> For the complete documentation index, see [llms.txt](https://docs.fractalworks.io/joule/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fractalworks.io/joule/components/connectors/sinks/websocket.md).
# WebSocket
## Overview
The **WebSocket Publisher Transport** enables real-time event streaming to web clients, ideal for dashboards and interactive applications. Processed events are published as Json to subscribing client processes.
The example WebSocket client provided connects to a local WebSocket server (`ws://localhost:7070/joule/ws/stream/quotes`) and logs incoming event data to the browser console, allowing users to verify the streaming functionality.
{% hint style="info" %}
**Client library:** [io.javalin:javalin:5.6.3](https://mvnrepository.com/artifact/io.javalin/javalin/5.6.3)
{% endhint %}
## Examples & DSL attributes
This simple example leverages the default setting resulting in events published as `StreamEvent` JSON object to connected clients.
```yaml
websocketPublisher:
topic: quotes
```
### Example client
This HTML page acts as a WebSocket client to test data streaming from a Joule server.
Open it in Chrome, go to **Developer Tools > Console**, and click `Start Streaming` to view live event data streamed from `ws://localhost:7070/joule/ws/stream/quotes`.
```html
WebSocket Client
```
### Attributes schema
Attribute
Description
Data Type
Required
topic
User defined topic this stream relates too
String
true
---
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