WebDriverException: Message: invalid argument: can't kill an exited process with GeckoDriver, Selenium and Python on RaspberryPi3

Question

Server: Raspberry Pi 3
OS: Dietpi - version 159
Geckodriver version: 0.22 for arm
Firefox version: 52.9.0
Python version: 3.5
Selenium version: 3.14.1

Gecko is executable, and is located in /usr/local/bin/

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.webdriver.firefox.options import Options
import time



options = Options()
options.set_headless(headless=True)
driver = webdriver.Firefox(firefox_options=options)

print('Need your login credential')
username = input('What is your username?:\n')
password = input('What is your password?:\n')
...
...

Output:

root@RPi3:~# python3.5 ITE-bot.py 
Traceback (most recent call last):
  File "ITE-bot.py", line 12, in <module>
    driver = webdriver.Firefox(firefox_options=options)
  File "/usr/local/lib/python3.5/dist-packages/selenium/webdriver/firefox/webdriver.py", line 174, in __init__
    keep_alive=True)
  File "/usr/local/lib/python3.5/dist-packages/selenium/webdriver/remote/webdriver.py", line 157, in __init__
    self.start_session(capabilities, browser_profile)
  File "/usr/local/lib/python3.5/dist-packages/selenium/webdriver/remote/webdriver.py", line 252, in start_session
    response = self.execute(Command.NEW_SESSION, parameters)
  File "/usr/local/lib/python3.5/dist-packages/selenium/webdriver/remote/webdriver.py", line 321, in execute
    self.error_handler.check_response(response)
  File "/usr/local/lib/python3.5/dist-packages/selenium/webdriver/remote/errorhandler.py", line 242, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: invalid argument: can't kill an exited process

Any idea what is wrong? I've tried google without luck.

Answer 1

This error message...

selenium.common.exceptions.WebDriverException: Message: invalid argument: can't kill an exited process

...implies that the GeckoDriver was unable to initiate/spawn a new WebBrowsing Session i.e. Firefox Browser session.

Your main issue is the incompatibility between the version of the binaries you are using as follows:

• Your GeckoDriver version is 0.22.0.

• Release Notes of GeckoDriver v0.21.0 (2018-06-15) clearly mentions the following:

  • Firefox 57 (and greater)

  • Selenium 3.11 (and greater)

• Your Firefox version is 52.9.0.

So there is a clear mismatch between GeckoDriver v0.22.0 and the Firefox Browser v57

Solution

• Upgrade GeckoDriver to GeckoDriver v0.22.0 level.
• GeckoDriver is present in the specified location.
• GeckoDriver is having executable permission for non-root users.
• Upgrade Firefox version to Firefox v62.0.2 levels.
• Clean your Project Workspace through your IDE and Rebuild your project with required dependencies only.
• If your base Web Client version is too old, then uninstall it through Revo Uninstaller and install a recent GA and released version of Web Client.
• Execute your Selenium Test as a non-root user.

Answer 2

If you are running Firefox on a system with no display, make sure you use headless mode.

from selenium import webdriver
from selenium.webdriver.firefox.options import Options

options = Options()
options.headless = True
driver = webdriver.Firefox(options=options)

Also, make sure you have compatible versions of Firefox, Selenium, and Geckodriver: https://firefox-source-docs.mozilla.org/testing/geckodriver/geckodriver/Support.html

Answer 3

Yes checked Start Xvfb before the build can fix the problem, but if you have a job like a pipeline or multibranch pipeline this option is not visible. In the node of your Selenium grid that you go to execute the test you need:

1- Install Xvfb: apt install xvfb

2- Execute Xvfb: /usr/bin/Xvfb :99 -ac -screen 0 1024x768x8 & export DISPLAY=":99"

3- Rerun your node, for example: java -jar selenium.jar -role node -hub http://#.#.#.#:4444/grid/register -capabilities browserName=firefox,plataform=linux -host #.#.#.# -port 1991

Answer 4

I was on headless mode, using correct versions of everything, and the only way to get out of this error message was not to execute the selenium test as root

Answer 5

I used:

• VS Code
• Linunx/Ubuntu:18.10
• Nightwatch.js

My problem was that I tried to run Nightwatch (which automatically starts GeckoDriver) from the VS Code terminal.

Answer 6

I was able to fix this by running my tests with Xvfb. I was running them on a remote server.

I was using Jenkins so I checked the box that looked like this:

Credit to https://www.obeythetestinggoat.com/book/chapter_CI.html