Documentationbreadcrumb arrow Grafana k6breadcrumb arrow JavaScript APIbreadcrumb arrow k6/experimentalbreadcrumb arrow browserbreadcrumb arrow BrowserContextbreadcrumb arrow waitForEvent(event[, optionsOrPredicate])
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.

ParameterTypeDefaultDescription
eventstringnullName of event to wait for. Currently the 'page' event is the only one that is supported.
optionsOrPredicatefunction|objectnullOptional. If it’s a function, the 'page' event data will be passed to it and it must return true to continue.
optionsOrPredicate.predicatefunctionnullOptional. 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.timeoutnumber30000Optional. Maximum time to wait in milliseconds.

Returns

TypeDescription
Promise<Object>At the moment a Page object is the only return value

Example

JavaScript 
import { browser } from 'k6/experimental/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();
}