snapd should track what user installed what, and use the appropriate macaroon in auto-refresh

[John Lenton]

Currently if a user installs a private snap, the snap never gets refreshed: the refresh doesn't use the user's macaroon, so no refresh exists.

The goal would be to have a single request going to the store with the appropriate macaroon(s).

As a first step we should start looping over the users, and doing a refresh per user.

We should also start tracking what user installed what, and if all private or buyable snaps have a user associated, then we just loop over those users instead of over all of them.

We might be able to migrate from the first case to the second by back-filling with what works.

[Samuele Pedroni (pedronis)]

we need to improve our spread tests situation regarding private snaps when tackling this

[Samuele Pedroni (pedronis)]

In 2.30 we started tracking for each snap the userID of the installing user, snap refresh foo will also set this for a snap that didn't have yet the information.

The plan now is to use that information to refresh snaps in groups with the credentials of their installing users.

[Samuele Pedroni (pedronis)]

started proposing:

https://github.com/snapcore/snapd/pull/4392

[Samuele Pedroni (pedronis)]

a fix for this has now landed (will be in 2.31), in the end we don’t group but query for all snaps for all user creds (to make a best effort to respect validation with the current APIs)