I am writing selenium test scripts using the industry standard of webdriver waits before interacting with elements, but I still frequently find my tests are failing, and it seems to be due to a race condition.
Here's the example I have been running into lately:
Go to the product catalog page
Apply a filter
Wait for the filter to be applied
Click the save button on the product which loads after the filter is applied
Step number 4 only works if I place a Thread.Sleep() in front of the step - using webdriverwait is not enough. I'm guessing this is because the webdriverwait only waits until the element is attached to the DOM, even though the relevant JavaScript click event has not been added to the element.
How do you get around this issue? Is there an industry standard for dealing with this race condition?
EDIT This was resolved by upgrading to the latest version firefox. Thanks everyone!
As we discovered in comments, updating Firefox to the latest version did the trick.
The code looks really good to me and makes total sense.
What I would try is to move to the element before making a click:
Actions builder = new Actions(WebDriver);
IWebElement saveButton = wait.Until(ExpectedConditions.ElementIsVisible(By.CssSelector(".button-wishlist")));
Actions hoverClick = builder.MoveToElement(saveButton).Click();
hoverClick.Build().Perform();
As we've discovered in comments, the issue is related to the size of the window (the test passed without a Thread.sleep() if the browser window is maximized). This makes me think that if you scroll to the element before making a click it could be enough to make it work:
IWebElement saveButton = wait.Until(ExpectedConditions.ElementIsVisible(By.CssSelector(".button-wishlist")));
((IJavaScriptExecutor)driver).ExecuteScript("arguments[0].scrollIntoView(true);", saveButton);
Actions hoverClick = builder.MoveToElement(saveButton).Click();
hoverClick.Build().Perform();
Take a look at this SO post for custom wait method. Sounds like element presence is not enough of a check in your case because the button may be present at all times in the DOM. What you need is something along the lines of ExpectedConditions.elementToBeClickable().
I am not familiar with the C# API but it looks like there is no built in method to do the same thing as in Java. So you could write a custom wait function that will have checks according to your needs.
Related
Test cases fail while not finding a link or any validation messages after a button click.
I used explicit waits for page to load:
var waitForDocumentReady = new WebDriverWait(WebDriver, TimeSpan.FromSeconds(10));
waitForDocumentReady.Until((wdriver) => (WebDriver as IJavaScriptExecutor).ExecuteScript("return document.readyState").Equals("complete"));
For wait specific div of validation messages:
WebDriverWait wait = new WebDriverWait(WebDriver, TimeSpan.FromSeconds(10));
wait.Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementExists(By.ClassName("validationErrors")));
But test cases pass sometimes with pipeline and fails sometimes.
I would recommend following:
When ever your tests fail take a snapshot at that moment.
sometimes when you run your tests locally the network communication
is a bit faster than running on server. Which means a spinner or a
loading control may not appear locally because results were retrieved
fast enough but the loader will appear when there is delay from
server in sending the response to client.
If you are trying to run your tests in FF headless on remote grid
setup then it is not yet stable in my experience.
Identify the pattern in failed scenarios which frequently fail and
try and run them multiple times in a loop and identify the pattern of
failure. In one of my case there was an actual bug in the performance
of the application which used to get reproduced whenever the tests
ran immediately in bulk
I was having this issue, except my test would always fail in Azure Pipelines but pass locally. Not running in "headless" mode fixed my problem. To do this, make sure "Test mix contains UI tests" is checked in your "Visual Studio Test" task.
There are a couple of things you need to take care as follows:
Test cases fail while not finding a link or any validation messages after a button click: A lot depends on the attributes of the button. In case the button contains either of the following attributes/events the DOM Tree would be getting updated and subsequently trying to find the desired element may fail:
onclick() event:
<button onclick="myFunction()">Click me</button>
jQuery click() Event:
$("p").click(function(){
alert("The paragraph was clicked.");
});
So after a button click, to find the desired element you need to induce you have to induce WebDriverWait for the ElementExists().
You can find a relevant discussion in ExpectedConditions.ElementIsVisible returns TimeoutException even when element is present
ExecuteScript("return document.readyState").Equals("complete"): This line of code is not that effective to ensure if the desired element(s) are present/visible/interactable with in the HTML DOM.
