index.js

var fs = require('fs');
var exec = require('child_process').execSync;

var API_KEY = 'XXXXXXXXXXXX'; // your url2png APIKEY
var PRIVATE_KEY = 'XXXXXXXXXXXX'; // your url2png SECRET

var url2png = require('url2png')(API_KEY, PRIVATE_KEY);

var dest = fs.statSync('/tmp/message.txt').isFile();
if (!dest) fs.writeFileSync('/tmp/message.txt');

var options = {
    viewport: '940x580',
    thumbnail_max_width : 940,
    protocol: 'https',
    delay: 10,
    unique: Date.now(),
    ttl: 60 * 60 * 24 * 2
};

var time = exec('date +%Y-%m-%d_%H-%M');
var image_name = 'wag'; // name your file
var img_file = image_name + '_' + time + '.png';
img_file = img_file.replace(/[\s\?]/gm,'');

var url = 'google.com'; // the url you wish to have screenshotted and emailed to you
var recipient = 'name@example.org'; // email to recieve the picture
var subject = "Subject Line"; // Subject line, be careful to escape quotes


var stream = url2png.readURL(url, options).pipe(fs.createWriteStream(img_file));

stream.on('finish', function() {
    exec('mutt -a ' + img_file + ' -s "' + subject + '" -- ' + recipient + ' < /tmp/message.txt');
    exec('rm '+ img_file);
});