index.js

'use strict';
const request = require('request');
// Imports dependencies and set up http server
const
    express = require('express'),
    bodyParser = require('body-parser'),
    app = express().use(bodyParser.json()); // creates express http server

// Sets server port and logs message on success
app.listen(process.env.PORT || 1337, () => console.log('webhook is listening'));
app.use(express.static('public'));
// Creates the endpoint for our webhook 
app.post('/webhook', (req, res) => {

    let body = req.body;

    // Checks this is an event from a page subscription
    if (body.object === 'page') {

        // Iterates over each entry - there may be multiple if batched
        body.entry.forEach(function (entry) {

            // Gets the body of the webhook event
            let webhook_event = entry.messaging[0];
            console.log(webhook_event);


            // Get the sender PSID
            let sender_psid = webhook_event.sender.id;
            console.log('Sender PSID: ' + sender_psid);

            // Check if the event is a message or postback and
            // pass the event to the appropriate handler function
            if (webhook_event.message) {
                handleMessage(sender_psid, webhook_event.message);
            } else if (webhook_event.postback) {
                handlePostback(sender_psid, webhook_event.postback);
            }

        });

        // Returns a '200 OK' response to all requests
        res.status(200).send('EVENT_RECEIVED');
    } else {
        // Returns a '404 Not Found' if event is not from a page subscription
        res.sendStatus(404);
    }

});

// Adds support for GET requests to our webhook
app.get('/webhook', (req, res) => {

    // Your verify token. Should be a random string.
    let VERIFY_TOKEN = "8f200c9fba24d4d4632d1e87cfffd434"

    // Parse the query params
    let mode = req.query['hub.mode'];
    let token = req.query['hub.verify_token'];
    let challenge = req.query['hub.challenge'];

    // Checks if a token and mode is in the query string of the request
    if (mode && token) {

        // Checks the mode and token sent is correct
        if (mode === 'subscribe' && token === VERIFY_TOKEN) {

            // Responds with the challenge token from the request
            console.log('WEBHOOK_VERIFIED');
            res.status(200).send(challenge);

        } else {
            // Responds with '403 Forbidden' if verify tokens do not match
            res.sendStatus(403);
        }
    }
});

// Handles messages events
function handleMessage(sender_psid, received_message) {
    let response;

    // Checks if the message contains text
    if (received_message.text) {
        // Create the payload for a basic text message, which
        // will be added to the body of our request to the Send API
        response = {
            "attachment": {
                "type": "template",
                "payload": {
                    "template_type": "list",
                    "top_element_style": "compact",
                    "elements": [
                        {
                            "title": "FELIPE",
                            "subtitle": "GEROLOMO",
                        },
                        {
                            "title": "VICTOR",
                            "subtitle": "GEROLOMO",
                        },
                        {
                            "title": "AEPS",
                            "subtitle": "WEBVIEW",
                            "buttons": [
                                {
                                    "type": "web_url",
                                    "url": "https://hidden-plateau-57043.herokuapp.com/aeps",
                                    "title": "Visit Google",
                                    "webview_height_ratio": "tall",
                                    "messenger_extensions": true
                                },

                            ]
                        },
                    ]
                }
            }
        }

    } else if (received_message.attachments) {
        // Get the URL of the message attachment
        let attachment_url = received_message.attachments[0].payload.url;
        response = {
            "attachment": {
                "type": "template",
                "payload": {
                    "template_type": "generic",
                    "elements": [{
                        "title": "Is this the right picture?",
                        "subtitle": "Tap a button to answer.",
                        "image_url": attachment_url,
                        "buttons": [
                            {
                                "type": "postback",
                                "title": "Yes!",
                                "payload": "yes",
                            },
                            {
                                "type": "postback",
                                "title": "No!",
                                "payload": "no",
                            }
                        ],
                    }]
                }
            }
        }
    }

    // Send the response message
    callSendAPI(sender_psid, response);
}
// Handles messaging_postbacks events
function handlePostback(sender_psid, received_postback) {
    let response;

    // Get the payload for the postback
    let payload = received_postback.payload;

    // Set the response based on the postback payload
    if (payload === 'yes') {
        response = { "text": "Thanks!" }
    } else if (payload === 'no') {
        response = { "text": "Oops, try sending another image." }
    }
    // Send the message to acknowledge the postback
    callSendAPI(sender_psid, response);
}
// Sends response messages via the Send API
function callSendAPI(sender_psid, response) {
    // Construct the message body
    let request_body = {
        "recipient": {
            "id": sender_psid
        },
        "message": response
    }

    console.log("MEnsagem: ", request_body);

    // Send the HTTP request to the Messenger Platform
    request({
        "uri": "https://graph.facebook.com/v2.6/me/messages",
        "qs": { "access_token": "EAAFbvdkTpjcBAAdDh6iTviG5BccPuZCyjQnTiRKGDtWP8IIcawZC02IiKzBBaMllkVjmhbsBQuPEDpq3Pmyxypl7zKZACN3i4kVXTsXQIBiLVMi1EiqR33jicJdl8vKjGtmt9hTYz7ZAepElNJZAAz075ZBw93Uol6oEZCG3W3ZCHKQlp6yP7IqF" },
        "method": "POST",
        "json": request_body
    }, (err, res, body) => {
        if (!err) {
            console.log('message sent!')
        } else {
            console.error("Unable to send message:" + err);
        }
    });
}

app.get('/index', (req, res, next) => {
    res.sendFile('public/index.html', {root: __dirname});
});