Feature request: preload track metadata for tracks likely to be activated

[climategadgets]

Existing Behavior

Clicking on the "hamburger icon" of the tracks on the home page list, or search result list, causes a request to the server and usually a noticeable delay before the context menu appears.

Desirable Behavior

Clicking on the "hamburger icon" causes the context menu to appear immediately.

Additional Information

It seems that this is a regression that appeared within last year or two, previously the context menu was popping up without delay.

Either way, meta information for the items on the home page can even be loaded once as they're added there and stored in persistent properties so it is available without a network call, and meta information for search results can be loaded in background especially if the number of hits is not large.

[kaaholst]

Yes, it would be nice to get rid of the delay for the context menu.

We can try this, however the issue would be to guess which items to preload the context menu for.
The easy target is the context menu on the now playing screen, for the currently playing song. However, it does not seem to be what you request.
For the screens with lists of items, we could try to load the context menu in the background for the currently visible items, like we do for the artwork. Provided this does not put too much stress on the server, or slow other things down.

Regarding whether it is a regression, I think it's more likely due to a server upgrade or perhaps local network / performance issues. It is correct that there was a change in February 2023 where the context menu is shown in a bottom sheet instead of a popup menu. While waiting for the context menu, this bottom sheet will have a horizontal progress indicator and will not expand until we get the context menu from the server. Previously, the context menu was shown in a popup menu, and the context menu button would change to a circular progress indicator while waiting for the context menu. So it may look different, but the actual time it takes for the context menu to show, should be the same, given that the server replies at the same rate.

The context menus, unfortunately, can't be stored in persistent properties. The reason is that the commands to get them from the server is generated by the preceding command, which gives us the items Squeezer are currently showing. The command, to give us the items, is again dependent on the previous result from tapping an item. All these commands eventually depends on the player, the LMS settings the music database and finally the LMS version. Keeping track of all these might in theory be possible, but it will be error-prone and a maintenance nightmare. Also, there is currently a bug in LMS which causes it to claim that the music database is changed whenever a music folder is opened, so we would have to drop context menu cache.

PS
We do cache the artwork in persistent storage, because the commands to get those appear to be stable.