'snap refresh' is silent about changes in progress

[Mark Shuttleworth]

A small improvement to observability, low priority but may also be generalised.

This morning I noticed that there was a new VLC snap being distributed (it has lots of users so it shows up in the charts). I did snap info and saw that I had an older version of VLC than the current store.

$ snap info vlc
name: vlc
summary: The ultimate media player
[...]
tracking: stable
installed: 3.0.0-rc3-2-g0e96c45 (65) 202MB -
refreshed: 2017-12-26 07:31:30 +0200 SAST
channels:
  stable: 3.0.0-rc7 (116) 202MB -
  candidate: 3.0.0-rc7 (116) 202MB -
  beta: 3.0.0-rc7 (118) 202MB -
  edge: 4.0.0-dev-827-gcda6b57 (117) 201MB -

So I did a general snap refresh which did not seem to want to refresh the VLC snap:

$ sudo snap refresh
All snaps up to date.

That did not seem right, so I tried an explicit refresh of VLC which revealed that there were VLC related changes in progress.

mark@mark-X1Y2:~$ sudo snap refresh vlc
error: cannot refresh "vlc": snap "vlc" has changes in progress

And 'snap changes' confirmed that:

$ snap changes
ID Status Spawn Ready Summary
93 Doing 2018-01-20T06:01:54Z - Auto-refresh snaps "core", "vlc", "juju"
94 Done 2018-01-20T06:11:00Z 2018-01-20T06:11:00Z Refresh all snaps: no updates
95 Done 2018-01-20T06:11:29Z 2018-01-20T06:11:29Z Refresh all snaps: no updates

What would be better is if 'snap refresh' mentioned the in-progress changes, perhaps like this:

$ sudo snap refresh
core auto-refresh in progress
vlc auto-refresh in progress
juju auto-refresh in progress

Alternatively, perhaps this is another use case for the upcoming warnings capability?