Hi, we’d like to request a new track called “20” to publish system snaps that will use core20 as base, which are:
bluez
network-manager
modem-manager
We plan to follow the same convention as gadget/kernel snaps that have the base as track, like pc and pc-kernel. This changes the convention that we were previously following, which was based on upstream version. The reasons are:
These snaps are closely tied to a given UC release. These are system daemons that control parts of the system that need to be in sync with the core snap. For instance, DNS management changed between UC16 and UC18, and NM takes control of this when installed in the system.
Now these snaps use the equivalent debian package sources for building: we plan to track Ubuntu releases, not upstream versions. As occasionally the upstream version of a package for a given Ubuntu series can be upgraded, it is better to base the track on the series instead of in a concrete version. See this publishing history as an example of an occurrence of this kind (for Bionic).
Due to the previous reasons, it is more intuitive for users to see the UC release as a track, so for a given UC they have a hint of the track to follow. Versions do not expose that information immediately.
What do you plan to do with the existing tracks? for reference, network-manager has 1.10, while modem-manager has 1.9 and 1.10.
Your new scheme makes sense within the context of UC releases but as a user I unfortunately find it somewhat confusing.
Will these snaps be included in Ubuntu Core systems?
Can I use them on classic systems? if so, how do I choose which one depending on my version of Ubuntu?
can I install from a non-matching track? i.e. what happens if I install 1.10 on an UC20 system, or try to install 22 on my UC20 system or 20 on my UC22 system in the future?
Will these ship with the system starting on UC20 or something similar?
I’m +1 on granting these tracks as they do make sense as stated but I would suggest planning for users having the same questions I had
Yes, I know we have those 1.10 tracks for NM and MM (MM 1.9 is closed). Eventually the plan would be to migrate those users to “18” tracks - not sure how we will do that though. In fact, if you are fine with creating “20” tracks, I would like to extend the request to create the “18” ones too .
These snaps are mainly for Ubuntu Core and we have had some internal discussions on whether we should prevent using them on classic systems.
You can install in the different combinations you mention, at the price of installing the corresponding base snap if not already in the system (1.10 on UC20 will pull core18, for instance). But, due to the high integration that these snaps have with the system, there can be problems like the DNS one I mentioned - this concrete one was fixed with a workaround, but we cannot really guarantee that installing a snap on UCXX not based on the matching Ubuntu release daemon will work perfectly.
The snaps will not be part of the minimal UC20 system, but most of the images we produce for commercial systems include at least the network-manager snap, and bluez and modem-manager are included quite often.
I’m ok with this, but again worried about breaking “user” compatibility in how users find snaps, and expect to find them. I think this can work well provided a mechanism is introduced to allow users to simply and reliably map snaps to UC releases.
About finding snaps in an easier way, maybe having tracks called “core20” instead of just “20” would help. I see that pc-kernel and pc (gadget) snaps, for instance, use “20” as track, that is why I have asked for tracks named “20”, but that seems a bit terse tbh. coreXX is more explicit and would help users, but I’m not sure if we are willing to change the convention at this point in time.
My apologies, this totally fell through a very deep crack
I have created the requested 20 track for those 3 snaps, based on Igor’s comment and my initial +1, I’m leaving the hard part of coordinating this and ensuring it doesn’t become a mess, to you But do let us know if we can help in any way.
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I have created the requested