custom

Custom data processing logic that allows users to define their own operation methods.

custom is a transform in data.transform, not a connector replacing inline or fetch. Its callback receives the previous step’s data and returns the next step’s data. Do not assign the callback directly to an ordinary mark’s data.

Getting Started

const data = [
  { a: 1, b: 2, c: 3 },
  { a: 4, b: 5, c: 6 },
];

chart.options({
  type: 'view',
  data: {
    type: 'inline',
    value: data,
    transform: [
      {
        type: 'custom',
        callback: (data) => data.map((d) => ({ ...d, sum: d.a + d.b + d.c })),
      },
    ],
  },
});

Options