Test Automation - How To Use Custom User Agent In Selenium Python Or Playwright Python To Avoid Security Bots

Introduction

In web automation, the challenges posed by security bots have become increasingly prevalent. This article aims to guide you through a strategic approach – using custom user agents in Selenium Python and Playwright Python – to navigate the hurdles these security measures present. Security bots are designed to detect and later prevent automated activities, impacting the effectiveness of test automation efforts.

Using a unique user agent allows automated tests to interact with websites after aligning with security requirements to circumvent bot detection, whether internal or from third-party API providers.

Implementing the Solution

Selenium

chrome_options.add_argument(f"user-agent={Constants.AUTOMATION_USER_AGENT}")

• chrome_options: This variable typically holds an instance of ChromeOptions, which is a class in Selenium used to customize the behavior of the Chrome browser when it’s launched via Selenium.
• add_argument: This method is used to add command-line arguments to the options. In this case, it adds a user-agent argument.

link to the project - with complete code examples.

Playwright

@pytest.fixture(scope="session")
def browser_context_args(browser_context_args):
    return {
        **browser_context_args,
        "user_agent": Constants.AUTOMATION_USER_AGENT,
    }

This Pytest fixture is designed to set up the arguments for a Playwright browser context, specifically in the context of a session. Let’s break down the code:

@pytest.fixture(scope=“session”): This is a Pytest decorator that defines a fixture, which is essentially a way to set up or configure resources before running tests. The scope=“session” parameter means that this fixture will be executed once per test session.

• browser_context_args: This is a parameter that represents the default browser context arguments. It’s a common practice to pass existing context arguments to the fixture to extend or modify them.
• The return statement line combines the existing browser context arguments with an additional argument for the user agent. It uses the ** (dictionary unpacking) syntax to merge dictionaries. The user agent value is used to set the user agent for Playwright browser context.

link to the project - with complete code examples.

In conclusion

Adapting user agents elevates web automation, ensuring seamless security compliance.

Happy testing!