index.js

var fs = require('fs');
var tldjs = require('tldjs');

var disposable = fs.readFileSync(__dirname + '/data/disposable.txt').toString().split('\n');
var free = fs.readFileSync(__dirname + '/data/free.txt').toString().split('\n').concat(disposable);

function isFree(email) {
    if (typeof email !== 'string') throw new TypeError('email must be a string');
    console.log(email);
    var domain = tldjs.getDomain(email.split('@').pop());
    console.log(domain, free.indexOf(domain));
    return free.indexOf(domain) !== -1;
}

function isDisposable(email) {
    if (typeof email !== 'string') throw new TypeError('email must be a string');
    var domain = tldjs.getDomain(email.split('@').pop());
    return disposable.indexOf(domain) !== -1;
}

module.exports = {
    isFree: isFree,
    isDisposible: isDisposable
};