A cheat-sheet on how to run a flask application within gunicorn as a wsgi-server under the systemd control and integrate it with nginx.
Create a virtual environment. Prerequisite (ubuntu):
apt install python3-venv
Installation of gunicorn and flask:
mkdir <application_dir>
cd <application_dir>/
python3 -m venv .
. ./bin/activate
pip install gunicorn
pip install flask
Create an application, e.g. hello.py:
from flask import Flask
app = Flask(__name__)
@app.route('/')
def hello():
return "hello"
Monitoring via systemd:
/etc/systemd/system/gunicorn.service
[Unit]
Description=gunicorn daemon
Requires=gunicorn.socket
After=network.target
[Service]
Type=notify
User=...
Group=...
WorkingDirectory=<application_dir>
ExecStart=<application_dir>/bin/gunicorn 'hello:app'
ExecReload=/bin/kill -s HUP $MAINPID
KillMode=mixed
TimeoutStopSec=5
PrivateTmp=true
[Install]
WantedBy=multi-user.target
/etc/systemd/system/gunicorn.socket:
[Unit]
Description=gunicorn socket
[Socket]
ListenStream=/run/gunicorn.sock
SocketUser=www-data
[Install]
WantedBy=sockets.target
Activate and start the service:
systemctl enable --now gunicorn.socket
Test the application (unix socket - gunicorn - flask):
curl --unix-socket /run/gunicorn.sock http
Integrate it with nginx:
http {
upstream flask {
server unix:/run/gunicorn.sock;
}
}
server {
location /... {
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header Host $http_host;
proxy_redirect off;
proxy_pass http://flask/;
}
}
Details on the proxy_pass:
http://flask) makes nginx to forward the original URI as-is to flask.http://unix:/run/gunicorn.sock or http://unix:/run/gunicorn.sock:/path/.Next: TK-Star TK905-4G GPS Tracker