your application doesn't have this middleware set up correctly, or if the exception doesn't reach the middleware due to being handled earlier in the pipeline, yourTryHandleAsyncmethod won't be invoked.