Selenium Webdriver connection pooling - selenium

Question

I have my application automated, which has some 70+ scripts and runs against Selenium Grid which is open to other applications too.
My question is, is there any connection pooling api for WebDriver? so that i can re use webdriver objects efficiently across my scripts. I don't want my scripts wait for IE slots and fail because of time out errors if they cannot get one.
Also, i beleive it would enhance the performance of scripts execution.
Thanks.

Answer 1

Our tests are very small and so fast that the webdrivers took longer to instantiate than the tests. So we pooled the webdrivers, like #premganz suggested, but using Apache Commons Pool. We considered writing our own webdriver list-managed pool but found using the well-established Apache Pool was simple to implement, robust and scalable. Our tests run over 80 WebDrivers concurrently.
Example WebdriverFactory:
public class WebdriverFactory extends BasePooledObjectFactory<RemoteWebDriver> {
private FirefoxOptions firefoxOptions = new FirefoxOptions();
public WebdriverFactory(boolean headless, int implicit_timeout_seconds) {
super();
firefoxOptions.setHeadless(headless)
.setPageLoadStrategy(PageLoadStrategy.EAGER)
.setLogLevel(FirefoxDriverLogLevel.ERROR);
}
#Override
public RemoteWebDriver create() {
FirefoxDriver webDriver = new FirefoxDriver(firefoxOptions);
webDriver.manage()
.timeouts()
.implicitlyWait(implicit_timeout_seconds, TimeUnit.SECONDS);
return webDriver;
}
/**
* Use the default PooledObject implementation.
*/
#Override
public PooledObject<RemoteWebDriver> wrap(RemoteWebDriver webDriver) {
return new DefaultPooledObject<>(webDriver);
}
/**
* When a webdriver is returned to the pool, clean it up.
*/
#Override
public void passivateObject(PooledObject<RemoteWebDriver> webDriver) {
WebDriver driver = webDriver.getObject();
try {
// close all tabs except the first
String originalHandle = driver.getWindowHandle();
for(String handle : driver.getWindowHandles()) {
if (!handle.equals(originalHandle)) {
driver.switchTo().window(handle);
driver.close();
}
}
driver.switchTo().window(originalHandle);
} catch (Exception e) {
// ...
} finally {
// ensure session data is not re-used
driver.manage().deleteAllCookies();
}
}
#Override
public boolean validateObject(PooledObject<RemoteWebDriver> webDriver) {
return true;
}
#Override
public void activateObject(PooledObject<RemoteWebDriver> webDriver) throws Exception {
}
}

Answer 2

I agree that WebDriver pooling could enhance performance of the application. On the other hand, if you are using selenium webdriver, the driver becomes stateful making it less reusable. I did a logic something like this:
Create a Driver factory that wraps a linked list of size say 10 (which implements a list and a queue).
When asked for an instance provide the middle (i==5) one from the list
Use another thread to recycle the drivers in the queue, removing ones from the head and adding new ones to the tail.
This way you can implement a constantly recycled pool and your code does not have to block on driver.create or driver.quit.