Disable returnLastResortErrorResponse to allow the Express error handler to kick in

[haines]

In the Remix Express adapter, there's a catch that forwards errors to the next middleware in the stack:

remix/packages/remix-express/server.ts

Lines 59 to 61 in 58ac1e9

	// Express doesn't support async functions, so we have to pass along the
	// error manually using next().
	next(error);

This is good, because I can register an error handler in my Express app to display a branded "server error" page.

However, returnLastResortErrorResponse means that errors in the request handler aren't thrown, so that catch isn't triggered and the Express error handler isn't called.

remix/packages/remix-server-runtime/server.ts

Lines 674 to 688 in 58ac1e9

	function returnLastResortErrorResponse(error: any, serverMode?: ServerMode) {
	let message = "Unexpected Server Error";
	if (serverMode !== ServerMode.Production) {
	message += `\n\n${String(error)}`;
	}
	// Good grief folks, get your act together 😂!
	return new Response(message, {
	status: 500,
	headers: {
	"Content-Type": "text/plain",
	},
	});
	}

I think it would be nice if the Remix Express adapter disabled returnLastResortErrorResponse, causing the error to be thrown from the request handler and passed on to Express instead. The default Express error handler does pretty much exactly the same thing as returnLastResortErrorResponse anyway, so even in apps without a custom error handler this would be a reasonable behaviour (i.e. it would not have to be configurable externally).