Is there a standard way of setting up callbacks of actions to execute when a long-running operation finishes?

[jgeewax]

Referring to http://gcloud-python-bigtable.readthedocs.org/en/data-api-complete/cluster-api.html#check-on-current-operation

[dhermes]

So I previously had some code which would sleep (and the system test currently does).

However, empirically they only are on cluster operations and last for 0.5-1.0 seconds on average (see #2). Since these events/modifications are rare (and quick), I didn't think it was wise to build a lot of code to serve this purpose.

[dhermes]

/cc @tseaver