CODEWITHSUNDEEP
seleniumgoogle-chromeselenium-webdriverjasmineselenium-chromedriver
ian turner
ian turner

Reputation: 61

WebDriverError: no such session error using ChromeDriver Chrome through Selenium and Jasmine

I'm trying to make an automated test for my webpage and I'm using Jasmine in tandem with selenium.

When testing on chrome (using chromedriver) I get, unpredictably, the error below. It happens frequently enough that when I run a test suite it hardly ever finishes.

Ive found evidence of this bug but cant find a solid answer: https://bugs.chromium.org/p/chromedriver/issues/detail?id=732 (granted this was for chromium and I'm using chrome) 

WebDriverError: no such session
  (Driver info: chromedriver=2.21.371459 (36d3d07f660ff2bc1bf28a75d1cdabed0983e7c4),platform=Mac OS X 10.11.5 x86_64)
    at WebDriverError (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/error.js:27:10)
    at Object.checkLegacyResponse (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/error.js:639:15)
    at parseHttpResponse (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/http/index.js:538:13)
    at /Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/http/index.js:472:11
    at ManagedPromise.invokeCallback_ (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:1379:14)
    at TaskQueue.execute_ (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:2913:14)
    at TaskQueue.executeNext_ (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:2896:21)
    at /Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:2820:25
    at /Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:639:7
    at process._tickCallback (node.js:369:9)
From: Task: WebElement.isDisplayed()
    at Driver.schedule (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/webdriver.js:377:17)
    at WebElement.schedule_ (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/webdriver.js:1744:25)
    at WebElement.isDisplayed (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/webdriver.js:2110:17)
    at driver.findElements.then.error (/Users/XXXXXXX/Documents/sweetmeeting/Test/front_end_testing/spec/dashboard_tester.js:251:34)
    at ManagedPromise.invokeCallback_ (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:1379:14)
    at TaskQueue.execute_ (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:2913:14)
    at TaskQueue.executeNext_ (/Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:2896:21)
    at /Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:2775:27
    at /Users/XXXXXXX/Documents/sweetmeeting/node_modules/selenium-webdriver/lib/promise.js:639:7
    at process._tickCallback (node.js:369:9)

Upvotes: 5

Views: 9099

Answers (4)

undetected Selenium
undetected Selenium

Reputation: 193068

This error message...

WebDriverError: no such session
  (Driver info: chromedriver=a.b.c (36d3d07f660ff2bc1bf28a75d1cdabed0983e7c4),platform=Mac OS X 10.11.5 x86_64)

...implies that the ChromeDriver was unable to communicate with the existing Browsing Context i.e. Chrome Browser session.

We have discussed and analyzed this issue within the discussion Issue 732: No such session error - inconsistent problem which appears when running tests for a prolonged period. This error is usually observed after an extended period of executing the Test Suite as follows:

[0127/105308:ERROR:nacl_helper_linux.cc(289)] NaCl helper process running without a sandbox!
Most likely you need to configure your SUID sandbox correctly
[489.849][INFO]: RESPONSE FindElements unknown error: session deleted because of page crash
from tab crashed
  (Session info: chrome=p.q.r.s)
[489.849][DEBUG]: Log type 'driver' lost 0 entries on destruction
[489.849][DEBUG]: Log type 'browser' lost 9 entries on destruction

This error is defined in nacl_helper_linux.cc as follows:

// If the Zygote has started handling requests, we should be sandboxed via
// the setuid sandbox.
if (!IsSandboxed()) {
  LOG(ERROR) << "NaCl helper process running without a sandbox!\n"
    << "Most likely you need to configure your SUID sandbox "
    << "correctly";

Precisely the FindElement(s) method have FAILED due to sandbox issue and Page Crash occured due to session deletion

Solution

This error can happen due to a lot of diverse reasons and the solution to address this error are as follows:

  • Initiate the Chrome session configuring ChromeDriver with the argument --disable-impl-side-painting
    • Additionally, you can also add the argument --enable-gpu-rasterization which allow heuristics to determine when a layer tile should be drawn with the Skia GPU backend. Only valid with GPU accelerated compositing + impl-side painting.
    • As an option, you can also add the argument --force-gpu-rasterization which always uses the Skia GPU backend for drawing layer tiles. Only valid with GPU accelerated compositing + impl-side painting. Overrides the kEnableGpuRasterization flag.

