Params

A module with a better and standard API exists

The new k6/experimental/websockets API partially implements the WebSockets API living standard.

When possible, we recommend using the new API. It uses a global event loop for consistency with other k6 APIs and better performance.

Params is an object used by the WebSocket methods that generate WebSocket requests. Params contains request-specific options like headers that should be inserted into the request.

Example of custom metadata headers and tags

A k6 script that will make a WebSocket request with a custom header and tag results data with a specific tag

import ws from 'k6/ws';

export default function () {
  const url = 'ws://echo.websocket.org';
  const params = {
    headers: { 'X-MyHeader': 'k6test' },
    tags: { k6test: 'yes' },
  };
  const res = ws.connect(url, params, function (socket) {
    socket.on('open', function () {
      console.log('WebSocket connection established!');
      socket.close();
    });
  });
}