Shell script to select fastest VPN location from available list

vpn-refresh.sh

#!/bin/bash

# Set your VPN up with this guide: https://gist.github.com/superjamie/ac55b6d2c080582a3e64

# This runs nicely on a Raspberry Pi that is setup to be your gateway.
# Requires:  speedtest-cli, openvpn

# Assuming you have config files of:
# /etc/openvpn/newyork.conf
# /etc/openvpn/chicago.conf
# /etc/openvpn/miami.conf

# Create a text file called /etc/openvpn/list.txt that looks like:
# newyork
# chicago
# miami

# Then run:
# sudo /etc/openvpn/vpn-refresh.sh /etc/openvpn/list.txt

# The fastest location will be auto detected.

if [ "$1" = "" ];
then
        echo "Usage: $0 vpn-list.txt [acceptable-speed]"
        echo "  vpn-list.txt: text file with list of config files setup to pass to openvpn service."
        echo "  acceptable-speed: (Optional) minimum speed to automatically accept and skip scanning additional VPNs."
        exit 1
fi

# default speed that short circuits the process to 1gbps
ACCEPTSPEED=1000

if [ "$2" != "" ];
then
        ACCEPTSPEED=$2
fi

SERVERCOUNT=`wc -l "$1" | cut -d ' ' -f 1`
SPEEDGOOD=0
SERVERNUM=0
BESTSPEED=0
BESTSERVER=0
SERVERLIST=$1

echo Found $SERVERCOUNT servers in $1.
echo

testspeed ()
{
mbitdown=`speedtest-cli | grep Download | cut -d ' ' -f 2 | cut -d '.' -f 1`
if [ "$mbitdown" -gt "$BESTSPEED" ]; then
        BESTSPEED=$mbitdown
        BESTSERVER=$SERVERNUM
fi

echo Download speed for $SERVER is $mbitdown.
echo
}

nextserver ()
{
if [ "$SERVERNUM" -eq "$SERVERCOUNT" ]; then
        exit 0
fi

((SERVERNUM++))
SERVER=`sed -n "${SERVERNUM}p" "${SERVERLIST}"`
}

resetvpn ()
{
echo -n Flipping VPN to $SERVER
# stop existing VPN connection
service openvpn stop; sleep 1;
echo -n "."
IP=`curl -s ipinfo.io/ip`
service openvpn@$SERVER start;
NEWIP=`curl -s ipinfo.io/ip`
echo -n "."

# wait 1 second while checking if IP address has changed each time
# this makes sure we are connected to the new server before moving on
while [ "$IP" = "$NEWIP" ]
do
        echo -n "."
        sleep 1
        NEWIP=`curl -s ipinfo.io/ip`
done
echo " FLIPPED!"
}

for i in `seq 1 ${SERVERCOUNT}`;
do
        if [ $BESTSPEED -lt $ACCEPTSPEED ];
        then
                nextserver
                resetvpn
                testspeed
        fi
done


if [ $BESTSPEED -lt $ACCEPTSPEED ];
then
        ((SERVERNUM=BESTSERVER-1))
        nextserver
        resetvpn
fi