  • This error is also observed when the server does not recognize the unique session identifier. This happens if the session has been deleted or if the session ID is invalid in either of the following ways:

    • Explicit session deletion: A WebDriver session is explicitly deleted when explicitly invoking the quit() method as follows:

      from selenium import webdriver
from selenium.common.exceptions import InvalidSessionIdException

driver = webdriver.Chrome(executable_path=r'C:\Utility\BrowserDrivers\chromedriver.exe')
print("Current session is {}".format(driver.session_id))
driver.quit()
try:
    driver.get("https://www.google.com/")
except Exception as e:
    print(e.message)

#Console Output:
Current session is a9272550-c4e5-450f-883d-553d337eed48
No active session with ID a9272550-c4e5-450f-883d-553d337eed48

    • Implicit session deletion: A WebDriver session is implicitly deleted when you close the last window or tab invoking close() method as follows:

      driver = webdriver.Chrome(executable_path=r'C:\Utility\BrowserDrivers\chromedriver.exe')
print("Current session is {}".format(driver.session_id))
# closes current window/tab
driver.close()
try:
    driver.get("https://www.google.com/")
except Exception as e:
    print(e.message)

#Console Output:
Current session is a9272550-c4e5-450f-883d-553d337eed48
No active session with ID a9272550-c4e5-450f-883d-553d337eed48

  • You may also have to add the argument --no-sandbox

  • Chrome seem to crash often in Docker containers on certain pages due to too small /dev/shm. Similarly, you may have to fix the small /dev/shm size.

  • An example:

    sudo mount -t tmpfs -o rw,nosuid,nodev,noexec,relatime,size=512M tmpfs /dev/shm

  • It also works if you use -v /dev/shm:/dev/shm option to share host /dev/shm

  • Another way to make it work would be to add the chrome_options as --disable-dev-shm-usage. This will force Chrome to use the /tmp directory instead. This may slow down the execution though since disk will be used instead of memory.

    chrome_options.add_argument('--disable-dev-shm-usage')

Reference

You can find a couple of detailed discussions in:

Upvotes: 1

Sergey Pleshakov
Sergey Pleshakov

Reputation: 8948

Sometimes we just expect any problem to be very complex and are looking for its cause far too deep, when a problem could be so obvious.

I was seeing this issue when I explicitly called browser.close() as an exception handler in my logout() method. It terminated the session and all of the following protractor tests were throwing this error.

Once I removed browser.close() and just threw an error instead, the problem was solved.

Upvotes: 0

Arnon Axelrod
Arnon Axelrod

Reputation: 1672

I recently encountered this exception too. It first appeared to be undeterministic too, but after thorough investigation I realized that it happens deterministrically if you call ChromeDriver.Close() and then tries to FindElement.

In my case, ChromeDriver.Close() was called in an exception handler of a previous test, which happened due to a timing issue. This only affected the next test so it added to the feeling that this issue is flaky. But as I said, my investigation revealed that it is deterministic.

Having said that, this is my experience with that error. Could be that your case is different...

Upvotes: 6

rickyf
rickyf

Reputation: 91

We've also been struggling with this issue for a long time now and recently resolved it so thought I would post here incase it helps someone else.

Turns out for us it was memory related. We run our tests inside a docker container and the docker default dev/shm size is 64mb. Increasing this resolved the "no such session" issue for us.

We use docker compose so just added shm_size: 256M to the docker-compose.yml file.

Upvotes: 9

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