eg. node ./github-to-jsdelivr.js "https://github.com/phlinhng/my-scripts/blob/master/README.md"

github-to-jsdelivr.js

let github2jsdelivr = (_url) => {
  regex = {"blob": /(.+)github.com\/(.+)\/(.+)\/blob\/(.+)\/(.+)/,
  "tree": /(.+)github.com\/(.+)\/(.+)\/blob\/(.+)\/(.+)/};
  if(_url.match(regex.tree)){
    return _url.replace(regex.tree, "$1cdn.jsdelivr.net/gh/$2/$3@$4/$5");
  }else if(_url.match(regex.blob)){
    return _url.replace(regex.blob, "$1cdn.jsdelivr.net/gh/$2/$4@$4/$5");
  }else{
    return _url;
  }
}

console.log(github2jsdelivr(process.argv[2]));