Heroku node.js and Flask application working locally but not in server

I have a web application which uses node.js and communicates with a Flask application to retrieve some configurations and send jobs to the back-end. The Flask returns a JSON with the information

Flask file (REST.PY):

from flask import Flask, jsonify, request, redirect, url_for
import subprocess

import os
import json
from cross_domain import *
app = Flask(__name__)

...

@app.route('/api/v1.0/proteins', methods=['GET', 'OPTIONS'])
@crossdomain(origin='*')
def get_protein_names():
proteins = os.walk(TARGET).next()[1]
protein_lst = [{"filename": protein} for protein in sorted(proteins) if  protein != "scripts"]
return jsonify({"files": protein_lst})

if __name__ == '__main__':
app.run(debug=True,port=9000)

and here is the js code:

...

this.restAddr = "http://127.0.0.1:9000";

...

this.httpGet = function(url, callback) {
var xmlHttp;
xmlHttp = new XMLHttpRequest();
xmlHttp.onreadystatechange = function() {
  if (xmlHttp.readyState === 4 && xmlHttp.status === 200) {
    callback(xmlHttp.responseText);
  }
};

...

httpGet(restAddr + "/api/v1.0/proteins", populateProteins);

I'm currently using this buildback in order to run both commands in the Procfile. It works when I run locally with foreman start, but when I deploy to Heroku the frameworks doesn't communicate with each other anymore and there is no response in the XMLHTTPRequests. I can still work with the node.js part, though.

Here is the Heroku logs:

...
2016-06-16T20:08:59.174025+00:00 app[web.1]: buildpack=runit ps=python at=start
2016-06-16T20:08:59.174156+00:00 app[web.1]: buildpack=runit ps=node at=start
2016-06-16T20:09:04.490687+00:00 app[web.1]:  * Running on http://127.0.0.1:9000/ (Press CTRL+C to quit)
2016-06-16T20:09:04.515389+00:00 app[web.1]:  * Restarting with stat
2016-06-16T20:09:05.138990+00:00 heroku[web.1]: State changed from starting to up
2016-06-16T20:09:05.568687+00:00 app[web.1]:  * Debugger is active!
2016-06-16T20:09:05.593316+00:00 app[web.1]:  * Debugger pin code: 237-920-039
2016-06-16T20:09:06.730693+00:00 app[web.1]: Succeeded connected to: <MONGODB_URI> in port 35556

Here is what appears when running Foreman:

 $ foreman start -f Procfile.local 
14:59:30 node.1   | started with pid 21241
14:59:30 python.1 | started with pid 21242
14:59:31 python.1 |  * Running on http://127.0.0.1:9000/ (Press CTRL+C to quit)
14:59:31 python.1 |  * Restarting with stat
14:59:31 python.1 |  * Debugger is active!
14:59:31 python.1 |  * Debugger pin code: 215-168-436
14:59:31 node.1   | Succeeded connected to: mongodb://localhost/algdock in port 3000

I need an insight about why is not working when it's deployed or if there is some another better approach to this problem.

EDIT: using gunicorn for python it gives the Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch

Procfile.web

web: node gui/web_app/AlGDock/bin/www
web: gunicorn --pythonpath gui/api --bind 127.0.0.1:9000 wsgi:app

wsgi.py

from REST import app
if __name__ == "__main__":
    app.run()

Heroku Logs:

2016-06-17T00:35:25.808594+00:00 heroku[web.1]: Starting process with command `bin/runsvdir-dyno`
2016-06-17T00:35:26.398041+00:00 heroku[web.1]: Process exited with status 0
2016-06-17T00:35:28.003708+00:00 app[web.1]: buildpack=runit ps=web at=start
2016-06-17T00:35:28.376799+00:00 app[web.1]: [2016-06-17 00:35:28 +0000] [15] [INFO] Starting gunicorn 19.6.0
2016-06-17T00:35:28.377454+00:00 app[web.1]: [2016-06-17 00:35:28 +0000] [15] [INFO] Listening at: http://127.0.0.1:9000 (15)
2016-06-17T00:35:28.377583+00:00 app[web.1]: [2016-06-17 00:35:28 +0000] [15] [INFO] Using worker: sync
2016-06-17T00:35:28.385995+00:00 app[web.1]: [2016-06-17 00:35:28 +0000] [20] [INFO] Booting worker with pid: 20
2016-06-17T00:35:28.826322+00:00 app[web.1]: /app/target/
2016-06-17T00:35:28.826340+00:00 app[web.1]: /app/AlGDock/
2016-06-17T00:36:25.826633+00:00 heroku[web.1]: Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch