Explicit Wait in Selenium

Introduction

In web automation testing, user interactions with web pages such as button clicks, form submissions, and page navigation are automated. The page might not have fully loaded or the element might not be there when the script tries to communicate with it, and these interactions can take some time to finish. In such circumstances, the test script might malfunction and produce false results.

Selenium uses waits to make sure that the script waits for a certain condition to be satisfied before moving on to the next step in the test case to solve this problem. Explicit wait in Selenium is one way to solve this issue.

Why Do We Need Waits In Selenium?

To guarantee that the test scripts are trustworthy and yield accurate results, waits are crucial in` Selenium automated testing. Explicit wait in Selenium is one way to handle the situation. There are several reasons why delays are necessary:

• Page Load Time: Web pages can take some time to load, and during that time, the script may attempt to interact with a loading element. Waits make sure that the script doesn't interact with any page elements until the page has fully loaded.
• Network Latency: Due to network latency, online pages may take longer to load, which may lead the script to attempt to interact with a loading element. Waits make sure that before interacting with an element, the script waits for both the page to load and the element to appear.
• Asynchronous Operations: Asynchronous operations, like those used by AJAX in many web applications, can delay the loading of page items. Waits make sure that the script does not interact with an element until it has loaded.
• Unpredictable User Input: User input can occasionally be unpredictable, and the script may be unable to interact with a certain element until a certain circumstance is present. Waits make sure that before interacting with the element, the script waits for the condition to be satisfied.

Selenium Web Driver Waits

Selenium waits are an essential tool` for automation testing in Selenium. They help ensure that the test scripts are reliable and produce accurate results by waiting for specific conditions to be met before proceeding. There are two types of waits in Selenium.

Implicit Wait

An implicit wait is a way to tell Selenium to wait for a specific amount of time before throwing a NoSuchElementException. The implicit wait is applied globally to all elements in the test script. If the script tries to interact with an element that has not loaded yet, Selenium waits for the implicit wait time before throwing a NoSuchElementException.

The implicit wait is set using the driver.implicitly_wait() function, which takes a timeout value in seconds:

Explicit Wait

An explicit wait in Selenium is a way to tell Selenium to wait for a specific condition to be met before proceeding to the next step in the test case. The explicit wait is applied to a specific element or a group of elements in the test script.

Explicit waits in Selenium are implemented using the WebDriverWait class, which provides a set of expected conditions that can be used to wait for a specific condition to be met before proceeding to the next step in the test case.

Explicit Wait In Selenium

Explicit waits in Selenium are used when we need to wait for a specific condition to be met before proceeding with the test script. For instance, we could wish to hold off on the next test case step until an element is clickable or visible.

Contrary to implicit waits, which wait for a fixed period before continuing, explicit waits in Selenium offer a more precise way of waiting for a particular condition to be met.

Explicit Wait syntax

The syntax for an explicit wait in Selenium is as follows:

This code snippet creates an instance of the WebDriverWait class, passes the driver instance and a timeout value, and waits for a specific condition to be met using an expected condition provided by the expected_conditions module.

Explanation of Code

Let's break down the code above for Explicit Wait in Selenium and explain each step in more detail.

In the first step, we import the necessary modules, including By and WebDriverWait from the selenium.webdriver.common.by and selenium.webdriver.support.ui modules, respectively. We also import the expected_conditions module as EC.

We then create a driver instance using the webdriver. Chrome() method, which creates a ChromeDriver instance.

In the next step, we navigate to a web page using the get() method of the driver instance.

Explanation

To implement an explicit wait in Selenium, we create an instance of the WebDriverWait class and pass it to the driver instance and a timeout value of 10 seconds. We then call the element_to_be_clickable() expected condition from the expected_conditions module and pass it a tuple of (By. ID, "element_id"), which specifies the locator strategy and the element ID.

The until() method of the WebDriverWait class waits until the expected condition is met or the timeout value is exceeded. If the expected condition is not met within the timeout value, a TimeoutException is raised.

If the expected condition is met within the timeout value, the until() method returns the element that met the condition, and we can store it in a variable for further use in the test script.