floaty snapshot should warn users about how long it takes to get snapshot

[briancain]

Vmpooler works by generating a snapshot sha and queueing the host for taking a snapshot. Depending on the load of vmpooler, this could take quite a while to complete making it a little confusing to users trying to use that snapshot name right away. This should probably add something to the floaty snapshot command to warn users about potential wait times.

[tylerpace]

Does the vmpooler offer a way to pull out snapshots associated with a user's token?

I'm just thinking that if snapshots can take a while and you can't notify a user when their snapshot is ready, can floaty at least look up snapshots so a user can do something like:

1. Request a snapshot.
2. ?
3. List snapshots to see if they have their new snapshot available.

[briancain]

I think the only way you can know about a snapshot is to query the hostname. And unfortunately that snapshot won't exist until the work has been finished and the snapshot is taken. Otherwise its hostname and snapshot id is placed on a worker queue to be worked on at a later time :{ I don't think there's a way to see if it's on the queue through the api.

You can query about a tokens status from the pooler, but snapshots aren't associated with tokens :(

[tylerpace]

Yeah, I was playing around with snapshot and query after I wrote that comment and it looks like you're kind of limited by how vmpooler associates the snapshots with VM info.

[briancain]

I think it would make sense if vmpooler associated snapshots with tokens, and each token could potentially have some metadata associated with it relaying the status of that snapshot (i.e. taken vs pending), but I'm not sure how much work that would take to update vmpooler to do so.

[briancain]

@tylerpace - how do you feel about inserting some sort of pending key into the snapshot output? I could also just print a warning to stdout above the hash like:

$ floaty snapshot host
Snapshot pending. See `floaty query host` to determine when snapshot is valid.
... snapshot output ...

Not entirely sold on that wording, but something like that perhaps.

[tylerpace]

Yeah, I think that's a pretty reasonable way to signal that snapshots aren't instant and provides some help on how to check on your snapshot. I'd probably swap See for Use.