supervisord + gunicorn + nginx

gunicorn.conf

[program:gunicorn]
command=/bin/gunicorn -w 4 myapp:app
environment=MY_ENV=/var/null
user=www-data

nginx.conf

user www-data;
worker_processes  1;

error_log  /var/log/nginx/error.log;
pid        /var/run/nginx.pid;

events {
    worker_connections  1024;
}

http {
    include mime.types;
    default_type application/octet-stream;
    access_log /var/log/nginx/nginx.access.log combined;
    sendfile on;

    upstream app_server {
        server 127.0.0.1:8000 fail_timeout=0;
    }

    server {
        listen *:8420;
        server_name __;
        rewrite ^ https://example.com permanent;
    }

    server {
        listen 80 default;
        client_max_body_size 4G;
        server_name _;

        real_ip_header X-Forwarded-For;
        set_real_ip_from 0.0.0.0/0;
        keepalive_timeout 5;

        location / {
            # checks for static file, if not found proxy to app
            try_files $uri @proxy_to_app;
        }

        location @proxy_to_app {
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header Host $http_host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_pass       http://app_server;
            proxy_redirect   default;
            proxy_redirect   http://example.com/ https://example.com/;
            proxy_buffering  off;
        }
    }
}

supervisor.conf

[unix_http_server]
file=/var/run/supervisor.sock   ; (the path to the socket file)

[supervisord]
logfile=/var/log/supervisord.log ; (main log file;default $CWD/supervisord.log)
logfile_maxbytes=50MB        ; (max main logfile bytes b4 rotation;default 50MB)
logfile_backups=10           ; (num of main logfile rotation backups;default 10)
loglevel=info                ; (log level;default info; others: debug,warn,trace)
pidfile=/var/run/supervisord.pid ; (supervisord pidfile;default supervisord.pid)
nodaemon=false               ; (start in foreground if true;default false)
minfds=1024                  ; (min. avail startup file descriptors;default 1024)
minprocs=200                 ; (min. avail process descriptors;default 200)

[rpcinterface:supervisor]
supervisor.rpcinterface_factory = supervisor.rpcinterface:make_main_rpcinterface

[supervisorctl]
serverurl=unix:///var/run/supervisor.sock ; use a unix:// URL  for a unix socket

[include]
files = supervisor/*.conf

supervisor.sh

#! /bin/bash -e
### BEGIN INIT INFO
# Provides: supervisor
# Required-Start: ec2-get-user-data
# Required-Stop:
# Should-Start:
# Should-Stop:
# Default-Start: 2
# Default-Stop:
# Description: Start supervisord
### END INIT INFO

SUPERVISORD=/bin/supervisord
PIDFILE=/var/run/supervisor.pid
OPTS="-c /etc/supervisord.conf"

test -x $SUPERVISORD || exit 0

. /lib/lsb/init-functions

export PATH="${PATH:+$PATH:}/usr/local/bin:/usr/sbin:/sbin"

case "$1" in
  start)
    log_begin_msg "Starting Supervisor daemon manager..."
    start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $SUPERVISORD -- $OPTS || log_end_msg 1
    log_end_msg 0
    ;;
  stop)
    log_begin_msg "Stopping Supervisor daemon manager..."
    start-stop-daemon --stop --quiet --oknodo --pidfile $PIDFILE || log_end_msg 1
    log_end_msg 0
    ;;

  restart|reload|force-reload)
    log_begin_msg "Restarting Supervisor daemon manager..."
    start-stop-daemon --stop --quiet --oknodo --retry 30 --pidfile $PIDFILE
    start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $SUPERVISORD -- $OPTS || log_end_msg 1
    log_end_msg 0
    ;;

  *)
    log_success_msg "Usage: /etc/init.d/supervisor {start|stop|reload|force-reload|restart}"
    exit 1
esac

exit 0