UnableToCaptureScreenException in Selenium: How to Handle?

Hari Mahesh

Exceptions in Selenium are mainly used to handle and manage error scenarios and unexpected situations while executing test automation. Exceptions help detect and address errors, improve test reliability, and provide valuable diagnostic information.

One such Selenium exception that we come across is UnableToCaptureScreenException. Let’s review the exception, its root cause, and how to resolve it in detail.

UnableToCaptureScreenException – Root Cause

UnableToCaptureScreenException occurs when Selenium cannot capture the screenshot of the current page. So, for some reason, when we try to capture the screenshot of the web page, and it fails, this exception is thrown. There can be many reasons this exception can be thrown; let’s dive into those.

• Browser or WebDriver Issues: If there is any issue with the web browser or the webDriver, then this exception can be raised. Issues can also be with the browser’s rendering engine, or there can be a limitation of WebDriver, too.
• Lack of Permission: In many cases, the exception is thrown when the web browser or WebDriver doesn’t have enough permissions to capture screenshots. This can happen when the automation runs, especially in a restricted or headless environment.

  from selenium import webdriver
  driver = webdriver.Chrome()
  driver.get("https://www.example.com")
  
  try:
    driver.save_screenshot("C:\\screenshot.png") # Permission denied error
  except Exception as e:
    print("Unable to capture screenshot:", e)

• Resource Exhaustion: You can see this exception thrown if the test automation runs on a machine with low system resources, such as memory or disk space.
• Timing Issues: This exception will be thrown when the screen capture is not provided with enough time gap during page transition or the browser is unexpected.
• WebDriver Configuration: An outdated or incompatible WebDriver executable can create an issue with screenshot capture, leading to this exception.
• Incorrect File Path: Providing an inaccurate or invalid file path can raise the exception.

  from selenium import webdriver
  driver = webdriver.Chrome()
  driver.get("https://www.example.com")
  
  try:
    driver.save_screenshot("screenshot.png") # Invalid file path
  except Exception as e:
    print("Unable to capture screenshot:", e)

UnableToCaptureScreenException – How to Resolve?

Try using the below methods to avoid UnableToCaptureScreenException in Selenium scripts:

Ensure Proper Permission

from selenium import webdriver
driver = webdriver.Chrome()
driver.get("https://www.example.com")

try:
  driver.save_screenshot("C:\\screenshot.png") # Ensure WebDriver has write permissions
except Exception as e:
  print("Unable to capture screenshot:", e)

Ensure the script user has write access to the directory where the screenshot is being saved.

Use a Valid File Path

from selenium import webdriver
driver = webdriver.Chrome()
driver.get("https://www.example.com")

try:
  driver.save_screenshot("screenshot.png") # Provide a valid file path
except Exception as e:
  print("Unable to capture screenshot:", e)

Check Disk Space

from selenium import webdriver
driver = webdriver.Chrome(executable_path="path_to_valid_chromedriver.exe")
driver.get("https://www.example.com")

try:
  driver.save_screenshot("screenshot.png") # Use a valid WebDriver
except Exception as e:
  print("Unable to capture screenshot:", e)

WebDriver Compatibility

from selenium import webdriver
driver = webdriver.Chrome(executable_path="path_to_valid_chromedriver.exe")
driver.get("https://www.example.com")

try:
  driver.save_screenshot("screenshot.png") # Use a valid WebDriver
except Exception as e:
  print("Unable to capture screenshot:", e)

Exception Handling

from selenium import webdriver
driver = webdriver.Chrome()
driver.get("https://www.example.com")

try:
  driver.save_screenshot("screenshot.png")
except Exception as e:
  print("Unable to capture screenshot:", e)
  # Implement custom error handling or logging here

Logging and Debugging

from selenium import webdriver
driver = webdriver.Chrome()
driver.get("https://www.example.com")

try:
  driver.save_screenshot("screenshot.png")
except Exception as e:
  print("Unable to capture screenshot:", e)
  # Log additional information for debugging
  with open("error_log.txt", "a") as log_file:
    log_file.write(f"Error: {str(e)}\n")

An Intelligent and Practical Way of Avoiding Exceptions

For long, Selenium has been the widely used web automation tool. However, as customer requirements become more aggressive, organizations have to change how they deliver the products or services. Development models like Agile XP came in place to make that effective. But Selenium couldn’t catch up with the fast pace. Anyone who needs to use the Selenium automation tool needs to create the framework from scratch. Everything needs to be written in programming languages, like reports, screenshots, logs, and integrations. So, the organization needs to spend an initial few months making the framework mature. As this aligns differently with the company’s goals, Selenium faded away from being a preferable choice. There are many reasons why Selenium is not a good choice for automation.

On the other hand, the intelligent automation testing tool testRigor stands out due to its valuable and user-friendly features. Using testRigor, we don’t have to worry about setting up the framework or the integrations, as it’s packed with everything required to start testing. Let’s look at a few features of testRigor.

• Real-Time Logs: When we execute testRigor, we can see the logs in real-time. When we say as logs, it means the real-time screenshot of each test step. We don’t have to wait till the whole test suite finishes executing. That’s one of the main advantages of testRigor. Not just that, testRigor also provides a video record of the test case execution. Also, it gives a detailed log if any test log is failed. All this is done without any input from our side. So just trigger the test case and sit back; testRigor does it for you automatically.
• Seamless Integrations: testRigor provides seamless integration with leading test case management tools, ticketing tools, CI platform tools, and infrastructure-providing tools.
• No Worry about Coding: Using testRigor, we can create test cases in parsed English using generative AI and NLP. So, the QA team doesn’t need to have coding skills. They can focus on what they do best, i.e., creating robust tests and achieving excellent test coverage. Anyone in the team can use testRigor to generate test scripts and execute them efficiently, irrespective of their technical skills.

So what is mentioned above is just the tip of the iceberg. You can go through the extensive features of testRigor here.

Summing Up

Customer expectations are increasing daily, and the market is getting more aggressive. To be on par with the development, QA must be more thoughtful about how it signs off the application. Why waste time debugging and troubleshooting Selenium exceptions when you have modern tools to help you?

Using innovative and intelligent tools like testRigor makes the quality check easier for your team, saving enormous time and effort in test creation, execution, and maintenance. testRigor helps you achieve quick and higher ROI within your software testing budget.

“We spent so much time on maintenance when using Selenium, and we spend nearly zero time with maintenance using testRigor.”

Keith Powe VP Of Engineering - IDT