blockdevice 2.0 schema check failed: model: expected string, got nothing

[Martin Packman]

With bug 1575808 fixed, MAAS 2.0 in CI now bootstraps, but fails when deploying due to another schema check issue on maas block-device output:

machines:
  "0":
    juju-status:
      current: error
      message: 'cannot run instances: cannot run instance: blockdevice 2: blockdevice
        2.0 schema check failed: model: expected string, got nothing'
      since: 28 Apr 2016 17:14:49Z
    instance-id: pending
    machine-status:
      current: pending
      since: 28 Apr 2016 17:14:46Z
    series: xenial

Going by the same paste output from before, it seems several fields can be null for virtual devices:

<http://paste.ubuntu.com/16085749/>

    {
        "size": 21470642176,
        "block_size": 4096,
        "used_size": 21470642176,
        "tags": [],
        "filesystem": {
            "uuid": "ac5c61b8-84bb-4b10-b399-466570bae392",
            "mount_point": "/",
            "label": "root",
            "mount_options": null,
            "fstype": "ext4"
        },
        "type": "virtual",
        "resource_uri": "/MAAS/api/2.0/nodes/node-ce3fd804-71e4-11e5-80fe-525400c43ce5/blockdevices/3/",
        "model": null,
        "serial": null,
        "id_path": null,
        "partitions": [],
        "partition_table_type": null,
        "id": 3,
        "available_size": 0,
        "name": "vgroot-lvroot",
        "path": "/dev/disk/by-dname/lvroot",
        "used_for": "ext4 formatted filesystem mounted at /",
        "uuid": "b61d5b69-e893-4612-be0d-9370dcd7f287"
    }

[Christian Muirhead (2-xtian)]

Fixed in gomaasapi - https://github.com/juju/gomaasapi/pull/52
Updating the dependency in juju now.

[Christian Muirhead (2-xtian)]

Building now: https://github.com/juju/juju/pull/5316

[Christian Muirhead (2-xtian)]

I've asked the MAAS team to look through our schema to tell us other fields that are optional or nullable in the hope of fixing these missing field errors all at once.