[ImageProxy] Domain whitelist

[jonsmy]

Default behaviour breaks images that load from internal domains, currently there is no way from within FreshRSS to prevent such domains from going through the configured proxy.

[Frenzie]

Unless I'm missing something I don't think that would help much. Mixed content is blocked after all.

[jonsmy]

The internal domains are using custom certs, things load properly when done directly.

[Frenzie]

I'm not opposed to adding a whitelist, but in that case the more obvious solution would seem to be to use the default settings (i.e., don't force proxy HTTPS).

[jonsmy]

I'm mainly interested in caching and allowing intranet clients to be able to view articles without requiring internet access.

[Frenzie]

I think a simple comma-separated text input (with explode()) should probably do the trick?

I mean around here:
https://github.com/FreshRSS/Extensions/blob/9f21984b8c9e75c48496d285795953642a8ec977/xExtension-ImageProxy/extension.php#L72C1-L74C73

Along these lines (NB untested pseudocode, might accidentally run correctly :-)

    $whitelist = "bla.bla,bleep.bla"; // but from userConf
    $parsed_url = parse_url($url);
    $scheme = isset($parsed_url['scheme']) ? $parsed_url['scheme'] : null;
    $host = isset($parsed_url['host']) ? $parsed_url['host'] : null;

    if ($host && in_array($host, explode(',', $whitelist))) {
        return $url;

Please feel free to test and PR; I don't have time to atm and I don't know if I will this week.