Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.
WebSocket.addEventListener(event, handler)
Set up handler functions for various events on the WebSocket connection. You can define multiple handlers for the same event.
Example
A k6 script that demonstrates how to add multiple event listeners for the WebSocket message
connection event.
import { WebSocket } from 'k6/experimental/websockets';
export default function () {
const ws = new WebSocket('ws://localhost:10000');
ws.onopen = () => {
console.log('connected');
ws.send(Date.now().toString());
};
ws.onmessage = () => {
console.log('onmessage event handler!');
};
// Multiple event handlers on the same event
ws.addEventListener('message', () => {
console.log('addEventListener event handler!');
ws.close();
});
}
The preceding example uses a WebSocket echo server, which you can run with the following command:
$ docker run --detach --rm --name ws-echo-server -p 10000:8080 jmalloc/echo-server