flask + nginx + uwsgi + flask

現象

flask + nginx + uwsgi + flask_socketioを用いてチャットアプリを作ろうと思っているのですが
socketをうまく繋げません

エラー

ソケットに繋ぐ画面に行くとコンソールログに以下のエラーが出てきます

socket.io.min.js:1 GET http://localhost:8888/socket.io/?EIO=3&transport=polling&t=xxxxxx 502 (Bad Gateway)

各設定ファイル

Nginx

server {
  listen 8888;
  server_name localhost;
  location / {
    include uwsgi_params;
    uwsgi_pass unix:///tmp/uwsgi.sock;
  }

  location /socket.io/ {
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
    proxy_pass http://unix:///tmp/uwsgi.sock;
  }
}

uWSGI

[uwsgi]
chdir = /root/chat
module = app
callable = app
master = true
processes = 5
socket = /tmp/uwsgi.sock
buffer-size=32768
chmod-socket = 666
die-on-term = true
http-websockets = true
touch-reload = /tmp/reload.triger
vacum = true

index.html(一部抜粋)

javascript
1<script type="text/javascript" src="//cdnjs.cloudflare.com/ajax/libs/socket.io/1.3.5/socket.io.min.js"></script>
2<script type="text/javascript" charset="utf-8">
3    $(document).ready(function() {
4        namespace = '/test';
5        console.log(location.protocol + '//' + document.domain + ':' + location.port + namespace);
6        var socket = io.connect(location.protocol + '//' + document.domain + ':' + location.port + namespace);
7        socket.on('connect', function() {
8            socket.emit('my_event', {data: 'I\'m connected!'});
9        });
10</script>

app.py(一部抜粋)

python
1#!/usr/bin/env python
2from threading import Lock
3from flask import Flask, render_template, session, request
4from flask_socketio import SocketIO, emit, join_room, leave_room, \
5    close_room, rooms, disconnect
6
7@socketio.on('connect', namespace='/test')
8def test_connect():
9    global thread
10    with thread_lock:
11        if thread is None:
12            thread = socketio.start_background_task(target=background_thread)
13    emit('my_response', {'data': 'Connected', 'count': 0})
14
15
16if __name__ == '__main__':
17    socketio.run(app, debug=True)