Supervisor + Nginx + Python3 deploy Tornado

Supervisor deployment tornado

#1 surroundings##

CentOS 7.6
Python3.7

#2 demand analysis##

• Tornado is different from other Python web frameworks, it comes with HTTPServer
• Tornado does not need a uWSGI startup like Django
• Tornado can be started with uWSGI, but its performance will be greatly affected because uWSGI is a synchronous web server

Therefore, this article mainly introduces the use of Supervisor + Nginx to deploy a simple Tornado application

#3 Overall division of labor##

• Supervisor

Used to start/close Tornado application management

• Nginx

Reverse proxy + Load Balancing

#4 Supervisor

#4.1 Install Supervisor on CentOS

There are two installation methods:

• Install using yum

yum install -y supervisor

• Install using pip

pip3 install supervisor

This article uses pip3 to install

This method of installation will not automatically generate configuration files, you need to manually create configuration folders and configuration files

Manually generate node files:

mkdir -p /etc/supervisor/conf.d 

Manually generate the configuration file:

echo_supervisord_conf >/etc/supervisor/supervisord.conf

#4.2 Explain the role of the two files###

• supervisord.conf

Supervisor configuration file, we only need to care about the last part of the file

......[ include]
files =/etc/supervisor/conf.d/*.conf

This means that by adding the *.conf file under /etc/supervisor/conf.d/, we only need to add the node file in /etc/supervisor/conf.d/ (similar to Nginx configuration files)

• conf.d

Add folder

#4.3 Node configuration file###

[ group:tornadoes]
programs=tornado-9898,tornado-9899[program:tornado-9898]
command=python3 /root/a.py --port=9898
directory=/root
user=root
autorestart=true
redirect_stderr=true
stdout_logfile=/root/tornado1.log
loglevel=info                                                                                
[ program:tornado-9899]
command=python3 /root/a.py --port=9899
directory=/root
user=root
autorestart=true
redirect_stderr=true
stdout_logfile=/root/tornado2.log
loglevel=info   

Explanation:

• command

python3 /root/a.py --port=9898

The command that needs to be executed, python3 can be replaced with the absolute path of the python interpreter, /root/a.py is my Tornado file path

#4.4 tornado application###

import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web
import tornado.httpclient
from tornado.options import define, options

define("port",default=8765, help="run on the given port ", type=int)classExampleHandler(tornado.web.RequestHandler):                                            
 def get(self):
  self.write({"status":1,"msg":"success"})if __name__=="__main__":

 tornado.options.parse_command_line()
 app = tornado.web.Application(handlers=[(r"/", ExampleHandler)])
 http_server = tornado.httpserver.HTTPServer(app)
 http_server.listen(options.port)
 tornado.ioloop.IOLoop.instance().start()

#4.5 operating###

• Start Supervisor

supervisord -c /etc/supervisor/supervisord.conf

• Shut down Supervisor

ps -ef | grep supervisord
kill -s SIGTERM pid

#4.6 Management Supervisor

• Enter the client

supervisorctl

• Stop a server process

supervisor> stop tornadoes:tornado-9898

• Check status

supervisor> status

• Stop running the entire tornado server process group

supervisor> stop tornadoes:

• Start a process

supervisorctl start program_name

• Restart a process

supervisorctl restart program_name

• End all processes belonging to the group named groupworker

supervisorctl stop groupworker:

• Stop all processes

supervisorctl stop all

• Load the latest configuration file, stop the original process and start and manage all processes according to the new configuration

supervisorctl reload

• Start a new configuration or changed process

supervisorctl update

#5 Nginx

upstream tornados{
 server 127.0.0.1:9898;
 server 127.0.0.1:9899;}
proxy_next_upstream error;
server {
 listen 9999;
 server_name www.minhung.me;
 location /{
  proxy_pass_header Server;
  proxy_set_header Host $http_host;
  proxy_redirect off;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_pass http://tornados; #Pass the request direction proxy to tornado server, load balance
    }}