Selenium Camp 2018

1. Selenium Waits
deep dive

2. Yaroslav
Pernerovsky
Automation Team Lead,
GlobalLogic
/in/yaroslav-pernerovsky-0559b51
/yaroslav.pernerovsky

3. @Test
public void simpleAction() {
driver.get("http://www.google.com");
driver.findElement(By.name("q"))
.sendKeys("Search String" + Keys.ENTER);
driver.findElement(By.cssSelector("h3.r"))
.click();
}

4. @Test
public void simpleAction() {
driver.get("http://www.google.com");
driver.findElement(By.name("q"))
.sendKeys("Search String" + Keys.ENTER);
driver.findElement(By.cssSelector("h3.r"))
.click();
}

6. Sleep
Thread.sleep(1000);

7. Sleep

8. Sleep

10. Sleep
//Insanely Long program operation
timeInSeconds = 60*50;
...
sleep(timeInSeconds*1000);

11. Sleep

12. Sleep

13. Sleep

14. Sleep

15. Sleep

17. while(true) {
if (System.currentTimeMillis()-startTime > timeout){
throw new TimeoutException();
}
try {
return driver.findElement(locator);
}
catch (NoSuchElementException e) {}
Thread.sleep(500);
}

18. while(true) {
if (System.currentTimeMillis()-startTime > timeout){
throw new TimeoutException();
}
try {
return driver.findElement(locator);
}
catch (NoSuchElementException e) {}
Thread.sleep(500);
}
Timeout Exception
Polling interval
Exception ignoring
Wait condition
Timeout exit condition

19. Implicit wait
Explicit wait

20. chromedriver
geckodriver
IEDriverServer
Implicit waits hereExplicit waits here

21. Implicit Wait
driver.manage().timeouts().
implicitlyWait(10, TimeUnit.SECONDS);
driver.manage().timeouts().
pageLoadTimeout(10, TimeUnit.SECONDS);
driver.manage().timeouts().
setScriptTimeout(10, TimeUnit.SECONDS);

22. findElement()
• Wait until element appeared in DOM
• Return first element if more than one present
• Throws NoSuchElementException
Implicit Wait

23. findElements()
• Wait until at least one element appeared in DOM
• Return collection of all found elements
• Return empty collection if no elements found
Implicit Wait

24. Implicit Wait

25. Implicit waits are a terrible mistake I've
made and I apologies for them
Simon Stewart, d
Creator of WebDriver

26. public boolean isElementPresent(By locator) {
return driver.findElements(locator).size() > 0;
}
if (isElementPresent(login))
driver.findElement(login).click();
if (!isElementPresent(login))
driver.findElement(logout).click();
Implicit Wait

27. public boolean isElementNotPresent(By locator) {
try{
driver.manage().timeouts()
.implicitlyWait(0, TimeUnit.SECONDS);
return driver.findElements(locator).size() == 0;
}
finally{
driver.manage().timeouts()
.implicitlyWait(default, TimeUnit.SECONDS);
}
}
Implicit Wait

28. Implicit Wait

29. Implicit Wait

30. Implicit Wait

33. WebDriverWait wait = new
WebDriverWait(driver, 10);
wait.until(driver ->
driver.findElement(locator));
wait.until(ExpectedConditions
.elementToBeClickable(locator));
Explicit Wait

34. Explicit Wait
WebDriverWait wait = new
WebDriverWait(driver, 10,100);
wait.withMessage("Error Message");
wait.ignoring(Exception.class);

36. wait.until(driver ->
driver.findElement(locator));
Explicit Wait

37. Explicit Wait

38. wait.until(driver ->
driver.findElements(locator).size() > 0);
Explicit Wait

39. Explicit Wait

40. Client Side (500ms)
Can wait for anything
Explicit usage
TimeoutException
Multiple network calls
Explicit Implicit
Driver Side (100ms)
Element appeared in DOM
Works automatically
NoSuchElementException
Single network call

45. wait = new WebDriverWait(driver,5);
driver.manage().timeouts()
.implicitlyWait(10, TimeUnit.SECONDS);
wait.until(ExpectedConditions
.presenceOfElementLocated(locator));
How long will Test wait ?
5 15
C: 10 25

46. public static ExpectedCondition<WebElement> presenceOfElementLocated(final By locator) {
return new ExpectedCondition<WebElement>() {
@Override
public WebElement apply(WebDriver driver) {
return findElement(locator, driver);
}
...
private static WebElement findElement(By by, WebDriver driver) {
try {
return driver.findElements(by).stream().findFirst().orElseThrow(
() -> new NoSuchElementException("Cannot locate an element using " + by));
} catch (NoSuchElementException e) {
throw e;
} catch (WebDriverException e) {
log.log(Level.WARNING,
String.format("WebDriverException thrown by findElement(%s)", by), e);
throw e;
}
}

47. wait = new WebDriverWait(driver,5);
driver.manage().timeouts()
.implicitlyWait(10, TimeUnit.SECONDS);
wait.until(ExpectedConditions
.presenceOfElementLocated(locator));
Which exception will be thrown ?
A: Timeout NoSuchElement
Both None

48. wait = new WebDriverWait(driver,10);
driver.manage().timeouts()
.implicitlyWait(5, TimeUnit.SECONDS);
wait.until(ExpectedConditions
.presenceOfElementLocated(locator));
How long will Test wait ?
5 15
C: 10 25

49. wait = new WebDriverWait(driver,11);
driver.manage().timeouts()
.implicitlyWait(5, TimeUnit.SECONDS);
wait.until(ExpectedConditions
.presenceOfElementLocated(locator));
How long will Test wait ?
5 B: 15
11 26

50. wait = new WebDriverWait(driver,5);
driver.manage().timeouts()
.implicitlyWait(10, TimeUnit.SECONDS);
wait.until(ExpectedConditions.not(
ExpectedConditions.presenceOfElementLocated(locator));
How long will Test wait if element is present?
A: 5 15
10 25

51. wait = new WebDriverWait(driver,5);
driver.manage().timeouts()
.implicitlyWait(10, TimeUnit.SECONDS);
wait.until(ExpectedConditions.not(
ExpectedConditions.presenceOfElementLocated(locator));
How long will Test wait if element is not present?
C:
5 15
10 25

53. Don't use Implicit wait!
Always set implicit timeout lower than explicit
Timeouts must be multiple to each other
Take special care to 'not present' conditions
Use Selenide

54. 46 %
29 %
20 %
5 %