Run Selenium tests in parallel on multiple browsers

This blog is follow up from my previous one where I worked out an example to take screenshots on test failure. In this blog I am going to attempt to run the same tests however on multiple browsers and in parallel.


To achieve multi-browser parallel run of the test cases:

• I have updated the testng.xml and added config to run the tests in parallel with browser_type parameters each with its own thread, one for firefox and one for chrome.
• Updated pom.xml to start using testng.xml file to kickoff the test cases.
• Updated WebDriverManager class to be thread aware and return correct WedDriver (Firefox or Chrome) instance so that in case of test failure screenshot of correct browser can be taken.
• Minor tweak in the test case so that its aware of which browser type to run with.

The entire project is uploaded on github for reference: https://github.com/njaiswal/council-tax-band

Right, lets get to the nuts and bolts now.

testng.xml

Two test cases in the suite, TestNG will run these 2 test case with a threadpool size of 2, which means that both browsers will fire-up at almost the same time and go through the test cases in parallel which saves us time!

pom.xml (snippet)

Above pom.xml snippet tells maven to start using testng.xml to kick off the test cases. Please refer full pom.xml on github

WebDriverManager

WebDriverManager is a bit more meaty than previous blog. Instead of keeping the WebDriver instance as static variable it has a static HashMap in which it will store thread Id as the key and the WebDriver instance as value. Since our tests are now going to run on more than 1 thread we need this arrangement so that WebDriverManager knows which instance to return to onTestFailure() method based on the Thread Id.

CTaxBandTest (snippet)

As you can see above I have used the @Parameters annotation along with @BeforeClass. This basically fetches parameter browser_type from the testng.xml file and passes it as method parameter to onTimeSetUp() method. This is a key step where we call WebDriverManager.startDriver() and get correct browser instance created. As mentioned above, WebDriverManager will store the instance reference in a HashMap with thread Id as key so that any future calls to WebDriverManager.getDriverInstance() can identify which browser instance to return.

Reports

Run the tests using 'mvn test' command and you should see 2 browser instances (Firefox and Chrome) getting started at the same time and the tests being run in parallel. 

Two reports get generated (one for each browser type) with total of 4 test cases being run and more importantly both contain correct screenshots of test failures.

Again the entire project is on git hub for reference, happy testing!

Selenium: Take screenshot on test failure

Going ahead on the theme of testing publicly available websites using selenium, in this blog I want to work out an example which touches on following points:

    •    Run Selenium WebDriver tests under TestNG
    •    Use the following best practices:
    ◦    Page Object Model
    ◦    UI Mapping
    ◦    Data Driven Testing
    ◦    And most importantly take screenshot on an event of test failure
Now to do all of the above I need a publicly available website that sounds interesting enough and devise testing around it. So here we go...

Test the DirectGov Council Tax Band website, given postcode, first line of address and an expected band.
The site that we are using is  http://www.voa.gov.uk/cti/InitS.asp
 

Setup Java project with Maven 

Now import the maven project in your favorite IDE. I am using Eclipse.

Since we are going to use selenium with testng instead of junit my pom.xml looks like following.

Test and Helper Class

Now that we have got a Java project set up, lets get cracking. Since I have already done my code before writing this blog, my final directory tree looks like following.

Let me add a bit of context around what is the role of each file in the directory tree above is. Later I will add more details about each of the relevant files.

• CTaxBandTest.java - This is the testng file that contains all the test cases just by the virtue of keyword 'test' in the file name.
• CTaxBandSearch.java - Page Object Model Class. The Page Object Design Pattern provides the followingadvantages.
• There is clean separation between test code and page specific code suchas locators (or their use if you’re using a UI map) and layout
• There is single repository for the services or operations offered by thepage rather than having these services scattered through out the tests.
• WebDriverManager.java - This class will manage the singleton WebDriver instance that will be used in our tests. The importance of this manager class will become relevant when we go through the details of how to get screenshot on test failure.
• ScreenShotOnFailure.java - Contains code to capture and store screenshot on event of test failure at correct location so that these screenshots is available via test reports.
• ui_mapping.properties - UI Mapping file. Contains all the UI locators in one file for ease of modification.

 

CTaxBandTest.java

In the test case above we have used various testng annotations. The important one is @Listeners which basically defines one or more of users classes, which implement some interfaces that TestNG provides, so that when TestNG raises certain events it will look for all “classes” which are basically looking for such events and call the respective event handlers in them. In this case we are using it to define handler for onTestFailure so that we can capture the screenshot and include it in testng report.
We are also using the @DataProvider annotation to make our test case data driven which basically means that we have more than 1 data set points to run through same test case.

WebDriverManager.java

This is a static helper class which manages the only Selenium WebDriver instance we are using for all test cases. This makes access to this webdriver instance very easy later on when we want to take a screenshot on event of test failure. 

CTaxBandSearch.java

This is the Page Object Model class which knows how to navigate the website page which we want to test. As you can see I have also made use of UI Mapping best practice here and get all locators from a properties file.

ScreenShotOnFailure.java

And lastly the listener class which will override the onTestFailure handler of testng and help us get the crucial screenshot when a test case fails.

We can get hold of the webdriver instance very easily since its now managed by a WebDriverManager class. Above class also demonstrates how to include the screenshot link in the test reports.

Run the test

Now that we have all the bits and pieces in place lets run our test case. You might have not noticed but I have deliberately included a council tax band incorrect in our @DataProvider which means that 1 test case will pass and 1 fails with a screenshot!

The reports are generated in target/surefire-reports/ directory and looking at the reports... hurray screenshots at last!!!

This has been kind of a long post, but I did want to touch on a few points in one go and glad that its out there now.

Selenium WebDriver - Maven

This post I am going to share the basics of setting up and running a simple but working Selenium WebDriver example. The hypothetical requirement this example is trying to accomplish is following:

Print out all addresses on rightmove.co.uk for 3 bedroom properties for sale in Reading under £175K

Requirements looks simple. Lets get started.

Setup Java project using Maven

Assuming you have maven installed on your system, run the following command to setup a generic java project.

Update pom.xml to 

• Include selenium-firefox-driver and selenium-support dependencies.
• Generate a executable jar file. This example pom.xml assumes that your main class would be named PropertyAddressFinder.

Selenium

Import this maven project in your favourite IDE and add PropertyAddressFinder class. Java code below  should be self explanatory. It uses Selenium FirefoxDriver to open the website and search for properties .  

Run the Project

Now that we have the bits and pieces in place, we can let maven do the magic and make us a executable jar file, refer pom.xml's build section above to see how we achieve this. Executing the jar file via command line will open a firefox browser and print out whatever properties it finds.

Conclusion

Above blog demonstrates a very basic usage of selenium webdriver to automate web based tasks that cannot be otherwise achieved via well known api's.