How to reuse existing Selenium browser session

Suppose you are running a long Selenium test. The test runs fine but fails towards the end as some element was not found or was not clickable. Ideally, you would like to fix the locator and check it immediately. Now you wonder if you can reuse your browser session from the same point where the failure occurred. This post shows you how to do just that! This would help you to debug the locators used quickly, instead of running your whole test again.


Extract session_id and _url from driver object

We are taking advantage of the fact that Selenium lets you attach a driver to a session id and an URL. You can extract your session id and _url from the driver object as mentioned below

session_url = driver.command_executor._url  
session_id = driver.session_id

Tie it up with your framework

In case you are using a framework, you can print out the session id and url in the method where you try to get the element. In an example shown below, I am using a get_element method which would return the DOM element. I am printing the session id and url whenever the find_element method fails

def get_element(self,xpath):
        "Return the DOM element of the xpath or 'None' if the element is not found "
        dom_element = None
        try:
            dom_element = self.driver.find_element(xpath)
        except Exception,e:
            self.write(str(e),'debug')
            self.write("Check your locator-'%s"%xpath)
            #Print the session_id and _url in case the element is not found
            self.write("In case you want to reuse session, the session_id and _url for current browser session are: %s,%s"%(driver.session_id ,driver.command_executor._url))
 
        return dom_element

Use the session id and url

Now you can use the session id and url, in order to debug the locators. Open python command line tool and use the below code

 
from selenium import webdriver
 
#Pass the session_url you extracted
driver = webdriver.Remote(command_executor=session_url,desired_capabilities={})
 
#Attach to the session id you extracted
driver.session_id = session_id
 
#Resume from that browser state
elm = driver.find_element_by_xpath("xpath")
 
elm.click() #Perform required action

Note1: Currently I am able to reuse the session extracted only from Chrome browser. For Firefox there are some Issue. Link 1 and Link 2

Note2: This code is present in our open-sourced Python-Selenium test automation framework based on the page object pattern. We strongly recommend you check it out!

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21 thoughts on “How to reuse existing Selenium browser session

  1. Thank you for this!
    In my case the webdriver.remote opens a new completely empty window above the existent one.

    It’s circumvented by sendKeys Alt+F4 and/or AppActivate(“Google Chrome”)
    Those functions can be found in win32com.client

    1. I too observed the empty window opening up. Thanks for letting me know how to find a way around it.

    2. Actually, to fix this annoying empty window issue, you should just close browser before you re-set session_id for it:

      cls.browser = webdriver.Remote(command_executor=session_url, desired_capabilities={})
      cls.browser.close()
      cls.browser.session_id = session_id

  2. Hi, the code no longer works.
    I am using selenium 3.9.0 with python, your code ever open new browser.
    I tested with chromedriver and geckodriver(firefox).
    Please, inform version of your selenium

    1. Hi Jhony,
      Can you let me know what error you get when you try out the code?. Yes, the code opens a new browser session and you can try the suggestions in some of the above comments to fix that issue. My selenium version is 3.6.0

    2. Because of the version compactability between your selenium and firefox driver it will not work. Try o downgrade your firefox driver

  3. the best way to void create a emtpy windows is mock start_session(), the code below:

    def start_session(self, *args):
    ”’ mock method, to void create a emtpy chrome page ”’
    pass

    def reuse_driver(url, session_id):
    webdriver.Remote.start_session = start_session # user mocked method, do nothing
    driver = webdriver.Remote(command_executor=url)
    driver.session_id = session_id
    driver.w3c = None
    return driver

  4. Has anyone tried this when running Selenium on Browserstack?…

    When launching the new driver, it seems it’s not possible to change the session id. (driver.session_id = session_id ) So the browserstack session gets stuck.

    Any tips or advice would be really helpful…

  5. If the browser session was opened by some other application and we want to perform automation on that browser session, then is it possible?

    1. Hi John,
      We need session_id and Session_url to do this. I don’t know of a way to get this for an already opened session by some other application

  6. Was looking for this particular implementation of reusing the browser, but not found in your framework, where is it ?

    1. Hi,

      The posts only gives an example on how you can use session id and url in the framework. In this example we are printing the session id and url whenever the find_element method fails. You can print out the session details in the method where you try to get the element.

      I hope this information helps !!!

  7. Hi nice information,

    Am I right about this:( in my understanding) your code is that you run fistly run it via python so because of that, you can get the ID of
    session_url = driver.command_executor._url
    session_id = driver.session_id
    but how to use already opened selenium(manual opening or already open by other python script that already stop). Let say we have opened 3 window selenium. How to get the list the session ID of that three ‘session_url’ and ‘session_id’ and so we can control the right one which opened the url https://google.com.

    1. Hi,
      You could use get.windowshandles() to store all the session ids of the open windows. You could also print store the session_id as soon as the window is spawned.
      I would suggest using a similar code:

      windows= get.windowhandles()
      for window in windows:
             driver.switch_to_window(window)
             url=driver.getCurrentUrl()
             print(url)
             if url='google.com':
                        print("window")
      
      1. I am using SeleniumBasic with VBA for Microsoft Access and have asked this question and can’t get an answer anywhere:

        Can someone please help me reconnect in vba to an existing selenium webdrover session. I figured out how to get the sessionID, the driver IP and the driverInfo but can’t quite figure out the VBA syntax.

        Thanks,

        Andrew

  8. Hi,
    I have a problem. I search to reuse driver (webdriver) for keep the same instance of my browser and not reopen an other browser. In my script, the driver is undefined in my function test.
    Help me please if someone have a solution.
    My code with nodeJS (in javascript):

    var express = require(‘express’);
    var app = express();
    var ip = “localhost”
    var port = 80;
    var server = require(“http”).createServer(app);
    var io = require(‘socket.io’)(server);
    var webdriver = require(“selenium-webdriver”);

    app.use(bodyParser.json());
    app.use(bodyParser.urlencoded({ extended: true }));
    app.use(‘/’, express.static(__dirname + ‘/’ + application));

    server.listen(port, function() {
    var driver = new webdriver.Builder().forBrowser(‘firefox’).build();
    driver.get(“http://www.google.com”); //it’s ok
    });

    io.sockets.on(‘connection’, function(socket) {
    //call of test function with socket io
    socket.on(“test”, function(data) {
    driver.get(“http://www.test.com”); //it’s ko => driver is undefined
    });
    });

    1. Hi Jeremy,

      By reading the script I understood that you have been using Firefox browser. As we have mentioned in our blog to reuse existing selenium browser session works only for Chrome browser. Please refer to the attached link in the blog.

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