Web Scraping Using Selenium - Explicit Wait for Presence of Any Elements

Selenium Wait - Explicit Wait For Presence of Any Elements

Waiting in selenium can be done in different ways. In this tutorial, we will use the explicit wait functionality for presence of any elements given a locator. This is a way to check if the elements already load.

But before that, please make sure you have read the first blog on this series to do the prerequisites.

Selenium Explicit Wait For Presence of Any Elements Given a Locator

1. Create a file seleniumwaitpresenceall.py and paste the following codes

   from selenium import webdriver
   from selenium.webdriver.common.by import By
   from selenium.webdriver.support.ui import WebDriverWait
   from selenium.webdriver.support import expected_conditions as EC
   from selenium.common.exceptions import TimeoutException
   from datetime import datetime
   

   The codes above imports the required library that we will use.
2. Add this line

   driver = webdriver.Firefox(executable_path="geckodriver.exe")
   

   The code above will create a webdriver instance for Firefox.
3. Add this line

   driver.get("https://slackingslacker.github.io/seleniumindex")
   

   The line will got to the website (https://slackingslacker.github.io/seleniumindex).
4. Add this function as is

   def wait_for_the_elements(wait_time: int, el_name: str):
       try:
           print("[{}] Finding element {}".format(str(datetime.now()), el_name))
           WebDriverWait(driver, wait_time).until(
               EC.presence_of_all_elements_located((By.TAG_NAME, el_name))
           )
           print("[{}] Element found".format(str(datetime.now())))
       except TimeoutException as e:
           print("[{}] Element did not load".format(str(datetime.now())))
   

   This method will wait for the any element given a locator to load at a given waiting time. It will print a message if any element loaded or not.
5. Add this line

   wait_for_the_elements(3, "nav")
   

   This line will call the method we created and will display Element found.
6. Add this line

   wait_for_the_elements(6, "table")
   

   This line will call the method we created and wait for 6 seconds until it gives an error.
7. Add this line

   wait_for_the_elements(9, "ul")
   

   Again will call the method with a non existing element this time it is 9 seconds.
8. Add this line

   driver.close()
   

   The line will close the webdriver as well as the browser.
9. Run the seleniumwaitpresenceall.py. It should do the following:
   • Open the firefox browser
   • Browser goes to https://slackingslacker.github.io/seleniumindex
   • Call the Method 3 times which prints messages in the console
   • Closes the browser

 

Program Sample Output

[2020-06-01 01:02:57.360303] Finding element nav
[2020-06-01 01:02:57.375942] Element found
[2020-06-01 01:02:57.375942] Finding element table
[2020-06-01 01:03:03.456108] Element did not load
[2020-06-01 01:03:03.456108] Finding element ul
[2020-06-01 01:03:12.497395] Element did not load

Output explanations

1. The code looks for any element given the tag nav
2. The code found the element
3. The code looks for any element given the tag table
4. The code does not find the element within 6 seconds
5. The code looks for any element given the tag ul
6. The code does not find the element within 9 seconds

As you may have noticed that the waiting time varies to what you have supplied to the WebDriverWait class.

 

Final Selenium Code

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.common.exceptions import TimeoutException
from datetime import datetime

driver = webdriver.Firefox(executable_path="geckodriver.exe")
driver.get("https://slackingslacker.github.io/seleniumindex")

def wait_for_the_elements(wait_time: int, el_name: str):
    try:
        print("[{}] Finding element {}".format(str(datetime.now()), el_name))
        WebDriverWait(driver, wait_time).until(
            EC.presence_of_all_elements_located((By.TAG_NAME, el_name))
        )
        print("[{}] Element found".format(str(datetime.now())))
    except TimeoutException as e:
        print("[{}] Element did not load".format(str(datetime.now())))

wait_for_the_elements(3, "nav")
wait_for_the_elements(6, "table")
wait_for_the_elements(9, "ul")
driver.close()

 

Conclusion

Waiting time in selenium can be set to wait for any element given a locator.