Hey everyone, I’m stuck with a Selenium issue. I’m trying to hook up to a headless Chrome browser that’s already running. It works fine with a regular Chrome instance using the remote debugging port. But when I try it with headless Chrome, I get this error:
selenium.common.exceptions.WebDriverException: Message: unknown error: cannot connect to chrome at localhost:8989
I’ve played around with different options like --remote-allow-origins=* and --remote-debugging-address=0.0.0.0, but no luck so far. Any ideas on how to make this work? Has anyone successfully connected to a running headless Chrome browser with Selenium before? I’d really appreciate any tips or suggestions!
hey runningriver, i’ve run into this before. for headless chrome, try adding ‘–no-sandbox’ to ur options. also double-check the port number - sometimes it changes. if that doesn’t work, maybe try a different webdriver like firefox? good luck!
I’ve dealt with similar issues connecting to headless Chrome. One trick that worked for me was explicitly setting the debugging port in both the browser launch command and the Selenium capabilities. Something like:
chrome_options.add_argument('--remote-debugging-port=9222')
capabilities = webdriver.DesiredCapabilities.CHROME.copy()
capabilities['goog:chromeOptions'] = {'debuggerAddress': 'localhost:9222'}
driver = webdriver.Remote('http://localhost:4444', capabilities)
Also, make sure your Chrome and ChromeDriver versions match exactly. Mismatched versions can cause weird connection errors. If all else fails, you might need to dig into the Selenium source code to see exactly how it’s trying to connect. It’s a pain, but sometimes that’s the only way to track down these obscure issues.
I’ve encountered this issue before when working with headless Chrome and Selenium. One solution that worked for me was to use the Chrome DevTools Protocol (CDP) instead of the standard WebDriver protocol. Here’s a quick example of how you can set it up:
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
options = Options()
options.add_argument('--headless')
options.add_argument('--remote-debugging-port=9222')
driver = webdriver.Chrome(options=options)
Then, to connect to the running browser:
from selenium import webdriver
capabilities = {
'browserName': 'chrome',
'goog:chromeOptions': {
'debuggerAddress': 'localhost:9222'
}
}
driver = webdriver.Remote(command_executor='http://localhost:9515', desired_capabilities=capabilities)
This approach has been more reliable for me when dealing with headless Chrome instances. Just make sure your ChromeDriver version matches your Chrome version exactly.