example.js

const fs = require('fs');
const { Client } = require('./index');
const readline = require('readline');
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

/* 
* Checking if we have information about some previous loggin
*/
const SESSION_FILE_PATH = './session.json';
let sessionCfg;
if (fs.existsSync(SESSION_FILE_PATH)) {
    sessionCfg = require(SESSION_FILE_PATH);
}

/* 
* This represent begginig of declaration, you can parse values to puppeter also
* can avoiding a new loggin sendind previous login data saved on ./session.json
*/
const client = new Client({ 
    puppeteer: { headless: false }, 
    session: sessionCfg 
});

/* 
* Calling initialization pipeline, will open headless and start project
*/
client.initialize();

/* 
* This important step is fired when during loggin you're forced to 
* an 2factor authentication, this wrapper will ask you for some token
* received over SMS or e-mail, over terminal, when you type press ENTER.
* Method based on: https://github.com/joaomirandasa/headless2FA
*/
client.on('authentication_2fa', ()=>{
    rl.question("[2Factor Bypass] - What is the token received over SMS/E-mail? ", (input) => {
        client.emit('authentication_answer',input);
    });
});

/* 
* If everything goes well, your loggin is processed and you can save 
* data on some file to future avoid new loggins
*/
client.on('authenticated', (session) => {
    console.log('[AUTHENTICATED]', session);
    fs.writeFile(SESSION_FILE_PATH, JSON.stringify(session), function (err) {
        if (err) {
            console.error(err);
        }
    });
});

/* 
* When you face something wrong over loggin and auth,  
* probabbly is time to set headless: false and check
* why your auth failed
*/
client.on('auth_failure', inform => {
   console.error('[AUTHENTICATION FAILURE]', inform);
});

/* 
* Claps! Your instance is running now  
*/
client.on('ready', () => {
    console.log('[READY]');
});

/* 
* When you receive some message this event will be fired
*/
client.on('message', async msg => {
    console.log('[MESSAGE RECEIVED]', msg);
});

/* 
* For some reason your instance is disconnected, firing this event
*/
client.on('disconnected', (reason) => {
    console.log('[DISCONNECTED]', reason);
});