index.js

/**
 * Copyright 2016-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the license found in the
 * LICENSE file in the root directory of this source tree.
 */

var bodyParser = require("body-parser");
var express = require("express");
var app = express();
var xhub = require("express-x-hub");

app.set("port", process.env.PORT || 5000);
app.listen(app.get("port"));

app.use(xhub({ algorithm: "sha256", secret: process.env.APP_SECRET }));
app.use(bodyParser.json());

var token = process.env.TOKEN || "token";
var received_updates = [];

app.get("/", function (req, res) {
  console.log(req.query);
  res.send("<pre>" + JSON.stringify(received_updates, null, 2) + "</pre>");
});

app.get(["/facebook", "/instagram"], function (req, res) {
  if (req.query["hub.mode"] == "subscribe" && req.query["hub.verify_token"] == token) {
    res.send(req.query["hub.challenge"]);
  } else {
    res.sendStatus(400);
  }
});

app.post("/facebook", function (req, res) {
  console.log("Facebook request body:", req.body);

  // Process the Facebook updates here
  received_updates.unshift(req.body);
  res.sendStatus(200);
  return;

  if (!req.isXHubValid()) {
    console.log("Warning - request header X-Hub-Signature not present or invalid");
    res.sendStatus(401);
    return;
  }

  console.log("request header X-Hub-Signature validated");
});

app.post("/instagram", function (req, res) {
  console.log("Instagram request body:");
  console.log(req.body);
  // Process the Instagram updates here
  received_updates.unshift(req.body);
  res.sendStatus(200);
});

app.listen();