Major Description
Aurora clientv2 commands currently support very flexible hooks which get used for a variety of purposes. One of the most popular usecases is as a safety-check mechanism: hooks can add extra safety checks to commands that mutate or kill aurora jobs.
Unfortunately, these hooks are clientv2 only. Once we've got users transitioned to clientv2, that will be fine, but for now, clientv1 is acting as a backdoor to allow users to bypass hooks.
Cluster administrators should have the ability to prevent this, by applying some kind of hooks to the aurora commands that mutate jobs. At the same time, we don't want to provide the same level of support for hooks that we have in v2, so the v1 hooks should be simpler and lighter-weight, since they're just a temporary stopgap.