how to shorten paths in files

It's while since I was writing any serious scripts, but when I was this type of problem was resolved using Pattern-Matching Operators... that was with the korn shell but I think bash is compliant with it.

Just tested and yes it works too in bash.

To get myFile from "https://my.full.path/myFile"
You would do something like

#!/bin/bash
path="http://my.full.path/myFile"
echo ${path##http://*/}

Google I am sure can find you the details of the operators. I think there were just 4 variants.

ok I did a quick google and did not see any links to what I meant on the first screen so here is very short & quick overview.

There were 4 "Pattern-Matching Operators" that I remember

${variable#pattern} - If the pattern matches the start of the variable's value, delete the shortest part that matches and return the rest.
e.g.

path=/home/croo/test/long.file.name
${path#/*/} --> croo/test/long.file.name  

${variable##pattern} - If the pattern matches the start of the variable's value, delete the longest part that matches and return the rest.
e.g.

path=/home/croo/test/long.file.name
${path##/*/} --> long.file.name

${variable%pattern} - If the pattern matches the end of the variable's value, delete the shortest part that matches and return the rest.
e.g.

path=/home/croo/test/long.file.name
${path%.*} --> /home/croo/test/long.file

${variable%%pattern} - If the pattern matches the end of the variable's value, delete the longest part that matches and return the rest.
e.g.

path=/home/croo/test/long.file.name
${path%%.*} --> /home/croo/test/long

And that's it.. they are short & simple but very powerful!