How to deploy Flask-SocketIO on server? - flask

Question

I've made a project that using flask_socketio extension for user notifications and i want to deploy it on server .
I've already finished reading the Flask-SocketIO documentation and just did everything literally in Deployment section.
Now if i run the application at the beginning everything works fine, inside the console i've just logged a message if user logged in that says User Connected! just to make sure it work .
Now, i am logged in and the site works just fine, but if i want to navigate the other pages of the site it hangouts for a while lets say 30s and it logs me out .
Here is some code snippets:
base.html the base is extended for all pages
<script type="text/javascript">
var socket = io.connect('http://' + document.domain + ':' + location.port + '/notifications-{{session.get("client_logged_in")}}-{{session.get("client_family")}}');
var appointments_received = [];
socket.on('connect', function(){
console.log('User Connected!');
});
socket.on('new_message', function(msgChat){
$('<li class="notification">\
<div class="notification_client_ava_border">\
{% if '+msgChat.image+' %}\
<img src="/static/img/'+msgChat.image+'" alt="myproject" class="notification_client_ava">\
{% else %}\
<img src="/static/img/main.png" alt="myproject" class="notification_client_ava">\
{% endif %}\
</div>\
<div class="notification_info">\
<div class="client_info">\
<p class="user_name">\
You have new message from: '+msgChat.from+'\
'+shortName+'\
</p>\
</div>\
<br>\
<div class="service_info">\
{% if '+actionArray[0] == +' "Message:" %}\
<span>'+msgChat.message+'</span></br>\
{% endif %}\
</div>\
<br><br>\
<div class="">\
<span class="date">\
'+moment().fromNow()+'\
</span>\
</div>\
</div>\
<div class="notification_action">\
<a href="/user/cat-{{g.current_directory}}/chat/'+msgChat.to_url_+'?current_user={{session.get("client_logged_in")}}+{{session.get("client_family")}}" id="noty_read" class="btn btn-primary btn-block" data-get='+msgChat.noty_id+'>read it</a>\
</div>\
</li>'
).appendTo('ul#messages_list');
});
</script>
myapp.service here the Gunicorn instance to serve my project inside system directory
[Unit]
Description=Gunicorn
After=network.target
[Service]
User=gard
WorkingDirectory=/home/gard/myproject
Environment="PATH=/home/gard/myproject/venv/bin"
ExecStart=/home/gard/myproject/venv/bin/gunicorn --bind 0.0.0.0:5000 manage:app
[Install]
WantedBy=multi-user.target
Here is also my project config file the Nginx using to serve my project:
server {
listen 80;
server_name 123.45.678.901;
location / {
proxy_set_header X-Forward-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect off;
if (!-f $request_filename) {
proxy_pass http://127.0.0.1:5000;
break;
}
}
location /socket.io {
include proxy_params;
proxy_http_version 1.1;
proxy_buffering off;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "Upgrade";
proxy_pass http://127.0.0.1:5000/socket.io;
}
}
Here all my codes that i can provide and i repeat , the site work just fine and i can see the User Connected! message inside the console when user logs in my home page , but if i want to navigate another pages the hangs happens and it logs me out of site .
I forgot to show the error that i indeed up with inside the console :
http://123.45.678.901/socket.io/?EIO=3&transport=polling&t=LtFziAg&sid=636e939b538f4b0ca6df5cd521c2e187 400 (BAD REQUEST)

Answer 1

The problem is solved , i must define which async_mode to use inside the SocketIO structure .
Flask-SocketIO by default gives the first choice for Eventlet , the second choice goes to Gevent , for more information read this issues/294
To resolve this kind of problem just add this to your code :
socketio = SocketIO(async_mode='gevent')