public/signup.html

<!doctype html>
<html lang="en">
 
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
  <title>Sign Up Page</title>
  <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T"
    crossorigin="anonymous">
  <link href="assets/css/main.css" rel="stylesheet">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
</head>
 
<body class="text-center">
  <form class="form-signin">
    <h1 class="h3 mb-3 font-weight-normal">Sign Up</h1>
    <label for="email" class="sr-only">Email address</label>
    <input type="email" id="email" class="form-control" placeholder="Email address" required autofocus>
    <label for="password" class="sr-only">Password</label>
    <input type="password" id="password" class="form-control" placeholder="Password" required>
    <label for="name" class="sr-only">Name</label>
    <input type="text" id="name" class="form-control" placeholder="Name" required>
    <a class="btn btn-lg btn-primary btn-block" onClick="signUp()">Sign up</a>
    <a href="/index.html">Already have an account? Login here.</a>
  </form>
  <script>
    function signUp() {
      var data = {
        email: document.forms[0].elements[0].value,
        password: document.forms[0].elements[1].value,
        name: document.forms[0].elements[2].value
      };
      $.ajax({
        type: 'POST',
        url: '/signup',
        data,
        // On sucess, sign the user in
				success: function (data) {
          window.alert('user created successfully.');
      		$.ajax({
        		type: 'POST',
        		url: '/login',
        		data,
        		success: function (data) {
          	window.location.replace('/game.html');
        	},
        	error: function (xhr) {
          	window.alert(JSON.stringify(xhr));
          	window.location.replace('/index.html');
        	}
      	});
        },
        
				error: function (xhr) {
          window.alert(JSON.stringify(xhr));
          window.location.replace('/signup.html');
        }
      });
    }
  </script>
</body>
 
</html>