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Directory path . web , gh , client side templating tests .

HTML Document File : template.html 

<!doctype html>
<html>
<body>
<script src="jquery-3.3.1.min.js"></script>
<meta charset="utf-8">
<script>

function linkFetch(event){
    var action = document.all.action_link.dataset.action
    $.get('login_action.php?action='+action).done(init)
}

function logged(status){
    var action
    if(status=='in') action='logout'
    else if(status=='out') action='login'
    else{
        console.log('login status not valid:', status)
        return
    }
    document.all.login_manager.innerHTML='<button id=action_link onclick=linkFetch() data-action='+action+'>'+action+'</button>'
    $('#out').load('private.php')
}

function init(){
    $.get('logged.php').done(status => logged(status))
}
$(init())
</script>
<div id=login_manager></div>
<div id=out></div>
</body>
</html>