Python is the language of choice for controlling the Raspberry Pi’s GPIO pins. It seems only natural then that to interact with your Pi over the web it should run a web server able to handle Python CGI scripts. Following the steps below will get the lightweight nginx web server running on your Pi, handing Python requests off to a uwsgi helper process.

1. Install nginx

   sudo apt-get update
   sudo apt-get upgrade
   sudo apt-get install nginx

2. Add a location to the /etc/nginx/sites-available/default to pass Python requests on to uwsgi. This needs to be placed inside the “server” block of the configuration, for example right after one of the existing “location” sections.

   location ~ \.py$ {
   uwsgi_pass 127.0.0.1:9000;
   include uwsgi_params;
   uwsgi_modifier1 9;
   }

3. Create a Python CGI script at /usr/share/nginx/www/hello.py

   #!/usr/bin/env python
   print "Content-type: text/html\n\n"
   print "<h1>Hello World</h1>"

4. Start nginx

   sudo /etc/init.d/nginx start

5. Build and install the uwsgi with the cgi plugin

   curl http://uwsgi.it/install | bash -s cgi /home/pi/uwsgi
   sudo mv /home/pi/uwsgi /usr/local/bin

6. Create the file /etc/uwsgi.ini

   [uwsgi]
   plugins = cgi
   socket = 127.0.0.1:9000
   module = pyindex
   cgi = /usr/share/nginx/www
   cgi-allowed-ext = .py
   cgi-helper = .py=python

7. Create the file /usr/share/nginx/www/hello.py

   #!/usr/bin/env python
   print "Content-type: text/html\n\n"
   print "<h1>Hello World</h1>"

8. Create an init script for uwsgi at /etc/init.d/uwsgi

   #!/bin/sh### BEGIN INIT INFO
   # Provides: uwsgi
   # Required-Start: $local_fs $remote_fs $network $syslog
   # Required-Stop: $local_fs $remote_fs $network $syslog
   # Default-Start: 2 3 4 5
   # Default-Stop: 0 1 6
   # Short-Description: starts the uwsgi cgi socket
   # Description: starts uwsgi using start-stop-daemon
   ### END INIT INFO
   
   PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
   DAEMON=/usr/local/bin/uwsgi
   NAME=uwsgi
   DESC=uwsgi
   DAEMON_OPTS=/etc/uwsgi.ini
   
   test -x $DAEMON || exit 0
   
   set -e
   
   . /lib/lsb/init-functions
   
   case "$1" in
   start)
   echo -n "Starting $DESC: "
   start-stop-daemon --start --quiet --pidfile /var/run/$NAME.pid \
   --make-pidfile --chuid www-data --background \
   --exec $DAEMON -- $DAEMON_OPTS || true
   echo "$NAME."
   ;;
   
   stop)
   echo -n "Stopping $DESC: "
   start-stop-daemon --stop --quiet --pidfile /var/run/$NAME.pid \
   --exec $DAEMON || true
   echo "$NAME."
   ;;
   
   restart|force-reload)
   echo -n "Restarting $DESC: "
   start-stop-daemon --stop --quiet --pidfile \
   /var/run/$NAME.pid --exec $DAEMON || true
   sleep 1
   start-stop-daemon --start --quiet --pidfile /var/run/$NAME.pid \
   --chuid www-data --background \
   --exec $DAEMON -- $DAEMON_OPTS || true
   echo "$NAME."
   ;;
   
   status)
   status_of_proc -p /var/run/$NAME.pid "$DAEMON" uwsgi && exit 0 || exit $?
   ;;
   *)
   echo "Usage: $NAME {start|stop|restart|status}" >&2
   exit 1
   ;;
   esac
   
   exit 0

9. Start uwsgi and configure it to start on boot

   sudo chmod +x /etc/init.d/uwsgi
   sudo /etc/init.d/uwsgi start
   sudo update-rc.d uwsgi defaults

10. Open up your web browser and go to http://{your pi’s ip address}/hello.py
    If you’re using the browser on your Pi then you could instead go to http://localhost/hello.py
    If you see the message “Hello World” then everything is working.