add script to set up tpf-switchboard as a service

setup.sh

+#!/bin/bash
+
+USER="tpf-switchboard"
+APP_PATH="$( cd "$(dirname "$0")" >/dev/null 2>&1 ; pwd -P )"
+APP_NAME="switchboard"
+SERVICE_NAME="tpf-switchboard"
+LISTEN_PORT=3591
+LISTEN_ADDRESS="0.0.0.0"
+
+# are we root?
+if [ "$(whoami)" != "root" ]
+then
+  echo "We are not running as root. Exiting now."
+  exit 1
+fi
+
+# Install flask
+if ! which flask > /dev/null
+then
+  apt-get install python3-flask || exit 1
+fi
+
+# Install gunicorn3
+if ! which gunicorn3 > /dev/null
+then
+  apt-get install gunicorn3 || exit 1
+fi
+
+# add user to the system
+if ! id -u "$USER" > /dev/null 2>&1
+then
+  useradd -r -s /usr/sbin/nologin $USER || exit 1
+fi
+
+SYSTEMD_UNIT_CONTENT="
+[Unit]
+Description=tpf-switchboard - manager for udp proxies
+After=syslog.target
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/gunicorn3 \\
+            --bind $LISTEN_ADDRESS:$LISTEN_PORT \\
+	    --chdir $APP_PATH \\
+	    $APP_NAME:app
+User=$USER
+Group=$USER
+
+[Install]
+WantedBy=multi-user.target
+"
+
+echo "$SYSTEMD_UNIT_CONTENT" > /etc/systemd/system/${SERVICE_NAME}.service
+systemctl daemon-reload
+systemctl enable ${SERVICE_NAME}.service
+systemctl start ${SERVICE_NAME}.service