grafana/k6 · error

waiting for page event

Error message

waiting for page event %q: %w

What it means

Thrown when the underlying p.WaitForEvent call fails after the options parsed and the wait started. It wraps the raw failure: most commonly a timeout waiting for the event within p.Timeout() (the page/action timeout), but also browser or context closing mid-wait, or an error escaping the predicate.

Solutions

1. Increase the timeout: pass { timeout: 60000 } or raise the default with page.setDefaultTimeout(60000) / newContext({ actionTimeout }).
2. Verify the triggering action actually happens (the click/navigation that should produce the event) and that the event name matches a mapped event.
3. If using a predicate, confirm it can return true (test it against a captured event).
4. Catch the rejection and fail the iteration with a descriptive k6 check message instead of an unhandled promise rejection.

Example fix

// before
const res = await page.waitForEvent('response');

// after
try {
  const res = await page.waitForEvent('response', { timeout: 60000 });
} catch (e) {
  check(null, { 'response event received': () => false });
  throw e;
}

try {
  const ev = await page.waitForEvent('response', { timeout: 60000 });
} catch (e) {
  if (/waiting for page event/.test(e.message)) {
    check(null, { 'event arrived in time': () => false });
  }
  throw e;
}

When it happens

Trigger: page.waitForEvent('response', { timeout: 1000 }) when no matching network exchange happens in time; the page navigating away or being closed before the event fires; a predicate that never returns true; running against a slow site under load where responses exceed the default 30s action timeout.

Common situations: Waiting for events that never occur because the selector/navigation step before them failed silently; tight timeouts in CI; heavy pages under k6 load where responses are slower than scripted; browser context closed by script end while an event wait is in flight.

Related errors

• executing waitForEvent predicate
• parsing waitForEvent options
• waitForEvent does not support mapping for event
• an error occurred communicating with k6 Cloud
• " " attribute is only supported for roles: "`).join(", ")}

AI-assisted analysis of grafana/k6@8d06114777 (2026-08-18). Data as JSON: /api/errors/3d100b5131f641c5. Report an issue: GitHub.

Appendix: source

Thrown at internal/js/modules/k6/browser/browser/page_mapping.go:722

			return promise(vu, func() (any, error) {
				rpe, err := p.WaitForEvent(event, popts, func(pe common.PageEvent) (bool, error) {
					if fn == nil {
						return true, nil
					}
					return queueTask(ctx, tq, func() (bool, error) {
						m, err := mapPageEvent(vu, pe)
						if err != nil {
							return false, err
						}
						v, err := fn(sobek.Undefined(), vu.Runtime().ToValue(m))
						if err != nil {
							return false, fmt.Errorf("executing waitForEvent predicate: %w", err)
						}
						return v.ToBoolean(), nil
					})()
				})
				if err != nil {
					return nil, fmt.Errorf("waiting for page event %q: %w", event, err)
				}
				return mapPageEvent(vu, rpe)
			}), nil
		},
		"workers": func() *sobek.Object {
			workers := p.Workers()
			mws := make([]mapping, 0, len(workers))
			for _, w := range workers {
				mw := mapWorker(vu, w)
				mws = append(mws, mw)
			}
			return rt.ToValue(mws).ToObject(rt)
		},
	}
	maps["$"] = func(selector string) *sobek.Promise {
		return promise(vu, func() (any, error) {
			eh, err := p.Query(selector)
			if err != nil {

View on GitHub (pinned to 8d06114777)