grafana/packages/grafana-data/src/dataframe/StreamingDataFrame.test.ts

import { FieldType } from '../types/dataFrame';
import { DataFrameJSON } from './DataFrameJSON';
import { StreamingDataFrame } from './StreamingDataFrame';

describe('Streaming JSON', () => {
  describe('when called with a DataFrame', () => {
    it('should decode values not supported natively in JSON (e.g. NaN, Infinity)', () => {
      const json: DataFrameJSON = {
        schema: {
          fields: [
            { name: 'time', type: FieldType.time },
            { name: 'name', type: FieldType.string },
            { name: 'value', type: FieldType.number },
          ],
        },
        data: {
          values: [
            [100, 200, 300],
            ['a', 'b', 'c'],
            [1, 2, 3],
          ],
        },
      };

      const stream = new StreamingDataFrame(json);
      expect(stream.fields.map((f) => ({ name: f.name, value: f.values.buffer }))).toMatchInlineSnapshot(`
        Array [
          Object {
            "name": "time",
            "value": Array [
              100,
              200,
              300,
            ],
          },
          Object {
            "name": "name",
            "value": Array [
              "a",
              "b",
              "c",
            ],
          },
          Object {
            "name": "value",
            "value": Array [
              1,
              2,
              3,
            ],
          },
        ]
      `);

      stream.update({
        data: {
          values: [[400], ['d'], [4]],
        },
      });

      expect(stream.fields.map((f) => ({ name: f.name, value: f.values.buffer }))).toMatchInlineSnapshot(`
        Array [
          Object {
            "name": "time",
            "value": Array [
              100,
              200,
              300,
              400,
            ],
          },
          Object {
            "name": "name",
            "value": Array [
              "a",
              "b",
              "c",
              "d",
            ],
          },
          Object {
            "name": "value",
            "value": Array [
              1,
              2,
              3,
              4,
            ],
          },
        ]
      `);
    });
  });
});