trunk_details missing sub port MAC addresses for LIST

[Matthew Booth]

When returning port details, trunk_details.sub_ports should contain:
* segmentation_id
* segmentation_type
* port_id
* mac_address

This is the case when GETting a single port, but when listing ports mac_address is missing.

In the following:
* Parent port: a47df912-1cba-458c-9bb9-00cd3d71b9e6
* Trunk: 70f314f8-5577-4b98-be9c-68bbe3791d7f
* Sub port: d11793a9-8862-4378-a1fe-045f04dad841

GET request:

> curl -s -H "X-Auth-Token: $OS_TOKEN" "https://rhos-d.infra.prod.upshift.rdu2.redhat.com:13696/v2.0/ports/a47df912-1cba-458c-9bb9-00cd3d71b9e6" | jq
{
  "port": {
    ...
    "trunk_details": {
      "trunk_id": "70f314f8-5577-4b98-be9c-68bbe3791d7f",
      "sub_ports": [
        {
          "segmentation_id": 100,
          "segmentation_type": "vlan",
          "port_id": "d11793a9-8862-4378-a1fe-045f04dad841",
          "mac_address": "fa:16:3e:88:29:a0"
        }
      ]
    },
    ...
  }
}

LIST request returning the same port:

> curl -s -H "X-Auth-Token: $OS_TOKEN" "https://rhos-d.infra.prod.upshift.rdu2.redhat.com:13696/v2.0/ports?id=a47df912-1cba-458c-9bb9-00cd3d71b9e6" | jq
{
  "ports": [
    {
      ...
      "trunk_details": {
        "trunk_id": "70f314f8-5577-4b98-be9c-68bbe3791d7f",
        "sub_ports": [
          {
            "segmentation_id": 100,
            "segmentation_type": "vlan",
            "port_id": "d11793a9-8862-4378-a1fe-045f04dad841"
          }
        ]
      },
      ...
    }
  }
}

Note that mac_address is missing for the LIST request.

* Version: Little bit of guesswork going on here, but Nova reports a latest microversion of 2.79, which corresponds to Train.

[Mamatisa Nurmatov (isabek)]

Checked on Train environment and confirmed

[yatin (yatinkarel)]

@mbooth thanks for the bug report. So i checked and the behavior is intentionally to optimize the requests as part of [1], see the commits [2].

Can you also share more context on if this is causing some issue on nova side or it was just an observation?

[1] https://bugs.launchpad.net/neutron/+bug/1905268
[2] https://review.opendev.org/q/Ic08e4049f6156c0700ca3c7aee251b6eb0eb97da

[Rodolfo Alonso (rodolfo-alonso-hernandez)]

Hi @mbooth:

As Yatin commented, that was intentionally optimized to avoid the subport query. If needed, you can propose to have an additional parameter in the list command (if that is something acceptable in the CLI project) and you can create an extension to the trunk details API request, adding this extra info. Of course, this API call will be much slower.

I would mark this bug as a RFE.

Regards.

[Matthew Booth (mbooth-9)]

No, this is fine. It was just unexpected as the difference is not documented. Documenting that this is deliberate would be just as good.