in lambda/index.js [105:118]
function computeId(url, salt) {
if(salt) {
url = salt + '$' + url
}
// For demonstration purposes MD5 is fine
let md5 = crypto.createHash('md5');
// Compute the MD5, then use only the first 40 bits
let h = md5.update(url).digest('hex').slice(0, 10);
// Return results in base32 (hence 40 bits, 8*5)
return parseInt(h, 16).toString(32);
}