One of the difficulties I face when we do a release is regression testing – specifically testing the front-end (website) to ensure everything is working/looking correct. At the moment we have a team of 2 testers who work almost feverishly when a release is getting close to ensure that it is indeed a good release. To address this issue I have been looking at Selenium and how we can use it to automate a large portion of this regression testing.

I come from a Java background where we use Continuous Integration so I wanted to integrate Selenium testing as part of our build cycle. Selenium comes in a number of forms – IDE, Core, RC and Grid (some of which work together). In this article I will be focusing on Selenium RC – to find what the others are about head over to the Selenium website.

Since the website I work on utilizes AJAX in quite a number of places, one of the requirements I had for Selenium was that it had to be able to deal with AJAX enabled sites. Although the Selenium website doesn’t specifically talk about it, I did find help regarding the subject in their user-forums.

Below is a short write-up on the steps I took to get some basic tests running via Selenium RC. Note that you should download the Selenium RC package to get the java client libs and the Selenium server – available here.

1. Selenium Test Case

First I setup a JUnit 4 abstract class to setup selenium before my actual test class runs. You can see below in my AbstractSeleniumTest class in the setUp method I construct a DefaultSelenium object by passing in parameter values obtained from the System – this is so that I can test different environments (local dev, integration, uat etc.) configured at runtime. Also to note are the use of the new JUnit4 annotations.

public abstract class AbstractSeleniumTest {

    protected static Selenium selenium;
    protected static String SELENIUM_SERVER_HOST="selenium.server.host";
    protected static String SELENIUM_SERVER_PORT="selenium.server.port";
    protected static String SELENIUM_BROWSER_STARTCOMMAND="selenium.browser.startCommand";
    protected static String SELENIUM_BROWSER_URL="selenium.browser.url";

    @BeforeClass
    public static void setUp() {
        selenium = new DefaultSelenium(System.getProperty(SELENIUM_SERVER_HOST),
        Integer.parseInt(System.getProperty(SELENIUM_SERVER_PORT)),
        System.getProperty(SELENIUM_BROWSER_STARTCOMMAND),
        System.getProperty(SELENIUM_BROWSER_URL));
        selenium.start();
    }

    @AfterClass
    public static void tearDown() {
        selenium.stop();
    }

    public void waitForElement(final String waitingElement, String timeoutMessage) {
        new Wait() {
            public boolean until() {
                return selenium.isElementPresent(waitingElement);
            }
        }.wait(timeoutMessage);
    }
}

Now my class which will test an AJAX’ified login box.

public class AuthenticationTests extends AbstractSeleniunTest {

    @Test
    public void testUserLogin() throws InterruptedException {
        selenium.open("/");
        selenium.click("link=Login");
        waitForElement("login-form_j_username", "Login not shown");
        selenium.type("login-form_j_username", "xxxx@xxxx.com");
        selenium.type("login-form_j_password", "xxxx");
        selenium.click("login-form_0");
        waitForElement("user-home-link", "User home link not shown");
        assertTrue(selenium.isElementPresent("user-home-link"));
    }
}

2. Setting up Selenium Server

Selenium server needs to be setup on the box on which you plan to run the tests from and this box should also have some web browsers installed. I use a mac so I am testing under firefox (note – that firefox3 beta does not seem to work yet so ensure you have firefox2 ).

Once you have extracted the Selenium RC download, run the server as below.

computer:selenium-server-1.0-beta-1 alvins$ pwd
~/selenium-remote-control-1.0-beta-1/selenium-server-1.0-beta-1
computer:selenium-server-1.0-beta-1 alvins$ java -jar selenium-server.jar -interactive
alvin-singhs-computer:selenium-server-1.0-beta-1 alvins$ java -jar selenium-server.jar -interactive
23:18:15.624 INFO - Java: Apple Inc. 1.5.0_13-119
23:18:15.625 INFO - OS: Mac OS X 10.5.2 i386
23:18:15.628 INFO - v1.0-beta-1 [2201], with Core v1.0-beta-1 [1994]
23:18:15.724 INFO - Version Jetty/5.1.x
23:18:15.725 INFO - Started HttpContext[/,/]
23:18:15.726 INFO - Started HttpContext[/selenium-server,/selenium-server]
23:18:15.727 INFO - Started HttpContext[/selenium-server/driver,/selenium-server/driver]
23:18:15.732 INFO - Started SocketListener on 0.0.0.0:4444
23:18:15.732 INFO - Started org.mortbay.jetty.Server@2a5330
Entering interactive mode… type Selenium commands here (e.g: cmd=open&1=http://www.yahoo.com)

Note that if you are in a linux headless environment you must have X installed and run Xvfb before running the above.

computer:selenium-server-1.0-beta-1 alvins$ Xvfb :1
computer:selenium-server-1.0-beta-1 alvins$ export DISPLAY=:1

3. Running the Test

I use eclipse for development and so to run the test, right click on the Test class–>Run As–>Open Run Dialog–>Arguments Tab as below. The arguements are quite self explanatory – they are fed into the DefaultSelenium class as can be seen in the code from Step 1. The third argument deserves a mention – this is the browser you wish to run your tests on – some supported browsers include iexplore, konqueror, firefox, safari and opera.

Once you are all set, simply click Run and what should happen is that the test will contact the selenium server, start firefox and start executing the tests. Of course if you are running in a headless environment you will see firefox launch but running in interactive mode you should still be able to see the selenium server logging its activity.

23:24:14.037 INFO - Checking Resource aliases
23:24:14.042 INFO - Command request: getNewBrowserSession[*chrome, http://xxxx.com] on session null
23:24:14.042 INFO - creating new remote session
23:24:14.118 INFO - Allocated session 15a43743285c4dba913a3ff0ab2b5dea for http://xxxx.com, launching…
23:24:14.160 INFO - Preparing Firefox profile…
23:24:18.520 INFO - Launching Firefox…
23:24:20.819 INFO - Got result: OK,15a43743285c4dba913a3ff0ab2b5dea on session 15a43743285c4dba913a3ff0ab2b5dea
23:24:20.830 INFO - Command request: open[/, ] on session 15a43743285c4dba913a3ff0ab2b5dea
…

Depending on your build environment you will have to decide how you want to integrate these tests as part of your build. The Selenium Wiki has some great examples on different ways to do this. My company uses Bamboo (CI Server) from the great people at Atlassian and this runs the tests after successful builds.

Happy testing!