How to override delete logic on Flask Admin?

Question

I have been searching on Google and StackOverflow about this. Basically, I want to try and override the delete function on Flask-Admin to not actually delete a record, but instead update a row of the object called 'deleted_by' and 'deleted_on'.

I have found a few questions on StackOverflow that explain how to change the logic on the save button by using on_model_change, but no one specific about the delete model logic. I have also not found any information regarding this on the documentation. Could anyone show me how should I handle this issue?

Thanks in advance!

Zealous

Answer 1

Override method delete_model in your view. Here is the default behaviour if you are using Sqlalchemy views, note the call to self.session.delete(model) in the try ... except block.

def delete_model(self, model):
    """
        Delete model.
        :param model:
            Model to delete
    """
    try:
        self.on_model_delete(model)
        self.session.flush()
        self.session.delete(model)
        self.session.commit()
    except Exception as ex:
        if not self.handle_view_exception(ex):
            flash(gettext('Failed to delete record. %(error)s', error=str(ex)), 'error')
            log.exception('Failed to delete record.')

        self.session.rollback()

        return False
    else:
        self.after_model_delete(model)

    return True

You would need something like the following in your view:

class MyModelView(ModelView):


   def delete_model(self, model):
        """
            Delete model.
            :param model:
                Model to delete
        """
        try:
            self.on_model_delete(model)
            # Add your custom logic here and don't forget to commit any changes e.g. 
            # self.session.commit()
        except Exception as ex:
            if not self.handle_view_exception(ex):
                flash(gettext('Failed to delete record. %(error)s', error=str(ex)), 'error')
                log.exception('Failed to delete record.')

            self.session.rollback()

            return False
        else:
            self.after_model_delete(model)

        return True

Also, you might not want to bother with the self.on_model_delete(model) and self.after_model_delete(model) calls because by default they do nothing.

Pollak