[🐛 Bug]: Removal of headless option

[yanniszark]

What happened?

Was using the headless field in Options, which was removed.
Code was failing without any clue as to why.
Please consider failing loudly (for example, by keeping the property method and throwing an error).

How can we reproduce the issue?

Set `headless` in `Options` for Chrome.

Relevant log output

session not created: Chrome failed to start: exited normally.
  (session not created: DevToolsActivePort file doesn't exist)
  (The process started from chrome location /opt/google/chrome/google-chrome is no longer running, so ChromeDriver is assuming that Chrome has crashed.)
Stacktrace:
#0 0x559a7afac6b3 <unknown>
#1 0x559a7ac821e7 <unknown>
#2 0x559a7acb5526 <unknown>
#3 0x559a7acb169c <unknown>
#4 0x559a7acf423a <unknown>
#5 0x559a7aceae93 <unknown>
#6 0x559a7acbd934 <unknown>
#7 0x559a7acbe71e <unknown>
#8 0x559a7af71cb8 <unknown>
#9 0x559a7af75bf0 <unknown>
#10 0x559a7af8019c <unknown>
#11 0x559a7af76808 <unknown>
#12 0x559a7af4327f <unknown>
#13 0x559a7af9ae88 <unknown>
#14 0x559a7af9b059 <unknown>
#15 0x559a7afab843 <unknown>
#16 0x7f0cbfb7a609 start_thread
.
Stack Trace: Traceback (most recent call last):
  File "projects/dev-container/scripts/extend_cloudlab_experiments.py", line 138, in main
    extend_experiments(username, password, args.notify_slack)
  File "projects/dev-container/scripts/extend_cloudlab_experiments.py", line 77, in extend_experiments
    cloudlab_client = CloudlabClient()
  File "/usr/local/lib/python3.8/dist-packages/cloudlab_client/client.py", line 104, in __init__
    driver = webdriver.Chrome(options=options)
  File "/usr/local/lib/python3.8/dist-packages/selenium/webdriver/chrome/webdriver.py", line 45, in __init__
    super().__init__(
  File "/usr/local/lib/python3.8/dist-packages/selenium/webdriver/chromium/webdriver.py", line 56, in __init__
    super().__init__(
  File "/usr/local/lib/python3.8/dist-packages/selenium/webdriver/remote/webdriver.py", line 205, in __init__
    self.start_session(capabilities)
  File "/usr/local/lib/python3.8/dist-packages/selenium/webdriver/remote/webdriver.py", line 289, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
  File "/usr/local/lib/python3.8/dist-packages/selenium/webdriver/remote/webdriver.py", line 344, in execute
    self.error_handler.check_response(response)
  File "/usr/local/lib/python3.8/dist-packages/selenium/webdriver/remote/errorhandler.py", line 229, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.SessionNotCreatedException: Message: session not created: Chrome failed to start: exited normally.
  (session not created: DevToolsActivePort file doesn't exist)
  (The process started from chrome location /opt/google/chrome/google-chrome is no longer running, so ChromeDriver is assuming that Chrome has crashed.)
Stacktrace:
#0 0x559a7afac6b3 <unknown>
#1 0x559a7ac821e7 <unknown>
#2 0x559a7acb5526 <unknown>
#3 0x559a7acb169c <unknown>
#4 0x559a7acf423a <unknown>
#5 0x559a7aceae93 <unknown>
#6 0x559a7acbd934 <unknown>
#7 0x559a7acbe71e <unknown>
#8 0x559a7af71cb8 <unknown>
#9 0x559a7af75bf0 <unknown>
#10 0x559a7af8019c <unknown>
#11 0x559a7af76808 <unknown>
#12 0x559a7af4327f <unknown>
#13 0x559a7af9ae88 <unknown>
#14 0x559a7af9b059 <unknown>
#15 0x559a7afab843 <unknown>
#16 0x7f0cbfb7a609 start_thread

Operating System

Ubuntu

Selenium version

4.13

What are the browser(s) and version(s) where you see this issue?

Latest Chrome

What are the browser driver(s) and version(s) where you see this issue?

Latest Version

Are you using Selenium Grid?

No

[github-actions]

@yanniszark, thank you for creating this issue. We will troubleshoot it as soon as we can.

---

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Thank you!

[titusfortner]

It's frustrating to get unexpected behavior. Python is interesting in how it lets you assign anything to anything regardless of whether it does anything. DevToolsActivePort bug is known and Google is working on it.

As for headless, we threw deprecation warnings that it was going to be removed for most of the past year and wrote a blog post explaining why.

At the same time, we don't want to maintain code that just throws error messages about what all things we don't support. It should be obvious that you aren't getting a headless session and hopefully easy to find out why with a Google search or a code inspection.

[yanniszark]

As for headless, we threw deprecation warnings that it was going to be removed for most of the past year and wrote a blog post explaining why.

That's great practice. In this case, I missed it since my code is running in an automated and pulling the latest selenium.

It should be obvious that you aren't getting a headless session and hopefully easy to find out why with a Google search or a code inspection.

Neither is obvious unfortunately. Googling / ChatGPTing the error wasn't very helpful (hopefully now it is, since Google will index this issue).

I would propose adding a third phase to your deprecation plan, which is to throw deprecation errors (not warnings).
I understand this is an open-source project with limited resources, so this is just my honest feedback.
Thanks for your effort, this is a great piece of software.

[titusfortner]

"DevToolsActivePort not found" bug fix: https://bugs.chromium.org/p/chromedriver/issues/detail?id=4403#c35

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.