waitForEvent(event[, optionsOrPredicate])

Documentation

Grafana k6

Open source

Waits for the event to fire and returns its value. If a predicate function has been set it will pass the value to the predicate function, which must return true for the promise to resolve.

Parameter	Type	Default	Description
event	string	`null`	Name of event to wait for. Currently the `'page'` event is the only one that is supported.
optionsOrPredicate	function\|object	`null`	Optional. If it’s a function, the `'page'` event data will be passed to it and it must return `true` to continue.
optionsOrPredicate.predicate	function	`null`	Optional. Function that will be called when the `'page'` event is emitted. The event data will be passed to it and it must return `true` to continue.
optionsOrPredicate.timeout	number	`30000`	Optional. Maximum time to wait in milliseconds.

Returns

Type	Description
`Promise<Object>`	At the moment a Page object is the only return value

Example

import { browser } from 'k6/x/browser';

export const options = {
  scenarios: {
    browser: {
      executor: 'shared-iterations',
      options: {
        browser: {
          type: 'chromium',
        },
      },
    },
  },
};

export default async function () {
  const context = browser.newContext();

  // Call waitForEvent with a predicate which will return true once at least
  // one page has been created.
  let counter = 0;
  const promise = context.waitForEvent('page', {
    predicate: (page) => {
      if (++counter >= 1) {
        return true;
      }
      return false;
    },
  });

  // Now we create a page.
  const page = context.newPage();

  // Wait for the predicate to pass.
  await promise;
  console.log('predicate passed');

  page.close();
}