In a shell / ansible / packer stack find and replace var names.

var_rename.py3

import re
import fileinput
import sys

old_caps_underscored_var=sys.argv[1]
old_lower_underscored_var=old_caps_underscored_var.lower()
old_lower_dashed_var=old_lower_underscored_var.replace("_","-")

new_caps_underscored_var=sys.argv[2]
new_lower_underscored_var=new_caps_underscored_var.lower()
new_lower_dashed_var=new_lower_underscored_var.replace("_","-")

filename=sys.argv[3]

def convert (old_var,new_var,line):
    regex = r'(?<![a-zA-Z]-)\b' + old_var + r'\b(?!-[a-zA-Z])'
    return re.sub(regex,new_var,line.rstrip('\n'))

with fileinput.input(filename, inplace=True, backup='.bak') as file:
    for line in file:
        line=convert(old_caps_underscored_var,new_caps_underscored_var,line)
        line=convert(old_lower_underscored_var,new_lower_underscored_var,line)
        line=convert(old_lower_dashed_var,new_lower_dashed_var,line)
        print(line)