Allow Plaintext URLs In Flatpak App Descriptions

[Zishan-Rahman]

Previously, flatpak-builder-lint used a patched version of appstream-glib that allowed app descriptions to contain plaintext URLs. This was extremely useful, especially when it came to directing end users to issues they may face, including Flatpak-specific ones that couldn't be reproduced with native versions of the apps on Flathub, as well as clearing up certain discrepancies to end users. For example, org.processing.processingide, org.godotengine.Godot and com.inform7.IDE are three Flatpak apps that, at present, have plaintext URLs in their app descriptions that serve the aforementioned purposes.

With the recent change to libappstream, to allow for, among other things, updated license expressions (and a welcome change indeed), it seems that the linter now prevents app descriptions in appdata.xml files from containing plaintext URLs, and as a result several PRs I'm working on at the moment have been affected. Most, if not all, of them would otherwise build successfully.

I'm familiar with neither appstream-glib nor libappstream as to how either of them work or are programmed, so at present I've no idea how I'd approach fixing this issue. I'm also not sure if this issue is more appropriate for the flatpak-builder-lint repository or for this one. For all I know, we could either patch libappstream to skip plaintext URL in description checks or disable said checks in some other way. Nonetheless, I do think this is a very important issue that should be looked into somehow.

Some PRs that are affected by this (all opened by me): flathub/org.strawberrymusicplayer.strawberry#75, flathub/org.godotengine.Godot#159. flathub/org.godotengine.Godot#158

[Erick555]

This is already done, recent errors in your PR are about something different

{
    "errors": [
        "appstream-missing-developer-name",
        "appstream-failed-validation"
    ],
    "appstream": [
        "E: org.godotengine.Godot.desktop:~: desktop-app-launchable-omitted"
    ],
    "message": "Please consult the documentation at https://docs.flathub.org/docs/for-app-authors/linter"
}

[bbhtt]

The commit stage was stuck in an older linter version, should be fixed now.

[bbhtt]

flathub/org.godotengine.Godot#158 (comment)