Display server error in the page

[zonia3000]

Hi,
currently, if the server replies with an error, vizarr displays a black page. We would like to display an informative error to the user, so we are proposing these changes.

Notice that, since we are also using authentication, we would also like to display 403 Forbidden messages, but this is not possible at the moment since Zarrita handles 403 and 404 in the same way.

Here is the handle_response function in zarrita.js (see https://github.com/manzt/zarrita.js/blob/7ff33a59803ee37cbeec5b4aa61528d8bd021691/packages/storage/src/fetch.ts#L19):

async function handle_response(
	response: Response,
): Promise<Uint8Array | undefined> {
	if (response.status === 404 || response.status === 403) {
		return undefined;
	}
	if (response.status === 200 || response.status === 206) {
		return new Uint8Array(await response.arrayBuffer());
	}
	throw new Error(
		`Unexpected response status ${response.status} ${response.statusText}`,
	);
}

@manzt Would it be possible to throw an error also for the 403 case?

Thanks

[manzt]

Thanks for the contribution. It would be nice to have some kind of toast message but I think this is a better helper to end users than what we currently have (opening the console).

I might take a stab later to toy around with the UI but let's merge for now.

Notice that, since we are also using authentication, we would also like to display 403 Forbidden messages, but this is not possible at the moment since Zarrita handles 403 and 404 in the same way.

I didn't realize this was a behavior change from Zarr.js - so thanks for pointing this out. I'm trying to remember why we also handled 403 this way, but can't find anything. Let me ask some folks in the group, but I think a PR to zarrita changing the default behavior to only returning undefined for 404 would be preferrable.