does not pass args capability to geckodriver

🐛 Bug Report

I am unable to append options to the geckodriver args capability via the desired_capabilities parameter.

To Reproduce

I am running this:

#!/usr/bin/env python

from selenium.webdriver import Firefox, DesiredCapabilities
import time

capabilities = DesiredCapabilities.FIREFOX.copy()
capabilities['args'] = ["-headless"]

print(capabilities)

webdriver = Firefox(desired_capabilities=capabilities)
webdriver.get("https://google.com")

while 1:
    time.sleep(0.1)

Expected behavior

A headless instance visiting google.com, as I gather from the docs: the -headless string being one of the members of the args array should mandate that headlessness.

Actual behavior

A visible window.

Test script or set of commands reproducing this issue

Provided above.

Environment

OS: Linux x86_64 Browser: Firefox Browser version: Mozilla Firefox 88.0.1 Browser Driver version: geckodriver 0.29.0 Language Bindings version: Python’s selenium 3.141.0 package

Additional info

I have that other types of args are not passed either. For instance, capabilities['args'] = ["-profile", "<PATH-TO-EXISTING-PROFILE>"] does not result in geckodriver using that existing profile, as suggested by the docs that it should.

[AutomatedTester]

@AutomatedTester Incidentally, I’m aware that one can pass firefox_profile=<whatever> or options.profile=<whatever>, but this does not do wat I want: I have checked that both create copies of that profile to a temporary location. If I end the driver cleanly whatever they’ve gathered is wiped out.

For instance, if I delete the cookies.sqlite from <PROFILE> and then pass firefox_profile=<PROFILE> when building the driver, it will not leave behind a cookies.sqlite file in my original profile directory.

So: what I am after is a way to use a profile persistently with geckodriver. To save my life I cannot do this.

What you are after is going against how Selenium, and Geckodriver, do things in general. Selenium originally, and then geckodriver too, copy the profile so that if you pass it in that you get the same start point as always. We found that it was a major footgun to allow things to persist indefinitely as well as being a security issue if people share these profiles around.

If you want to get the resultant profile after running your automation code I suggest you do something like

from selenium.webdriver.firefox.options import Options
from selenium import webdriver
options = Options()
options.profile = "/path/to/profile"
driver = webdriver.Firefox(options=options)
# Do whatever you want
profile = driver.firefox_profile
# copy the profile somewhere
driver.quit()

The thing you’re trying to do is not how Selenium/Geckodriver was designed so you’re going to have to try be creative here.

[stuart-little]

@AutomatedTester Thank you: confirming that Selenium does not make this easy by default is at least a sanity check of sorts. I thought it was me missing some easy persistence switch.

As to being creative, yes, I figured I’d have to cobble something together… What I’ve settled on for now, since I’m specifically interested in cookies, is hard-linking the temp profile’s cookies.sqlite file to a location of my choosing. Then, when it exits, writes the cookies to that database, releases the lock and then deletes it, I have the copy.

Anyway, I think I can work with this. Thank you very much for all the help and the time you invested in this exchange.