How to make ir.attachment mandatory and raise error when creating new leave request?
We want to make sure that when an employee creating a new Leave Request on Leaves App, the attachment (document, pdf) should be selected/attached.
Attachment option activates once Leave Request is saved.
So before Leave is Confirm, we want to raise message "Please select attachment before confirm leave request."
How we can do it in Python in inherited class or some other recommended way?