script for file extention verification

check_file_extention.js

/*
script for file extention verification
*/

var path = 'path/to/file';
var imageExt = ['jpeg','jpg','png','gif','tiff']; //specify allowed file extentions
var fileExt = path.split('.');
var checkExist = imageExt.indexOf(fileExt[fileExt.length-1]); // -1 if the file extention does not exist in imageExt
if (checkExist === -1){
  console.log('File type not supported, please use '+ imageExt); 
  return;
}