TypeError: Cannot read property 'split' of undefined
   at preferedLang (/app/index.js:53:29)
   at /app/index.js:113:16
   at Layer.handle [as handle_request] (/app/node_modules/express/lib/router/layer.js:95:5)
   at next (/app/node_modules/express/lib/router/route.js:137:13)
   at Route.dispatch (/app/node_modules/express/lib/router/route.js:112:3)
   at Layer.handle [as handle_request] (/app/node_modules/express/lib/router/layer.js:95:5)
   at /app/node_modules/express/lib/router/index.js:281:22
   at Function.process_params (/app/node_modules/express/lib/router/index.js:335:12)
   at next (/app/node_modules/express/lib/router/index.js:275:10)
   at SendStream.error (/app/node_modules/serve-static/index.js:121:7)
   at SendStream.emit (events.js:160:13)
   at SendStream.error (/app/node_modules/send/index.js:270:17)
   at SendStream.onStatError (/app/node_modules/send/index.js:421:12)
   at next (/app/node_modules/send/index.js:763:28)
   at /app/node_modules/send/index.js:771:23
   at FSReqWrap.oncomplete (fs.js:166:21)