Add some warnings around virsh-cleanup

[cgwalters]

I actually had some other VMs; luckily in my case they're all
easy to recreate, but others may not be in the same situation.

[abhinavdahiya]

/assign @wking @yifan-gu

[wking]

[[ and =~ are Bash-isms. Can we use:

echo "Press control-C to abort, or enter to continue."
read

[cgwalters]

Can I just change it to /bin/bash instead?

[wking]

Can I just change it to /bin/bash instead?

The Control-C/enter approach seems usable enough to me that I don't think it's worth breaking POSIX compat. But most folks will have Bash, so I don't feel too strongly about it. And I'm not an approver anyway ;).

[wking]

An alternative to require an explicit Y/y in POSIX would be something like

printf 'Warning: This will destroy effectively all libvirt resources\nContinue [yN]? '
read CONTINUE
if test "${CONTINUE}" != y -a "${CONTINUE}" != Y
then
	echo 'Aborted' >&2
	exit 1
fi

[crawford]

@cgwalters I don't want to break POSIX compatibility since I depend on that to use these scripts. If it has to be bash, you need to use #!/usr/bin/env bash, but I like @wking's first suggestion better.

[cgwalters]

OK, done with @wking 's suggestion ⬇️

[wking]

/lgtm

[crawford]

/lgtm

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cgwalters, crawford, wking

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [crawford]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[wking]

The e2e-aws error was:

Waiting for router to be created ...
NAME                           STATUS    ROLES     AGE       VERSION
ip-10-0-141-50.ec2.internal    Ready     etcd      3m        v1.11.0+d4cacc0
ip-10-0-158-123.ec2.internal   Ready     etcd      3m        v1.11.0+d4cacc0
ip-10-0-162-74.ec2.internal    Ready     etcd      3m        v1.11.0+d4cacc0
ip-10-0-79-80.ec2.internal     Ready     master    3m        v1.11.0+d4cacc0
NAME      DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
router    1         1         1            0           2s
error: timed out waiting for the condition
2018/08/01 18:15:41 Container setup in pod e2e-aws failed, exit code 1, reason Error
Another process exited

which is obviously unreleated to this change to an untested script.

/retest

[wking]

This time the e2e-aws error was:

1 error(s) occurred:

* module.vpc.output.etcd_sg_id: Resource 'aws_security_group.etcd' does not have attribute 'id' for variable 'aws_security_group.etcd.*.id'

Dunno why e2e-aws has been so flaky recently...

/retest