selenium.common.exceptions.StaleElementReferenceException: Message: stale element reference: element is not attached to the page document

Question

I use Python Beautiful Soup to move through DOM elements and Selenium to open page in chrome and ActionChains to scroll in page. It worked fine but the website changed something and now I run into two kinds of error on the way it worked before and on a new way as a possible solution.

Old solution:

submit_button = driver.find_element_by_name('quantity')

elementList = submit_button.find_elements_by_tag_name("option")

elementList[int(column)-1].click()

Old Error:

Traceback (most recent call last):
  File "C:/Users/Felix_P/PycharmProjects/Price_Tool/Combination_14_6_2016.py", line 205, in <module>
    elementList[int(column)-1].click()
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\remote\webelement.py", line 75, in click
    self._execute(Command.CLICK_ELEMENT)
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\remote\webelement.py", line 469, in _execute
    return self._parent.execute(command, params)
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 201, in execute
    self.error_handler.check_response(response)
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\remote\errorhandler.py", line 193, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.ElementNotVisibleException: Message: element not visible: Element is not currently visible and may not be manipulated
  (Session info: chrome=51.0.2704.103)
  (Driver info: chromedriver=2.21.371459 (36d3d07f660ff2bc1bf28a75d1cdabed0983e7c4),platform=Windows NT 6.1 SP1 x86_64)

New Solution:

submit_button = driver.find_element_by_name('quantity')

elementList = submit_button.find_elements_by_tag_name("option")

actions.move_to_element(elementList[int(column)-1]).click().perform()

New Error:

Traceback (most recent call last):
  File "C:/Users/Felix_P/PycharmProjects/Price_Tool/Combination_14_6_2016.py", line 201, in <module>
    actions.move_to_element(elementList[int(column)-1]).click().perform()
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\common\action_chains.py", line 72, in perform
    action()
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\common\action_chains.py", line 217, in <lambda>
    self._driver.execute(Command.MOVE_TO, {'element': to_element.id}))
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 201, in execute
    self.error_handler.check_response(response)
  File "C:\Python35-32\lib\site-packages\selenium\webdriver\remote\errorhandler.py", line 193, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.StaleElementReferenceException: Message: stale element reference: element is not attached to the page document
  (Session info: chrome=51.0.2704.103)
  (Driver info: chromedriver=2.21.371459 (36d3d07f660ff2bc1bf28a75d1cdabed0983e7c4),platform=Windows NT 6.1 SP1 x86_64)

Answer 1

From you error stack, it shows that your reserved reference were stale. This usually is caused by page refresh or enven a page event.

So you have to get the element again before access it.

---

For example,

elements = driver.find_elements_by_tag_name('tagname'))
for element in elements:
    driver.get(element.get_attribute('url'))

will cause

selenium.common.exceptions.StaleElementReferenceException

Answer 2

I think I see the problem. If you show all of your code, it will probably show that last line is within a for loop that is navigating away from the page, then coming back to the same page (or some ajax has refreshed that set of options on the page). The problem is that the page has reloaded, so the target element from elementList doesn't exist any longer.

You'll need to define your elementList by keeping track of a list of something like value on the option, then use find_element within the loop to find each unique option element again.