You can find a relevant discussion in Do we have any generic function to check if page has completely loaded in Selenium
However to wait for specific div with ElementExists() should have worked. The relevant HTML would have helped us to analyze what went wrong. However, if the validationErrors related element is based on HTML5 Constraint validation then you have to use the GetAttribute() method.
You can find a relevant discussion in How to handle html5 constraint validation pop-up using Selenium?
I am unable to interact with an element using browser tests. It says the element is not interact-able, or not visible. This doesn't happen in Acceptance
Sometimes this solution doesn't work because the element is unavailable for some other cryptic reason.
We just had a situation where we couldn't use a <select> element to pick one of the options.
Further more, there was behaviour that was being triggered by the "change" event when the option was selected.
We were able to solve it like this.
$js = "jQuery('#chosen-option-quantity-2').val('2').trigger('change');";
$I->executeJS($js);
so the first command selects the option, and the second triggers the change event.
I hope that helps some one, even if it is me in the future.
The problem that is happening here is that the html element is being hidden by something, probably css somewhere. Because it is hidden (display:none), WebDriver can't see it, and therefore can't interact with it.
In order to fix this problem, you need to use JS to un-hide the element.
use this $I->executeJS('jQuery("#your-css-selector").show()');
This doesn't happen in Acceptance tests because PHP Browser looks at the Page Source, and so can see everything, while WebDriver see's what a user see's on the browser.
You may use PhpBrowser
It works only with HTML then how PhantomJs emulate the real browser
But, with PhpBrowser you can't see what see your browser (only HTML such I said)
Another way, try executeJs with PhantomJs as it said before
I have some selenium based tests a feature where an item is deselected on the page, which causes that element to be removed from the page. Because it is ajax based I do a click for the deselect action, and then wait for the element to no longer be on the page before moving on. the basic flow is
click(TargetElement)
if(isElementPresent(targetElement)){
waitForNotVisible(targetElement)
}
...
This seems to work 100% of the time when run against a local selenium server instance, but when run against the selenium grid I have set up, it always times out on waitforNotVisible (in both cases, the conditional is always met).
Originally when this was failing, I didn't have the conditional and I thought that would clear it up, but it didn't. Maybe my expectations for waitForNotVisible are not correct, but I wonder why this would be working locally and not against the grid. All of my other tests seem to work fine via both methods.
And yes, I am using selenium 1; at the moment moving to selenium2/Webdriver is not an option in the short term, so please don't suggest using webdriver as a solution. At the moment I'm most interested in understanding why this would fail as-is.
After implementing filepicker.io, some of our Selenium regression tests have started failing. The failures (intermittent, but more often than not in some circumstances) are that clicks are ignored on WebElements found via XPath queries. e.g.
driver.findElement(By.xpath("//a[text()='Demo data']")).click();
Adding a Sleep(2000) between findElement() and click() generally resolves the problem. (I say generally because Sleep(1000) was mostly enough, until it wasn't, so I made it Sleep(2000)...)
Checking element.isDisplayed() has not helped. The problem disappears if we stop including the filepicker.io JavaScript file.
Is it something to do with filepicker.io introducing an IFRAME? We have also noticed that JQuery's document.ready() seems to be now invoked twice.
As usual with this kind of problems, you are trying to find an element that is not yet available on the page due to AJAX request still downloading/processing it. You need to wait for the element to appear on the page.
There are three ways to do this:
Using sleep(). This is the discouraged way. You should not use hardcoded sleeps, because you'll either wait too long (making the tests unnecessarily slow) or too short (failing the test).
Use Implicit wait. That will always wait for an element if it's not found.
driver.manage().timeouts().implicitlyWait(5, TimeUnit.SECONDS);
Use explicit wait. That enables you to wait explicitly for one element to (dis)appear / become available / whatever.
