Implementing Dynamic Element Locators in Playwright Automation

In the web development world quality assurance more or less refers to making sure the website or application functions seamlessly across environments. It is a tedious and lengthy process to ensure 100% functionality.

This is where automated testing comes in, and another major player in the form of a testing framework is Playwright. Playwright is the sort of tool that developers and testers can use to automate web browser interactions similar to Selenium.

Playwright comes with all the abilities to test Chromium, WebKit, and Firefox browsers and branded browsers such as Google Chrome and Microsoft Edge. It ensures that everything goes on smoothly for every user, regardless of the chosen browser.

However, automated testing faces a big challenge: dealing with element locators. These markers tell the testing tool where to click, type, or read from on a webpage.

However, web pages change often, and this can make the markers, or locators, outdated quickly. When locators don’t work, tests fail, even if the website is fine. That’s why there’s a growing need for dynamic locators in modern web app testing.

Playwright Automation,

Understanding Element Locators in Playwright

Element locators are the backbone of web automation. Think of them as the GPS for the Playwright, guiding it to the right spot on a webpage to perform actions like clicks or inputs.

These locators can be based on different things, like the HTML structure of the page or specific attributes of the elements.

Playwright supports several types of locators. CSS selectors are popular because they’re flexible and powerful, allowing testers to pinpoint elements by their style attributes.

XPath locators are another option, offering a way to find elements based on their position in the HTML document structure. Each type has its use cases, depending on what’s most reliable for identifying elements on a page.

The Need for Dynamic Element Locators

Static locators work well until they don’t. The web is a dynamic place, with web pages being updated and changed all the time.

When an element’s identifier changes – maybe its ID gets updated or its class name alters – a static locator can’t find it anymore. This leads to test failures, which can be a false alarm if the page is actually working as intended.

Dynamic locators shine in scenarios where the web page changes often or when elements are dynamically generated with different identifiers each time the page loads.

For instance, in a shopping cart, product listings might get unique IDs every time, making it hard for a static locator to keep track.

Dynamic locators adapt to these changes, making sure tests are reliable and accurate.

Implementing Dynamic Element Locators in Playwright

To tackle the challenges of web element identification, dynamic locator strategies come into play. These strategies involve using code to adaptively find elements based on patterns or conditions rather than fixed identifiers.

Basic Concepts

  • String Interpolation: This is a method where you construct a string (in this case, a locator) by embedding variable parts into a constant part. It’s like having a template that adjusts based on the data you give it.
  • Functions for Locator Value Generation: Sometimes, you need a more complex logic to identify an element. Writing functions allows you to generate locator values on the fly, considering the current state of the webpage or other dynamic data.

Step-by-Step Examples

Example 1: Using String Interpolation for Dynamic ID Handling

Imagine you have a user profile page where element IDs include the user’s unique ID, which changes for each user. A static locator would fail here, but with string interpolation, you can dynamically target these elements.

1. Identify the pattern in the element’s ID (e.g., user-{userId}-profile).

2. In your Playwright test, obtain or define the userId dynamically.

3. Construct the locator by embedding the userId into the template string: const userProfileLocator = \user-${userId}-profile`;`.

4. Use this dynamic locator in your Playwright actions.

Example 2: Creating Functions for Complex Locator Generation

Sometimes elements are not just identified by a simple ID change. You might need to find an element based on multiple conditions, like text content and class names that vary.

1. Define a function that generates a locator based on your conditions. For example, find a button by its dynamic text and class:
function dynamicButtonLocator(buttonText, buttonClass) {

  return `button.${buttonClass}:text(“${buttonText}”)`;


2. Use this function to generate a locator during your test, passing in the variable text and class names:
const locator = dynamicButtonLocator(‘Submit’, ‘dynamic-class’);

3. Use the generated locator in your Playwright test actions.

Through these strategies, testers can create more resilient tests that adapt to changes in the web application’s UI, making automated testing with Playwright even more powerful and reliable.

These dynamic approaches help keep tests green and accurate, providing confidence in the quality of the web application being tested.

LambdaTest: Elevating Playwright Tests with Cloud-Based Platform Support

In the ever-evolving landscape of web development and testing, keeping up with different browser versions and operating systems is a daunting task.

