How can i get access to the error returned by the handler using a middleware?

[barata0]

Let´s suppose I want to log every error returned by the handlers
I believe the best way to do this is using a middleware and if there is an error log it.

Best I could think about is this:

		log.Printf("Error: %v", ctx.Context().Err())
	}

But ctx.Context.Err is nil.