Python Selenium Detect when the browser is closed

Question

Right now, I use this as a way to detect when the user closes the browser:

while True:
    try:
        # do stuff
    except WebDriverException:
        print 'User closed the browser'
        exit()

But I found out that it is very unreliable and a very bad solution since WebDriverException catches a lot of exception (if not all) and most of them are not due to the user closing the browser.

My question is: How to detect when the user closes the browser?

Answer 1

I would suggest using:

>>> driver.get_log('driver')
[{'level': 'WARNING', 'message': 'Unable to evaluate script: disconnected: not connected to DevTools\n', 'timestamp': 1535095164185}]

since driver logs this whenever user closes browser window and this seems the most pythonic solution.

So you can do something like this:

DISCONNECTED_MSG = 'Unable to evaluate script: disconnected: not connected to DevTools\n'

while True:
    if driver.get_log('driver')[-1]['message'] == DISCONNECTED_MSG:
        print 'Browser window closed by user'
    time.sleep(1)

If you're interested you can find documentation here.

I am using chromedriver 2.41 and Chrome 68.

Answer 2

Similar to Federico Rubbis answer, this worked for me:

import selenium
from selenium import webdriver
browser = webdriver.Firefox()

# Now wait if someone closes the window
while True:
    try:
        _ = browser.window_handles
    except selenium.common.exceptions.InvalidSessionIdException as e:
        break
    time.sleep(1)

# ... Put code here to be executed when the window is closed

Probably not a solution that is stable across versions of selenium.
EDIT: Not even stable across running from different environments. Ugly fix: Use BaseException instead of selenium.common.exceptions.InvalidSessionIdException .

Answer 3

this worked for me:

#libraries
from selenium.webdriver.chrome.options import Options
from selenium import webdriver

#open browser in kiosk mode
def openBrowser():
    chrome_options = Options()
    chrome_options.add_argument("--kiosk")
    path = '"C:\\Users\\an8799\Documents\Repositorio\\testes\chromedriver.exe"'
    driver = webdriver.Chrome(path, chrome_options=chrome_options)
    driver.get('https://google.com.br')
    return driver

#verify if browser is opened.
def uptdateBrowser(browser):
    try:
       _ = browser.window_handles
       print('windon opened')
       return 0, 0
    except:
        newbrowser = openBrowser()
        print('window closed')
        return 1, newbrowser

#start browser verification loop
def main():
    browser = openBrowser()
    while(True):
        flagNew, newB = uptdateBrowser(browser)
        if flagNew == 1:
            browser = newB
#call main loop
if __name__ == '__main__':
    main()

Answer 4

Although Federico Rubbi answer works, it doesn't work always. When the user closes the webdriver, the driver.get_log('driver') will raise an excepton.

The following function works quite well, as far as i tested it (Chrome version 110). It also works with undetected chromedriver.

from selenium.webdriver.chrome.options import Options
from selenium import webdriver
from urllib3.exceptions import NewConnectionError, MaxRetryError


def is_driver_open(driver: webdriver.Chrome) -> bool:
    """
    Checks if the webdriver is still open by checking the logs.
    """
    disconnected_msg = 'Unable to evaluate script: disconnected: not connected to DevTools\n'
    disc_msg = "Unable to evaluate script: no such window: target window already closed" \
               "\nfrom unknown error: web view not found\n"
    message_listener = "subscribing a listener to the already connected DevToolsClient"
    if driver:
        try:
            log = driver.get_log('driver')
        except (ConnectionRefusedError, MaxRetryError, NewConnectionError):
            # The webdriver is closed, the connection to the Chrome is refused.
            return False
        print(f"is_driver_open(): log: {log}")
        if len(log) != 0:  # This does not catch all other messages.
            if log[-1]['message'] in (disconnected_msg, disc_msg):
                print("Webdriver is closed")
                return False
            elif message_listener in log[-1]['message']:
                # It's not closed.
                return True
            else:
                return True
        else:  # No errors, return True.
            return True


if __name__ == "__main__":
    options = Options()
    driver = webdriver.Chrome(options=options)
    print(f"Is driver open: {is_driver_open(driver)}")
    driver.quit()
    print(f"Is driver open: {is_driver_open(driver)}")