md5-file | return an md5sum of a given file | Hacking library

const http = require('http');
const fs = require('fs');
const md5File = require('md5-file');
const fileToDownload = "http://i3.ytimg.com/vi/J---aiyznGQ/mqdefault.jpg";
var counter = 0;

function request() {
    counter = counter + 1;
    console.log("downloading " + counter);
    const save = fs.createWriteStream("last_download.jpg");

    http.get(fileToDownload, function(response) {
        response.pipe(save);
        response.on('end',function () {
            save.end();

        })
    });


    save.on('finish',function () {

        const hash1 = md5File.sync('last_download.jpg');
        const hash2 = md5File.sync('last_unique.jpg');

        console.log(hash1,hash2);
        // it is a new file
        if (hash1.localeCompare(hash2) != 0) {
            console.log('Unique file spotted!');
            fs.copyFileSync('last_download.jpg','last_unique.jpg');
            fs.copyFileSync('last_unique.jpg','file' + counter + '.jpg');
        }

    });



}

setInterval(request, 3000);