Could not get stack_id during healing a scale outed vnf instance

[LiangLu]

get this error message during running heal api for a scaleout-ed vnfinstance:

Error: Heal Vnf failed for vnf e0a29dc3-7ad1-4a06-a9bd-52a54b1591d1, error: Failed to find stack_id None
 ^[[00m: tacker.common.exceptions.VnfHealFailed: Heal Vnf failed for vnf e0a29dc3-7ad1-4a06-a9bd-52a54b1591d1, error: Failed to find stack_id None

This error message is caused by empty stack_id value in vnfc_res_info.metadata,
and in an instantiated vnfinstance, there is value in vnfc_res_info.metadata.

In instantaite_vnf, vnfc_res_info.metadata is get from tacker variable stack_resources
https://opendev.org/openstack/tacker/src/branch/master/tacker/vnfm/infra_drivers/openstack/openstack.py#L1016

However in scale_out, this variable is get from heat_client:
https://opendev.org/openstack/tacker/src/branch/master/tacker/vnfm/infra_drivers/openstack/openstack.py#L1380

In our environment, heat does not save resource_id into metadata, thus, scale_out cannot get right resource.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/tacker 5.0.0.0rc1 release candidate.

[Yasufumi Ogawa (yasufum)]

Fixed: https://review.opendev.org/c/openstack/tacker/+/781183