Discussion on: Parsing CSV Files in Node.js with fs.createReadStream() and csv-parser

[Jhony Rodrigues]

Hi. I came across this situation in an academic project and we had to use the traditional Promise() constructor.
csv-parser does not support promises natively. Same for FS stream and console.log methods
Your code would be more or less like this, trying as hard as possible to make it look like it.

function loadTransactions(): Promise<CsvTransactions[]> {
  const transactions: Promise<CsvTransactions[]> = new Promise((resolve, reject) => {
      const transactionsArray: CsvTransactions[] = []

      fs.createReadStream(csvFilePath, 'utf8')
        .pipe(csv())
        .on('data', row => {
          const { title, type, value, category }: CsvTransactions = row;
          console.log(row);
          transactionsArray.push({ title, type, value, category });
          console.log('transactionsArray inside loop: ', transactionsArray);
        })
        .on('end', () => {
          console.log('Csv file successfully processed!');
          resolve(transactionsArray)
        })
        .on('error', (err) => {
          reject(err)
        })
    }
  )

  console.log('transactionsArray outside loop: ', transactions);

  return transactions;
}

I'll take the opportunity and thank the author for the post that clarified other things for me.
Thank you!