WebFinger improvement

[rebelcode-xr]

Right now the WebFinger lookup implementation assumes that "rel": "self" is in position 0 of the array links:

$profile = Helpers::profileFetch($webfinger['links'][0]['href']);
https://github.com/pixelfed/pixelfed/blob/dev/app/Services/WebfingerService.php

            if(isset($json['links']['href'])) {
                $href = $json['links']['href'];
            } else {
                $href = $json['links'][0]['href'];
            }

https://github.com/pixelfed/pixelfed/blob/dev/app/Services/NodeinfoService.php

This might lead to incompatibilities with other implementations.

I found this (sadly I forgot where 🙄) to be a better way:

$found_url = "";
foreach ($data['links'] as $link) {
	if (isset($link['rel'], $link['type'], $link['href'])) {
			if ($link['rel'] == 'self'
					&& $link['type'] == 'application/activity+json'
			) {
					$found_url = $link['href'];
			}
	}
}

[rebelcode-xr]

happy to help 😄