fast-csv

Parsing CSV

This feature allows you to parse CSV files or strings. The code sample demonstrates how to read a CSV file using a stream, parse it with headers, and log each row to the console.

const fs = require('fs');
const fastcsv = require('fast-csv');

fs.createReadStream('data.csv')
  .pipe(fastcsv.parse({ headers: true }))
  .on('data', row => console.log(row))
  .on('end', () => console.log('CSV file successfully processed'));

Formatting Data to CSV

This feature allows you to format JavaScript data arrays or streams to CSV. The code sample shows how to take an array of objects and write it to a CSV file with headers.

const fs = require('fs');
const fastcsv = require('fast-csv');

const data = [{ id: 1, name: 'John Doe' }, { id: 2, name: 'Jane Doe' }];

fastcsv
  .write(data, { headers: true })
  .pipe(fs.createWriteStream('out.csv'))
  .on('finish', () => console.log('Write to out.csv successfully!'));

Transforming Data

This feature allows you to transform data during the parse or format process. The code sample demonstrates how to read a CSV file, transform each row by combining first and last names into a full name, and then write the transformed data to a new CSV file.

const fs = require('fs');
const fastcsv = require('fast-csv');

fs.createReadStream('data.csv')
  .pipe(fastcsv.parse({ headers: true }))
  .transform(row => ({ fullName: row.firstName + ' ' + row.lastName }))
  .pipe(fastcsv.format({ headers: true }))
  .pipe(fs.createWriteStream('out.csv'))
  .on('finish', () => console.log('Transformed file successfully written.'));