Mastering the waitForUrl Behaviour in Playwright: A Comprehensive Guide

Are you tired of dealing with flaky tests and uncertain waits in your Playwright automation? Do you want to take your automation game to the next level? Look no further! In this article, we’ll dive into the wonderful world of `waitForUrl` behaviour in Playwright, and show you how to harness its power to write robust and reliable tests.

What is `waitForUrl` behaviour?

The `waitForUrl` behaviour is a powerful feature in Playwright that allows you to wait for a specific URL to be loaded in the browser. This is particularly useful when you want to ensure that a certain page has loaded before performing actions or assertions.

Why do I need `waitForUrl`?

Without `waitForUrl`, your tests might fail due to premature actions or assertions. Imagine you’re testing a login flow, and you want to assert that the user is redirected to the dashboard page after successful login. Without `waitForUrl`, your test might try to assert the dashboard page before it’s even loaded, leading to flaky tests and failed assertions.

Using `waitForUrl` in Playwright

To use `waitForUrl` in Playwright, you need to call the `waitForUrl` method on a `Page` object, passing the expected URL as an argument. Here’s an example:

const playwright = require('playwright');

(async () => {
  const browser = await playwright.chromium.launch();
  const context = await browser.newContext();
  const page = await context.newPage();

  await page.goto('https://example.com/login');
  await page.waitForUrl('https://example.com/dashboard');

  // Assert that the dashboard page is loaded
  await page.waitForSelector('text=Dashboard');

  await browser.close();
})();

In this example, we first navigate to the login page and then wait for the dashboard page to load using `waitForUrl`. Once the dashboard page is loaded, we assert that the “Dashboard” text is present on the page.

Waiting for URL patterns

Sometimes, you might want to wait for a URL pattern rather than an exact URL. Playwright allows you to do this using the `url` option with a regular expression pattern. Here’s an example:

await page.waitForUrl(/\/dashboard\/.*/, { timeout: 3000 });

In this example, we wait for any URL that matches the pattern `/dashboard/*` using a regular expression. The `timeout` option specifies the maximum time to wait for the URL to load.

Waiting for URL with options

You can customize the `waitForUrl` behaviour by passing options as an object. Here are some available options:

Option	Description
timeout	Maximum time to wait for the URL to load (in milliseconds)
waitUntil	Specifies when to consider the URL loaded (e.g., “load”, “domcontentloaded”, etc.)

Here’s an example of using options with `waitForUrl`:

await page.waitForUrl('https://example.com/dashboard', {
  timeout: 5000,
  waitUntil: 'networkidle0',
});

In this example, we wait for the dashboard page to load with a timeout of 5 seconds and wait until the network is idle (no more than 0 active networks requests). This ensures that the page is fully loaded before proceeding with the test.

Timeouts and retries

By default, `waitForUrl` will timeout after 30 seconds if the expected URL is not loaded. You can customize the timeout using the `timeout` option. If the timeout is exceeded, the test will fail.

Playwright also allows you to retry the `waitForUrl` operation if it fails. You can use the `retry` option to specify the number of retries and the delay between retries.

await page.waitForUrl('https://example.com/dashboard', {
  timeout: 5000,
  retry: {
    retries: 3,
    delay: 1000,
  },
});

In this example, we retry the `waitForUrl` operation up to 3 times with a delay of 1 second between retries if the expected URL is not loaded within the timeout period.

Best practices for using `waitForUrl`

Here are some best practices to keep in mind when using `waitForUrl`:

• Use `waitForUrl` with a specific URL or URL pattern to avoid waiting for unnecessary pages.
• Set a reasonable timeout to avoid test timeouts and flakiness.
• Use `waitUntil` option to specify when to consider the URL loaded.
• Use retries to handle intermittent failures and network issues.
• Avoid using `waitForUrl` with vague URL patterns or wildcards, as it may lead to unnecessary waits.

Conclusion

In this article, we’ve explored the `waitForUrl` behaviour in Playwright and demonstrated its power in writing robust and reliable tests. By mastering `waitForUrl`, you can ensure that your tests are more stable and efficient, and that you’re waiting for the right pages to load before performing actions or assertions.

Remember to use `waitForUrl` judiciously, with specific URLs or URL patterns, and with reasonable timeouts and retries. By following best practices and understanding the `waitForUrl` behaviour, you can take your automation testing to the next level with Playwright.

Here are 5 questions and answers about the “waitForUrl” behavior in Playwright:

Frequently Asked Question

Get the lowdown on Playwright’s waitForUrl behavior with these frequently asked questions!