test.js

const csv = require('csvtojson')
const fs = require('fs')

// this no worky
function dosomething(data) {
  console.log(data)
}
async function main() {

  var mappingData = await parseCSV("map.csv", ",")

  const fileStream = fs.createReadStream("src.csv")
  const writeFile = fs.createWriteStream('output.csv')
  // read the csv => do some work => write the final thing back out to another csv file
  fileStream.pipe(csv()).pipe(dosomethings()).pipe(writeFile)

}
main()