JMICO / Beekeeper-0.10 / examples / websocket / client.html 
<!DOCTYPE HTML>
<html>
<head>
<title>JSON-RPC over MQTT example</title>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
<script language="Javascript" type="text/javascript" defer src="https://cdnjs.cloudflare.com/ajax/libs/mqtt/4.3.7/mqtt.min.js"></script>
<script language="Javascript" type="text/javascript" defer src="https://cdnjs.cloudflare.com/ajax/libs/pako/2.1.0/pako_inflate.min.js"></script>
<script language="Javascript" type="text/javascript" defer src="js/config.js"></script>
<script language="Javascript" type="text/javascript" defer src="js/beekeeper.js"></script>
<script language="Javascript" type="text/javascript" defer src="js/calculator.js"></script>
<style type="text/css">

body {
    padding: 40px;
    font-size: 11pt;
    font-family: sans-serif;
}

#expr {
    font-size: 14pt; font-family: sans-serif;
    width: 380px;
    color: #000000;
    padding: 6px;
    padding-left: 12px;
    margin: 6px;
    border: solid 2px #6699CC;
    border-radius: 6px;
}
 
#send {
    font-size: 12pt; font-family: sans-serif;
    width: 80px;
    color: #000000;
    padding: 6px;
    margin: 6px;
    border: solid 2px #6699CC;
    background-color: #6699CC;
    border-radius: 6px;
}

#result {
    font-size: 16pt; font-family: sans-serif;
    width: 470px;
    min-height: 28px;
    margin: 6px;
    padding: 12px;
    border: solid 1px #6699CC;
    border-radius: 6px;
}

.result.success {
    background-color: #A0FFA0;
}

.result.error {
    background-color: #FFA0A0;
}

</style>
</head>

<body>
<input type="text" id="expr" value="2 + 2" />
<input type="button" id="send" value=" = " onclick="Calc.eval_expr()" />
<div id="result"></div>
<p>&nbsp; JSON-RPC traffic is being dumped to console.</br />
&nbsp; "Server error" means that the remote method died.</p>
</body>
</html>