Can Selenium interact with an existing browser session?

Question

Does anybody know if Selenium (WebDriver preferably) is able to communicate with and act through a browser that is already running before launching a Selenium Client?

Answer 1

This is a pretty old feature request: Allow webdriver to attach to a running browser . So it's officially not supported.

However, there is some working code which claims to support this: https://web.archive.org/web/20171214043703/http://tarunlalwani.com/post/reusing-existing-browser-session-selenium-java/.

Answer 2

I got a solution in python, I modified the webdriver class bassed on PersistenBrowser class that I found.

https://github.com/axelPalmerin/personal/commit/fabddb38a39f378aa113b0cb8d33391d5f91dca5

replace the webdriver module /usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/webdriver.py

Ej. to use:

from selenium.webdriver.common.desired_capabilities import DesiredCapabilities

runDriver = sys.argv[1]
sessionId = sys.argv[2]

def setBrowser():
    if eval(runDriver):
        webdriver = w.Remote(command_executor='http://localhost:4444/wd/hub',
                     desired_capabilities=DesiredCapabilities.CHROME,
                     )
    else:
        webdriver = w.Remote(command_executor='http://localhost:4444/wd/hub',
                             desired_capabilities=DesiredCapabilities.CHROME,
                             session_id=sessionId)

    url = webdriver.command_executor._url
    session_id = webdriver.session_id
    print url
    print session_id
    return webdriver

Answer 3

This snippet successfully allows to reuse existing browser instance yet avoiding raising the duplicate browser. Found at Tarun Lalwani's blog.

from selenium import webdriver
from selenium.webdriver.remote.webdriver import WebDriver

# executor_url = driver.command_executor._url
# session_id = driver.session_id

def attach_to_session(executor_url, session_id):
    original_execute = WebDriver.execute
    def new_command_execute(self, command, params=None):
        if command == "newSession":
            # Mock the response
            return {'success': 0, 'value': None, 'sessionId': session_id}
        else:
            return original_execute(self, command, params)
    # Patch the function before creating the driver object
    WebDriver.execute = new_command_execute
    driver = webdriver.Remote(command_executor=executor_url, desired_capabilities={})
    driver.session_id = session_id
    # Replace the patched function with original function
    WebDriver.execute = original_execute
    return driver

bro = attach_to_session('http://127.0.0.1:64092', '8de24f3bfbec01ba0d82a7946df1d1c3')
bro.get('http://ya.ru/')

Answer 4

All the solutions so far were lacking of certain functionality. Here is my solution:

public class AttachedWebDriver extends RemoteWebDriver {

    public AttachedWebDriver(URL url, String sessionId) {
        super();
        setSessionId(sessionId);
        setCommandExecutor(new HttpCommandExecutor(url) {
            @Override
            public Response execute(Command command) throws IOException {
                if (command.getName() != "newSession") {
                    return super.execute(command);
                }
                return super.execute(new Command(getSessionId(), "getCapabilities"));
            }
        });
        startSession(new DesiredCapabilities());
    }
}

Answer 5

Javascript solution:

I have successfully attached to existing browser session using this function

webdriver.WebDriver.attachToSession(executor, session_id);

Documentation can be found here.