Comment 1 for bug 1533176

I am planning to fix this by making the check_resource from worker as a scheduler.wrappertask. The check_resource will also register an event before starting and after every step it will check the state of event. If the event is ready with a cancel message, the check_resource should stop. This is similar to how the existing stack-cancel-update works.

When the stack-cancel-update request is received, the cancel message is broad-casted to each engine worker and the registered events are sent cancel message. The next step() of check_resource should see this event message and bail out.