Add Dashboard Icons support

[2q2code]

• defined new type IconSource and constants, presently supporting:
  • LocalFile
  • SimpleIcon
  • DashboardIcon
• added new field to bookmarks and monitors to hold IconSource
• adjusted IsSimpleIcon to get truthiness from IconSource field
• generalised toSimpleIconIfPrefixed into toRemoteResourceIconIfPrefixed, adding support for walkxcode's dashboard icons via CDN (svg)

[2q2code]

I forked this from main, but when I went to do the PR, it said to use the latest release branch, so I'm not sure what to do about this, however, it builds, and has been tested, using the main branch. It does not have any negative effect on existing glance.yml configs (at least for my own config), but given the simplicity of the modification, it should have no bad effects whatsoever.

[2q2code]

Having a few minutes to think, I would probably rename the constant LocalFile and the reference to RemoteResourceIcon to something like URI and IconShortCode or something. Meh.

[2q2code]

Made the noted changes above, and also added support to use either SVG or PNG version of DashBoardIcons. It makes more sense now so I can stop touching it. :sweat_smile:

[2q2code]

The extended notation mechanism is noted in code comments in fields.go.

[svilenmarkov]

Hey, thanks for contributing!

To avoid having to duplicate the same logic in future widgets that also have user provided icons, I think what might make more sense is to have a custom type that keeps the logic and data in one place:

type CustomIcon struct {
    URL        string
    IsFlatIcon bool
}

func (i *CustomIcon) UnmarshalYAML(node *yaml.Node) error {
    var value string
    if err := node.Decode(&value); err != nil {
        return err
    }

    prefix, icon, found := strings.Cut(value, ":")
    if !found {
        i.URL = value
        return nil
    }

    // the rest of the code from toIconURIIfPrefixed

    return nil
}

This could then easily be used in structs as:

struct {
    Icon CustomIcon `yaml:"icon"`
}

And wouldn't need iterating and applying things manually in each widget like this anymore:

link.Icon, link.IconSource = toIconURIIfPrefixed(link.Icon)
link.IsSimpleIcon = link.IconSource == SimpleIcon

(though would require tweaking the current templates a little)

I'll get that done and merged by the end of the week unless you'd like to make this change yourself.

[2q2code]

Your approach sounds solid. I've no more time to give this week, so I'll leave it to you. I did have some other ideas around the flat icons: allowing this to be user set or forced off if already on due to simple icon syntax, and also, an idea not fully formed yet, is the use of the colour values on simple icons' website to tint the icons their trademark colours if desired, or another colour entirely. Then the flag would become monochrome perhaps instead of flat. I have other ideas but another time. Have a good weekend. Nice to meet you!

[svilenmarkov]

No worries, got it sorted out. It should be much easier to make changes to the icons implementation now, should you want to try realizing those ideas later down the line. Thanks again for contributing and have a nice weekend!