Websocket

Websocket publisher transport emits processed events to subscribed clients. Events are serialised as Json using the JsonStreamEventFormatter.

Driver details

io.javalin:javalin:5.6.3

Example configuration

websocketPublisher:
  topic: quotes

This simple example leverages the default setting resulting in events published as StreamEvent Json object to connected clients.

Example Websocket client

Use the below example to validate websocket data streaming. If you are using Chrome open up the Developer tools console tab and click the Start Streaming button on the page to stream events from the Joule process. 

<!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=1.0">
    <title>WebSocket Client</title>
</head>

<body>
    <button onclick="contactServer">Start Streaming</button>
</body>

<script>
    const socket = new WebSocket('ws://localhost:7070/joule/ws/stream/quotes');
    socket.addEventListener('open', function (event) {
        socket.send('Connection Established');
    });

    socket.addEventListener('message', function (event) {
        console.log(event.data);
    });

    const contactServer = () => {
        socket.send("Initialize");
    }
</script>
</html>

Core Attributes

Available configuration parameters

AttributeDescriptionData TypeRequired

topic

User defined topic this stream relates too

String

PreviousRabbitMQNextSQL Databases

Last updated