WebDriverWait wait = new WebDriverWait(driver, 10);
WebElement element = wait.until(ExpectedConditions.elementToBeClickable(By.linkText("Demo data")));
We now run this code first after opening any page that includes filepicker.js:
while (FindElementsMaybeNone(By.cssSelector("#filepicker_comm_iframe")).size() == 0)
Sleep(50);
while (driver.switchTo().frame("filepicker_comm_iframe") == null)
Sleep(50);
driver.switchTo().defaultContent();
We guess that filepicker's dynamic IFRAME insertion is discombobulating Firefox or Selenium. I'm not marking this as the answer because I don't really know why it works.
The webpage that I'm testing is using knockout. On other pages on our site that are not currently using knockout I'm not having the same problem. The scenario I have is where the page opens, I enter in various required fields and click the save button. At some point between when it enters a value in the last text field and when it clicks the save button the fields that previously had values become cleared out, and thus the script can't continue. Here is an example of the code that I'm running:
driver.findElement(By.id("sku")).clear();
driver.findElement(By.id("sku")).sendKeys(itemNo);
driver.findElement(By.id("desktopThankYouPage")).clear();
driver.findElement(By.id("desktopThankYouPage")).sendKeys(downloadUrl);
driver.findElement(By.id("mobileThankYouPage")).clear();
driver.findElement(By.id("mobileThankYouPage")).sendKeys(mobileDownloadUrl);
driver.findElement(By.id("initialPrice")).clear();
driver.findElement(By.id("initialPrice")).sendKeys(initialPrice);
driver.findElement(By.id("submitSiteChanges")).click();
Like I said, between the time it enters text in the last field and the time it clicks save the fields that previously had text in them get cleared out, and thus my test fails. The problem is it doesn't always happen. Sometimes the test runs fine, other times it doesn't.
I've tried putting Thread.sleep(x); all over the place to see if pausing at certain points would fix the problem. I also have tried using javascript to wait in the background for any ajax that might be running. Also have the implicit wait of driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS). None of it seemingly has made any difference.
I'm running version 2.13 of selenium server and all my tests run on Firefox 8.
Any help on this would be greatly appreciated!
Firefox has a bug which prevents some events from being executed while the browser window is out of focus. This could be an issue when you're running your automation tests - which might be typing even if the window is out of focus.
The point is that knockout model updates are triggered (by default) with the change event. If it's not being executed, it's underlying model won't be up-to-date.
To fix this issue I triggered the change event "manually", injecting javascript into my tests.:
//suppose "element" is an input field
element.sendKeys("value");
JavascriptExecutor jsExecutor = (JavascriptExecutor) driver;
jsExecutor.executeScript("$(arguments[0]).change();", element);
As you might have noticed, I'm using jQuery to trigger the change event. If you're not using jQuery on your app, you can check here how to trigger it using vanilla javascript.
Hope that helps somebody.
I had the exact same problem. I would guess also that your code works fine in Chrome but not firefox, and that it always works when you do it manually?
Anyway, the problem is likely to be that Selenium doesn't really behave the same way as a real user, and doesnt trigger the same events. When you "submit" the form, it sometimes won't have executed the "change" event on a text area, meaning that it won't have changed.
I had the same problem testing Backbone.modelbinding, which uses the "change" event to update the model from the form. Knockout also uses the "change" event, but fortunately it can also use the "keyup" event. See valueUpdate in the docs:
<input data-bind="value: someValue, valueUpdate: 'keyup'" />
Anyway, that reproducibly solved it for me, and didnt need any sleeps once I had that done. The downside is that you'd be running the event more than is necessary in production, in order to make tests work. Another downside is that you if you want to run some code when a value changes, you'll now get one event per keypress instead of one per field change, which sucks sometimes.
There is another solution, which is to make Selenium fire the change event yourself, for example: Selenium IE change event not fired. It's also suboptimal, but what can you do.
You could also try putting the focus on a button before you click it. Don't know if that will work, I haven't tried it.
I was facing the same issue, while using JavaScriptExecutor for sending keys to text fields.
Using below code in IE (same code is working with chrome):
(JavascriptExecutor) driver.executeScript("arguments[0].value = '" + value + "';", element);
After updating the code to simple "sendKeys()" method, it resolved my issue:
element.sendKeys("some text");