OVO vif_details not loading correctly from DB

[Kevin Benton]

The modify_fields_from_db method for the port binding OVO does not work correctly with 'vif_details'. The json parser falls apart when it encounters the empty details case, which is represented in our DB schema as an empty string ''.

    obj_fields = self._test_class.modify_fields_from_db(db_obj)
  File "neutron/objects/ports.py", line 66, in modify_fields_from_db
    fields['vif_details'] = jsonutils.loads(fields['vif_details'])
  File "/opt/stack/neutron/.tox/py27/local/lib/python2.7/site-packages/oslo_serialization/jsonutils.py", line 241, in loads
    return json.loads(encodeutils.safe_decode(s, encoding), **kwargs)
  File "/usr/lib/python2.7/json/__init__.py", line 339, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python2.7/json/decoder.py", line 364, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python2.7/json/decoder.py", line 382, in raw_decode
    raise ValueError("No JSON object could be decoded")
ValueError: No JSON object could be decoded
Ran 2 (-269) tests in 1.157s (-41.866s)

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/392960

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/392960
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=660946a921ce41b196533fe49d0df4e5a479eea0
Submitter: Jenkins
Branch: master

commit 660946a921ce41b196533fe49d0df4e5a479eea0
Author: Kevin Benton <email address hidden>
Date: Wed Nov 2 13:45:10 2016 -0700

    Fix modify_fields_from_db for vif_details empty str

    vif_details is represented as an empty string in our DB schema
    when it's not defined. The 'modify_fields_from_db' method was
    incorrectly attempting to feed this directly into the json decoder.

    Closes-Bug: #1638703
    Change-Id: I7b13fb30de71bb4dce4dbab4ffe430e1d0ef8f3a

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 10.0.0.0b1 development milestone.