JSFiddle - React, Tailwind, and code Playground

HTML

What need to do?
    <input type="text" id="todotext">
    <button class="new" onclick="addToDo()">Add to todo-list.</button>

JavaScript

<script>
        var addToDo = function () {
            var todo = {task: $("#todotext").val()};
            var json = JSON.stringify(task);
            $.ajax({
                type: "POST",
                url: "http://localhost:8080/",
                data: json,
                contentType: "application/json; charset=utf-8",
                dataType: "json",
                success: function (msg) {
                    console.log(msg);
                }             

            });

        }

    </script>