PROPOSAL: stop recording 'executing update-status hook'

[Ian Booth]

On 22/05/17 18:23, roger peppe wrote:
> I think it's slightly unfortunate that update-status exists at all -
> it doesn't really need to,
> AFAICS, as a charm can always do the polling itself if needed; for example:
> 
>     while :; do
>          sleep 30
>          juju-run $UNIT 'status-set current-status "this is what is happening"'
>     done &
> 
> Or (better) use juju-run to set the status when the workload
> executable starts and exits, avoiding the need for polling at all.
>

It's not sufficient to just set the status when the workload starts and exits.
One example is a database which periodically goes offline for a short time for
maintenance. The workload executable itself should not have to know how to
communicate this to Juju. By the agent running update-status hook periodically,
it allows the charm itself to establish whether the database status should be
marked as "maintetance" for example. Using a hook provides a standard way all
charms can rely on to communicate workload status in a consistent way.