Coding and decoding a file in base64 (for example a pdf file)

code_base64_decode.js

var fs = require('fs');
// Reade file synchronously and put the result in buffer
var file = fs.readFileSync('fileName.pdf');
// Code the file in base64
var base64EncodedPDF = new Buffer(file).toString('base64');
// Decode the file
var baseDecodedPDF = new Buffer(base64EncodedPDF, 'base64');
// Get the decoded file in its original format
fs.writeFileSync('decodedPDF.pdf', baseDecodedPDF);