Here’s where LambdaTest comes into the picture, offering a cloud-based platform that supports Playwright automation.

LambdaTest allows testers to run their Playwright scripts across a vast selection of browser versions, including Chrome, Firefox, and Safari browser online and operating systems, without maintaining a lab of physical devices and virtual machines.

This capability is especially beneficial when working with dynamic element locators, as it enables testing under conditions that closely mimic real user environments.

LambdaTest supports Playwright, which offers significant advantages. One key benefit is scalability. Testers can run multiple tests in parallel across various browser and OS combinations, drastically reducing the time needed for extensive test suites.

This is particularly useful when implementing dynamic element locators, as it allows for rapid verification of locator strategies across different environments.

A standout feature of LambdaTest that enhances testing with dynamic locators is its real-time testing capability. This feature enables testers to interactively run and debug their Playwright scripts in real time, providing immediate feedback on the effectiveness of dynamic locator strategies.

Moreover, LambdaTest’s integrations with CI/CD pipelines facilitate the automatic triggering of Playwright tests, ensuring that dynamic locator tests are part of the regular build and release process, catching issues early.

Best Practices for Dynamic Locator Implementation

When implementing dynamic locators in Playwright, following best practices can significantly enhance test reliability and efficiency. Here are some tips to keep in mind:

1. Keep locators simple and robust: Aim for simplicity in your locator strategies to avoid brittle tests. Use the most stable features of an element, such as text content or specific attributes that are less likely to change over time.

2. Use fallback locators: Sometimes, even the best locator strategy might fail due to unforeseen changes. Implementing fallback strategies, where another locator is tried if the first one fails, can improve test reliability.

3. Validate locator effectiveness: Regularly review and test your locators against new versions of your web application. This ensures that they remain effective and adjust them as needed.

4. Prioritize locator testability: When designing your web application, work with developers to ensure elements are test-friendly. Attributes like data-testid can make elements easier to target reliably with dynamic locators.

Troubleshooting Common Issues

Implementing dynamic element locators is not without its challenges. Here are some common issues and their solutions:

1. Locators failing due to UI changes: Even with dynamic locators, significant UI overhauls can break tests. Regularly updating and reviewing tests to align with UI updates can mitigate this.

2. Complex locators slowing down tests: Overly complex locators can increase test execution time. Simplify locators where possible and use more direct paths to elements.

3. Difficulty in locating elements within dynamic content: When dealing with highly dynamic content, consider using Playwright’s waitForSelector or wait For Function methods to ensure elements are present before attempting interactions.


Dynamic locating of elements is at the very core of an effective automation solution using Playwright, helping to cater to the long-established “dynamic nature” challenge of modern web applications. All these strategies prove to work not just towards better accuracy but also evolve with the dynamically changing web.

These are the stakes put in place for a testing ecosystem with tools and environment in place, from executing locator strategies to refining them in a dynamic way across numerous browsers and operating systems. With such best practices, the test organization will manage to solidify their automation action plan for a more reliable and strengthened web app.

As testing right on the web itself comes up, the very concept of the flexibility and robustness it brings remains at the very core of keeping pace with the idea.

In fact, in the present scenario, testers are supposed to use innovation in this field and move towards a dynamic locator and to startups like LambdaTest, which are into this area with newer levels of detailed information not immediately available for users in most of the traditional testing tools.

Way Forward

We’ve journeyed through the realm of dynamic element locators and seen how they can significantly uplift your Playwright automation efforts. Now, it’s your turn to put this knowledge into action. Implement these strategies in your own Playwright scripts. Witness firsthand how dynamic locators can make your tests more resilient and adaptive to the ever-changing web environment.

Don’t stop there! Enhance your Playwright testing capabilities further by signing up for LambdaTest. Experience the power of cloud-based testing across a multitude of browser and operating system combinations.

With LambdaTest, you can scale your testing efforts, streamline your CI/CD pipeline with automated tests, and leverage real-time testing to debug and perfect your dynamic locator strategies. The path to robust, reliable web application testing is before you.

Implement dynamic element locators in your Playwright scripts and join the LambdaTest platform to unlock a new level of testing efficiency and effectiveness. Start today and elevate your automated testing to new heights!

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