[🐛 Bug]: Python logging not working correctly

[cgoldberg]

What happened?

I'm not sure if this is a bug or a documentation issue, but I am unable to get any logging working from the Python bindings using the logging instructions from the official docs.

According to the Python examples in the docs, DEBUG level logging to the console can be enabled with:

logger = logging.getLogger('selenium')
logger.setLevel(logging.DEBUG)

The following code should open Chrome and load a url, while displaying DEBUG level logs to the console:

import logging
from selenium import webdriver

logger = logging.getLogger('selenium')
logger.setLevel(logging.DEBUG)

with webdriver.Chrome() as driver:
    driver.get('https://example.com')

However, nothing is displayed to the console.

I can enable DEBUG logging globally for all modules, with:

logging.basicConfig(level=logging.DEBUG)

This works... The following code opens Chrome and loads a url, while displaying DEBUG level logs to the console:

import logging
from selenium import webdriver

logging.basicConfig(level=logging.DEBUG)

with webdriver.Chrome() as driver:
    driver.get('https://example.com')

I get the full set of logs doing that... but this isn't ideal since it enables logging for every module and doesn't allow more fine-grained adjustments.

So why does the first example not display any logs? Either there is something wrong with logging in selenium, or the docs are not correct (or I have somehow misinterpreted them).

How can we reproduce the issue?

See description above.

Relevant log output

N/A

Operating System

All OS

Selenium version

Python Selenium 4.29.0

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

All browsers

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

All drivers

Are you using Selenium Grid?

No

[github-actions]

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

---

Info for maintainers

Triage this issue by using labels.

If information is missing, add a helpful comment and then I-issue-template label.

If the issue is a question, add the I-question label.

If the issue is valid but there is no time to troubleshoot it, consider adding the help wanted label.

If the issue requires changes or fixes from an external project (e.g., ChromeDriver, GeckoDriver, MSEdgeDriver, W3C), add the applicable G-* label, and it will provide the correct link and auto-close the issue.

After troubleshooting the issue, please add the R-awaiting answer label.

Thank you!

[cgoldberg]

I will investigate this more when I get a chance, but if anyone has any tips... please comment.

[navin772]

@cgoldberg we need to add a stream handler to get the log output, like this:

import logging
from selenium import webdriver

logger = logging.getLogger('selenium')
logger.setLevel(logging.DEBUG)

handler = logging.StreamHandler()
logger.addHandler(handler)

with webdriver.Chrome() as driver:
    driver.get('https://example.com')

Using this, I am getting the logs.

I am not sure if we should add a default handler to selenium as it is not advised here (refer the Note's).

But, we should be updating the docs.

[cgoldberg]

@navin772

Thanks! I will put in a PR for updating the docs. I'll leave this issue open until it lands.

(the Python logging library always makes my head explode 🤯)

[github-actions]

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