This is documentation for the next version of K6. For the latest stable release, go to the latest version.
WebSockets
Here’s a load test for the QuickPizza WebSocket API, available on https://quickpizza.grafana.com/ws.
Multiple VUs connect using a VU-indexed user name, and send random messages.
Each VU receives messages sent by all other VUs.
import { randomString, randomIntBetween } from 'https://jslib.k6.io/k6-utils/1.2.0/index.js';
import ws from 'k6/ws';
import { check, sleep } from 'k6';
const sessionDuration = randomIntBetween(3000, 6000);
export const options = {
vus: 10,
iterations: 10,
};
export default function () {
const url = `wss://quickpizza.grafana.com/ws`;
const params = { tags: { my_tag: 'my ws session' } };
const user = `user_${__VU}`;
const res = ws.connect(url, params, function (socket) {
socket.on('open', function open() {
console.log(`VU ${__VU}: connected`);
socket.send(JSON.stringify({ msg: 'Hello!', user: user }));
socket.setInterval(function timeout() {
socket.send(
JSON.stringify({
user: user,
msg: `I'm saying ${randomString(5)}`,
foo: 'bar',
})
);
}, randomIntBetween(1000, 2000));
});
socket.on('ping', function () {
console.log('PING!');
});
socket.on('pong', function () {
console.log('PONG!');
});
socket.on('close', function () {
console.log(`VU ${__VU}: disconnected`);
});
socket.on('message', function (message) {
const data = JSON.parse(message);
console.log(`VU ${__VU} received message: ${data.msg}`);
});
socket.setTimeout(function () {
console.log(`VU ${__VU}: ${sessionDuration}ms passed, leaving the website`);
socket.send(JSON.stringify({ msg: 'Goodbye!', user: user }));
}, sessionDuration);
socket.setTimeout(function () {
console.log(`Closing the socket forcefully 3s after graceful LEAVE`);
socket.close();
}, sessionDuration + 3000);
});
check(res, { 'Connected successfully': (r) => r && r.status === 101 });
sleep(1);
}