Extension/GJS/API: I don't get channels of a snap

fthx · December 19, 2025, 8:31pm

Hi all,

I just made Snap Menu GNOME extension. https://extensions.gnome.org/extension/9040/snap-menu/

It uses snapd2 library and works quite well. BUT I did not success to get channels. I get a void array with snap.get_channels() or an error with snap.channels.

github.com/fthx/snap-menu

extension.js

95b1703c2


      
          
          _showSnapInfo(snap) {
              this.menu?.close();
          
              const title = snap?.title
              const summary = snap?.summary ?? 'N/A';
              const version = snap?.version ?? 'N/A';
              const revision = snap?.revision ?? 'N/A';
              const channel = snap?.channel ?? 'N/A';
              const confinement = this._getSnapConfinementName(snap?.confinement) ?? 'N/A';
              //const channels = snap?.channels?.map(channel => channel.name).join(' ') ?? 'N/A';
          
              this._showTextDialog(
                  'Snap menu extension :: Info',
                  [
                      `<b>Name</b>\u2003${title}`,
                      `<b>Summary</b>\u2003${summary}`,
                      '',
                      `<b>Version</b>\u2003${version} (${revision})`,
                      `<b>Channel</b>\u2003${channel}`,
                      `<b>Confinement</b>\u2003${confinement}`,

I need help here as I do not understand how it works. I tried to get channels sync rather than async but the issue is the same.

I tried to make a dedicated function but same issue again:

_getSnapChannels(snap) {
            this._snapdClient?.find_async(
                Snapd.FindFlags.SCOPE_WIDE,
                snap?.name,
                null,
                (client, result) => {
                    const storeSnap = client.find_finish(result);
                    log(storeSnap);
                    return storeSnap[0][0]?.channels;
                }
            );

Thanks!

Related: https://discourse.ubuntu.com/t/snap-gnome-extension/73774

fthx · December 25, 2025, 11:09am

https://api.snapcraft.io/v2/snaps/find?architecture=amd64&confinement=strict%2Cclassic&fields=base%2Cconfinement%2Clinks%2Ccontact%2Cdescription%2Cdownload%2Clicense%2Cprices%2Cprivate%2Cpublisher%2Crevision%2Csummary%2Ctitle%2Ctype%2Cversion%2Cwebsite%2Cstore-url%2Cmedia%2Ccommon-ids%2Ccategories%2Cchannel&q=gimp

returns:

{"error-list":[{"code":"missing-header","message":"Snap-Device-Series header is required."}]}

and I’m stuck here.

soumyaDghosh · December 25, 2025, 6:57pm

Why are you making the request to api.snapcraft.io?

fthx · December 26, 2025, 12:24am

That’s the find_sync function.