var releaseRegex = /release (..)/ var codenameRegex = /\((.*)\)/ module.exports = function fedoraCustomLogic(os,file,cb) { var release = file.match(releaseRegex) if(release && release.length === 2) os.release = release[1] var codename = file.match(codenameRegex) if(codename && codename.length === 2) os.codename = codename[1] cb(null,os) }