how to run my selenium test methods in parallel using testng

Question

I am trying to run my automated tests(Selenium webdriver) in parallel using testng. this is the node which I am running:

java -Dwebdriver.gecko.driver=chromedriver.exe -jar selenium-server-standalone-3.4.0.jar -role node -hub http://localhost:4444/grid/register -browser browserName=chrome,maxInstances=2 -maxSession 2

this is my test class:

public class TestParallel {

Login login;

//@BeforeMethod(alwaysRun = true)
public SeleniumDriverCore testSetup() throws FileNotFoundException, IOException{
    SeleniumDriverCore driver = new SeleniumDriverCore("config/chromeDriverConfig");
    Properties config = new Properties();
    config.load(new FileInputStream("config/testConfig"));
    this.login = new Login(driver);
    driver.browser.open("https://test.test.xyz");

    driver.browser.maximize();
    driver.waits.waitForPageToLoad();
    return driver;
}

@Test(groups={"parallel"})
public void test_one() throws FileNotFoundException, IOException{
    SeleniumDriverCore driver=testSetup();
    login.navigateToPage(Pages.LOGIN);
    login.assertion.verifyLoginPopupAndTitleDisplayed();
    testCleanup(driver);
}

@Test(groups={"parallel"})
public void test_two() throws FileNotFoundException, IOException{
    SeleniumDriverCore driver=testSetup();
    login.navigateToPage(Pages.LOGIN);
    login.assertion.verifyLoginPopupAndTitleDisplayed();
    testCleanup(driver);
}

@Test(groups={"parallel"})
public void test_three() throws FileNotFoundException, IOException{
    SeleniumDriverCore driver=testSetup();
    login.navigateToPage(Pages.LOGIN);
    login.assertion.verifyLoginPopupAndTitleDisplayed();
    testCleanup(driver);
}

@Test(groups={"parallel"})
public void test_four() throws FileNotFoundException, IOException{
    SeleniumDriverCore driver=testSetup();
    login.navigateToPage(Pages.LOGIN);
    login.assertion.verifyLoginPopupAndTitleDisplayed();
    testCleanup(driver);
}


public void testCleanup(SeleniumDriverCore driver){
    driver.close();
    driver.quit();
}

}

and here is my xml:

<suite name="Ontega - All Tests Mobile" parallel="methods" thread-count="2">
    <test name="Ontega - All Tests Mobile">
        <groups>
            <run>
                <include name="parallel"/>
                <exclude name="open-defects"/>
            </run>
        </groups>
        <packages>
            <package name="tests.*"/>
        </packages>
    </test>
</suite>

when I run the XML, I expect to have my tests to be running on two browsers in two threads at a time, however when I run the XML I get two browser instances running at the first time and then they are incremented and 50% of the tests are failing, as you can see I am trying to instantiate the driver in each of my methods, although it's not how my framework is working, but I am trying to get to the bottleneck of this issue. Any help would be very appreciated Thanks in advance

Answer 1

Here are some ways of doing this in TestNG. You basically manage your webdriver instantiation and cleanup via a @BeforeMethod and a @AfterMethod config methods. So then you would need to decide how would you want to share the created webdriver instance with your @Test method. For that you have three options:

1. You make use of a ThreadLocal variant, because TestNG guarantees to you that it will execute @BeforeMethod, @Test and @AfterMethod all in the same thread.

Here's a sample that shows you this in action

import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.testng.ITestResult;
import org.testng.Reporter;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

public class TestClassSampleUsingThreadLocal {
    private static final ThreadLocal<RemoteWebDriver> drivers = new ThreadLocal<>();

    @BeforeMethod
    public void instantiateBrowser(ITestResult testResult) {
        RemoteWebDriver driver = new ChromeDriver();
        drivers.set(driver);
    }

    @Test(dataProvider = "dp")
    public void testMethod(String url) {
        Reporter.log("Launching the URL [" + url + "] on Thread [" + Thread.currentThread().getId() + "]", true);
        driver().get(url);
        Reporter.log("Page Title :" + driver().getTitle(), true);
    }

    @DataProvider(name = "dp", parallel = true)
    public Object[][] getData() {
        return new Object[][]{
                {"http://www.google.com"}, {"http://www.stackoverflow.com"}, {"http://facebook.com"}
        };
    }

    @AfterMethod
    public void cleanupBrowser() {
        RemoteWebDriver driver = driver();
        driver.quit();
    }

    private RemoteWebDriver driver() {
        RemoteWebDriver driver = drivers.get();
        if (driver == null) {
            throw new IllegalStateException("Driver should have not been null.");
        }
        return driver;
    }

}

2. You can share the webdriver instance via the ITestResult object. Here's a sample that shows that in action.

import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.testng.ITestResult;
import org.testng.Reporter;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

public class TestClassSample {
    private static final String WEBDRIVER = "driver";

    @BeforeMethod
    public void instantiateBrowser(ITestResult testResult) {
        RemoteWebDriver driver = new ChromeDriver();
        testResult.setAttribute(WEBDRIVER, driver);
    }

    @Test(dataProvider = "dp")
    public void testMethod(String url) {
        Reporter.log("Launching the URL [" + url + "] on Thread [" + Thread.currentThread().getId() + "]", true);
        driver().get(url);
        Reporter.log("Page Title :" + driver().getTitle(), true);
    }

    @DataProvider(name = "dp", parallel = true)
    public Object[][] getData() {
        return new Object[][]{
                {"http://www.google.com"},
                {"http://www.stackoverflow.com"},
                {"http://facebook.com"}
        };
    }

    @AfterMethod
    public void cleanupBrowser(ITestResult testResult) {
        RemoteWebDriver driver = driver(testResult);
        driver.quit();
    }

    private RemoteWebDriver driver() {
        return driver(Reporter.getCurrentTestResult());
    }

    private RemoteWebDriver driver(ITestResult testResult) {
        if (testResult == null) {
            throw new IllegalStateException("testResult should have not been null.");
        }
        Object driverObject = testResult.getAttribute(WEBDRIVER);
        if (driverObject == null) {
            throw new IllegalStateException("Driver should have not been null.");
        }
        if (!(driverObject instanceof RemoteWebDriver)) {
            throw new IllegalStateException("Driver is not a valid webdriver object");
        }
        return (RemoteWebDriver) driverObject;
    }
}

3. You extract out the webdriver instantiation and cleanup into a TestNG listener (one that implements a org.testng.IInvokedMethodListener which sets the created webdriver into the ITestResult (as shown in option 2) or into a ThreadLocal (as shown in option 1). You can find more details about this option along with code snippets in my blog post.