node-app/public/index.html
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="x-ua-compatible" content="ie=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- The above 3 meta tags *must* come first in the head; any other head content must come *after* these tags -->
<title>Page Title</title>
<meta name="description" content="something">
<meta name="author" content="me">
</head>
<body>
<div class="main">
<form action="http://locahost:3000/submit" method="get" class="form">
<div>
<label for="content">
content as JSON
</label>
<input type="text" name="content" id="content" required>
<div>
<input type="submit" value="Send! ">
</div>
</div>
</form>
</div>
</body>
</html>