Handling multiple query results in models.py

[Devdatta Kulkarni]

Currently in models.py, we are using the following pattern for returning query results:

filter_by_project(context, result).one()

When multiple values that match the query criteria are present in a table, above will throw MultipleResultsFound exception.

Currently we are not catching this exception in models.py.

As an example see:

https://review.openstack.org/#/c/154645/2

This bug is to track work that we should do to change models.py to catch and handle correct exceptions.

[James Li (james-li-3)]

An example code that needs this fix is here:

https://github.com/stackforge/solum/blob/master/solum/objects/sqlalchemy/image.py#L66