parse_inline.vl.json

{
  "data": {
    "values": [
      {"date": "20010101", "close": "1"},
      {"date": "20010102", "close": "2"},
      {"date": "20010103", "close": "3"}
    ],
    "format": {
      "parse": {
        "date": "date:'%Y%m%d'"
      }
    }
  },
  "mark": "line",
  "encoding": {
    "x": {
      "field": "date",
      "type": "temporal"
    },
    "y": {
      "field": "close",
      "type": "quantitative"
    }
  }
}