Function loadDataFile

packages/sanddance-explorer/src/dataLoader.ts:11–50

(dataFile: DataFile)

import { SandDance } from '@msrvida/sanddance-react';

export const loadDataFile = (dataFile: DataFile) => new Promise<DataContent>((resolve, reject) => {
    const vega = SandDance.VegaDeckGl.base.vega;
    const loader = vega.loader();

    function handleRawText(text: string) {
        let data: object[];
        try {
            data = vega.read(text, { type: dataFile.type, parse: {} });
        }
        catch (e) {
            reject(e);
        }
        if (data) {
            loadDataArray(data, dataFile.type).then(dc => {
                if (dataFile.snapshotsUrl) {
                    fetch(dataFile.snapshotsUrl)
                        .then(response => response.json())
                        .then(snapshots => {
                            dc.snapshots = snapshots;
                            resolve(dc);
                        })
                        .catch(reject);
                } else if (dataFile.snapshots) {
                    dc.snapshots = dataFile.snapshots;
                    resolve(dc);
                } else {
                    resolve(dc);
                }
            }).catch(reject);
        }
    }

    if (dataFile.dataUrl) {
        loader.load(dataFile.dataUrl).then(handleRawText).catch(reject);
    } else if (dataFile.rawText) {
        handleRawText(dataFile.rawText);
    } else {
        reject('dataFile object must have either dataUrl or rawText property set.');
    }
});

export const loadDataArray = (data: object[], type: DataFileType) => new Promise<DataContent>((resolve, reject) => {
    const parse = type === 'csv' || type === 'tsv';