PlaywrightPHP

Observing traffic

Observe requests and responses without making the test depend on every background call.

Network evidence is useful when a user action depends on one backend exchange. It is less useful when the test records every request and then tries to infer whether the product worked.

Keep two questions separate:

  • What did the browser send? Inspect the request.
  • What did the application return? Inspect the response.

The final assertion should normally still describe what the user sees.

Observe without changing behaviour

Events are read-only. Register them before the action that emits the traffic:

php
$page->events()->onRequest(static function ($request): void {
    printf('> %s %s'.PHP_EOL, $request->method(), $request->url());
});

$page->goto('https://app.example.test/dashboard');

Use broad listeners for temporary diagnostics. For a test assertion, wait for the one exchange that belongs to the scenario.

Tie a response to an action

The PHP process cannot click while waitForResponse() is blocking. Pass the small browser-side action as a JavaScript expression so the listener is armed before the click:

php
$response = $page->waitForResponse('**/api/orders', [
    'action' => 'document.querySelector("[data-testid=refresh-orders]").click()',
]);

self::assertSame(200, $response->status());

expect($page->getByRole('heading', ['name' => 'Orders']))
    ->toBeVisible();

The status explains the backend exchange. The locator assertion proves that the page reached the user-visible result.

Keep this exception narrow. When the response itself is not part of the requirement, click through a locator and assert the visible result instead.

Choose the right signal

Need Use
Print temporary diagnostics request or response events
Prove an action sent one call wait for the matching request
Tie an action to a backend result wait for the matching response
Change, block, or replace traffic Routing
Test an endpoint without rendering API requests

Match narrowly enough to identify the call: URL, method, and meaningful query parameters when needed. Avoid assertions on analytics, preloads, polling, or third-party noise unless they are the product contract.

Common mistakes

  • Registering the listener after navigation or the click.
  • Treating a 200 response as proof that the UI updated.
  • Asserting every request made during page load.
  • Matching only a broad URL fragment when several calls share it.
  • Forgetting that a request can fail before any response exists.

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