Unhandled error when trying to delete wf that has triggers

[Anastasia Kuznetsova]

Steps to reproduce:
1. Create a simple wf
2. Create cron-trigger for this wf
3. Try to delete wf

Expected result:
Information message that we can't delete wf that has triggers and firstly user need to delete all triggers associated with it wf

Observed result:
mistral workflow-delete wf
(IntegrityError) (1451, 'Cannot delete or update a parent row: a foreign key constraint fails (`mistral`.`cron_triggers_v2`, CONSTRAINT `cron_triggers_v2_ibfk_1` FOREIGN KEY (`workflow_id`) REFERENCES `workflows_v2` (`id`))') 'DELETE FROM workflows_v2 WHERE workflows_v2.id = %s' ('7c95e1d3-6c07-4ac8-bdb3-edfb6ce9ec18',)

[Renat Akhmerov (rakhmerov)]

Need to think about other similar situations. For example, workbook -> workflows/actions relationship. The most preferred way is probably to warn the user about removing several objects and suggesting to pass an additional option, say -f (forced).

[Hardik Parekh (hardik-parekh047)]

Fix is committed to
https://review.openstack.org/#/c/231993/

[Anastasia Kuznetsova (akuznetsova)]

Bug was fixed more than a year ago, thus bug is going to be moved to Fix Released.