writefile in node js
// write_stream.js
const fs = require('fs');
let writeStream = fs.createWriteStream('secret.txt');
// write some data with a base64 encoding
writeStream.write('aef35ghhjdk74hja83ksnfjk888sfsf', 'base64');
// the finish event is emitted when all data has been flushed from the stream
writeStream.on('finish', () => {
console.log('wrote all data to file');
});
// close the stream
writeStream.end();