istioctl version selector

istioselect

#!/bin/bash

# Simple script to help configuring which istio CLI to use when you
# have a need to keep multiple versions and switch between them.

# Install and notes:
# 1. put this in /usr/local/bin and chmod +x
# 2. keep all the versions of istioctl in the /Applications directory
# 3. name istioctl executables with corresponding version - e.g. /Applications/istioctl-1.4.8


prompt="Please select an istioctl version:"
options=( $(ls /Applications/istioctl* | xargs -0) )

PS3="$prompt "
select opt in "${options[@]}" "Quit" ; do
    if (( REPLY == 1 + ${#options[@]} )) ; then
        exit

    elif (( REPLY > 0 && REPLY <= ${#options[@]} )) ; then
        echo  "You picked $REPLY"
        break

    else
        echo "Invalid option. Try another one."
    fi
done

echo "Switching istio to version at $opt"

ln -sf $opt /usr/local/bin/istioctl

istioctl version