JavaScript cookies and ensuring log in before accessing webpages -

i want way log in , store users details (maybe in cookie?) securely using javascript.

the main want go http://localhost:3000 http://localhost:3000/welcome can using below code document.location.replace('./welcome');

however, if type in http://localhost:3000/welcome address take me straight there instead of asking auth. how can login page thrown in front of page if no 1 logged in? tutorials on this? thanks

you need server side. other important thing note javascript client side , not secure @ all.