Explicit waits in Selenium Python

Selenium Python is one of the great tools for testing automation. These days most web apps are using AJAX techniques. When the browser loads a page, the elements within that page may load at different time intervals.

This makes locating elements difficult, if an element is not yet present in the DOM, a locate function will raise an ElementNotVisibleException exception. Using waits, we can solve this issue.

• Waiting provides some slack between actions performed - mostly locating an element or any other operation with the element.
• Selenium Webdriver provides two types of waits - implicit & explicit. This article revolves around Explicit wait in Selenium Python.

What is Explicit Waits?

An explicit wait is a code you define to wait for a certain condition to occur before proceeding further in the code. The extreme case is time.sleep(), which sets the condition to an exact waiting period. There are some convenience methods provided that help you write code that will wait only as long as required. Explicit waits are achieved by using the webdriverWait class in combination with expected_conditions.

Let's consider an example

Explanation of Code

• This waits up to 10 seconds before throwing a TimeoutException unless it finds the element to return within 10 seconds.
• WebDriverWait by default calls the ExpectedCondition every 500 milliseconds until it returns successfully.

Expected Conditions

There are some common conditions that are frequently of use when automating web browsers. For example, presence_of_element_located, title_is, ad so on.

One can check entire methods from here - Convenience Methods and some of them are follows

• title_is
• title_contains
• presence_of_element_located
• visibility_of_element_located
• visibility_of
• presence_of_all_elements_located
• element_located_to_be_selected
• element_selection_state_to_be
• element_located_selection_state_to_be
• alert_is_present

How to create an Explicit wait in Selenium Python?

• Explicit wait as defined would be the combination of WebDriverWait and Expected conditions.
• Let's implement this on https://www.geeksforgeeks.org/ and wait 10 seconds before locating an element.

Output

First it opens https://www.geeksforgeeks.org/ and then finds Courses link.

It clicks on courses links and is redirected to https://www.geeksforgeeks.org/ .

Conclusion

Explicit waits in Selenium Python offer main control over waiting for elements by automation. By combining WebDriverWait and ExpectedConditions, you can define specific conditions and a timeout to ensure reliable test automation for betterment purpose.