Selenium Grid Parallel

Parallel Execution with Selenium Grid

December 3, 2015 by Vaibhav Singhal | 4 comments

• Technology

     Selenium Grid for Parallel Execution

When we say parallel test execution in Selenium is achieved by Selenium Grid than statement is partly incorrect.

1. Testing Framework like testng is used for parallel test execution
2. Selenium Grid is used for execution on Distributed systems in parallel

Selenium Grid Concept

1. In Selenium Grid architecture we have 1 Hub which acts as central controlling authority and connecting nodes. Nodes must be registered to Hub
2. Consider node as port opened on machine (loacal or remote). Each node is capable to opening multiple browsers.
3. On single machine we can have multiple nodes opened
4. Grid Hub decides what tests needs to routed on which node, we can’t control them

Best Practices of Selenium Grid

1. Single machine should open one node only
2. Each node should run only single type of browser
3. We need various driver object for various threads to be run parallely, so create driver as ThreadLocal variable

Let consider an example what we would be achieving in our Grid:

 

 

Start Hub and Nodes

1. Download “Selenium Standalone Server” from “http://www.seleniumhq.org/download/” on all 3 machines
2. Goto machine 1 and open command prompt.
3. Navigate to location where jar is located.
4. Start Hub by command:  java -jar selenium-server-standalone-2.48.2.jar -role hub
5. Open browser and navigate to http://localhost:4444/grid/console and verify hub is started by checking below image.
6. Goto machine 2 and open command prompt
7. Navigate to location where jar is located.
8. Start Node by command: java -Dwebdriver.chrome.driver={path to chromedriver.exe}-jar selenium-server-standalone-2.48.2.jar -role webdriver -hub http://10.1.13.70:4444/grid/register -port 5560 -browser browserName=chrome,maxInstances=2,maxSession=2
9. Goto machine 1 and in browser navigate to http://localhost:4444/grid/console and verify node is started by checking below image.
10. Goto machine 3 and open command prompt.
11. Navigate to location where jar is located.
12. Start Node by command: java -jar selenium-server-standalone-2.48.2.jar -role webdriver -hub http://10.1.13.70:4444/grid/register -port 5557 -browser browserName=firefox,maxInstances=5,maxSession=2
13. Goto machine 1 and in browser navigate to http://localhost:4444/grid/console and verify node is started by checking below image. 
14. Nodes can be opened for various settings like browser, platform, version.
15. Now Selenium Hub and Nodes are created, lets make some @Test and execute them.
16. Make Project on any machine, my project structure as below:
17. Source code for files are given below.
18. Execute testng.xml and execution will start parallely on both machines.

     testng.xml

<?xml version="1.0"encoding="UTF-8"?>
<suite name="Parallel test suite" parallel="classes"thread-count="2">
    <test name="Regression 1">
        <parameter name="myBrowser"value="firefox"/>
        <classes>
            <classname="myPackage.TestParallel"/>
            <classname="myPackage.TestParallel"/>
        </classes>
    </test>
    <test name="Regression 2">
        <parameter name="myBrowser"value="chrome"/>
        <classes>
            <classname="myPackage.TestParallel"/>
            <classname="myPackage.TestParallel"/>
        </classes>
    </test>
 </suite>

package myPackage;
 
import java.net.MalformedURLException;
import java.net.URL;
import java.util.concurrent.TimeUnit;
 
import org.openqa.selenium.Platform;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.remote.DesiredCapabilities;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.testng.annotations.AfterClass;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.Parameters;
 
public class BaseClass {
 
    //ThreadLocal will keep local copy of driver
    public static ThreadLocal<RemoteWebDriver> dr = newThreadLocal<RemoteWebDriver>();
 
    @BeforeTest
    //Parameter will get browser from testng.xml on which browser test to run
    @Parameters("myBrowser")
    public void beforeClass(String myBrowser) throws MalformedURLException{
 
        RemoteWebDriver driver = null;
 
        if(myBrowser.equals("chrome")){
            DesiredCapabilities capability = newDesiredCapabilities().chrome();
            capability.setBrowserName("chrome");
            capability.setPlatform(Platform.WINDOWS);
            driver = newRemoteWebDriver(newURL("http://localhost:4444/wd/hub"), capability);
        }
        elseif(myBrowser.equals("firefox")){
            DesiredCapabilities capability = newDesiredCapabilities().firefox();
            capability.setBrowserName("firefox");
            capability.setPlatform(Platform.WINDOWS);
            driver = newRemoteWebDriver(newURL("http://localhost:4444/wd/hub"), capability);
        }
 
        //setting webdriver
        setWebDriver(driver);
 
        getDriver().manage().window().maximize();
        getDriver().manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
 
    }
 
    public WebDriver getDriver() {
        returndr.get();
    }
 
    public void setWebDriver(RemoteWebDriver driver) {
        dr.set(driver);
    }
 
    @AfterClass
    public void afterClass(){
        getDriver().quit();
        dr.set(null);
 
    }
 
}


package myPackage;
 
import java.net.MalformedURLException;
import java.net.URL;
 
import org.openqa.selenium.By;
import org.openqa.selenium.Platform;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.remote.DesiredCapabilities;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;
 
public class TestParallel extendsBaseClass {
 
    @Test
    public void test_01() throws InterruptedException, MalformedURLException{
        try{
            getDriver().get("http://www.w3schools.com/");
 
            getDriver().findElement(By.xpath("html/body/div[2]/div/a[4]")).click();
 
            //Wait intentially added to show parallelism execution
            Thread.sleep(10000);
 
            getDriver().findElement(By.xpath("//*[@id='gsc-i-id1']")).sendKeys("test");
            Thread.sleep(5000);
 
        }
        catch(Exception e){
            System.out.println(e);
        }
    }
}