[
  {
    "bases": [
      "DefaultParent"
    ],
    "fields": [
      "before",
      "value",
      "after"
    ]
  },
  {
    "payload": {},
    "source": {
      "errors": [
        "missing"
      ]
    },
    "generated": {
      "errors": [
        "missing"
      ]
    }
  },
  {
    "payload": {
      "value": 8
    },
    "source": {
      "before": 10,
      "value": 8,
      "after": 30
    },
    "generated": {
      "before": 10,
      "value": 8,
      "after": 30
    }
  }
]