definma-api/src/helpers/csv.ts

import {parseAsync} from 'json2csv';
import flatten from './flatten';

export default function csv(input: any[], f: (err, data) => void) {
  parseAsync(input.map(e => flatten(e)), {includeEmptyRows: true})
    .then(csv => f(null, csv))
    .catch(err => f(err, null));
}