Selenium handles ProtocolHandshake error while running tests parallel

Question

I try practicing to execute tests in parallel using TestNG invocationCount and threadPoolSize .

A. I write a all-in-one test like this, and it is successful

@Test(invocationCount = 5, threadPoolSize = 5)
public void testThreadPool() {        
    WebDriver driver = new ChromeDriver();
    driver.get("http://www.google.com");
    driver.findElement(By.name("q")).sendKeys("Amazon");
    driver.quit();*/        
}

=> 5 Chrome browsers are opened at the same time (parallel), and tests are successfully executed.

B. I define my test in @before and @after, and it doesn't work

@BeforeTest
public void setUp() {
   WebDriver driver = driverManager.setupDriver("chrome");
}

@Test(invocationCount = 5, threadPoolSize = 5)
public void testThreadPool() {    
    driver.get("http://www.google.com");
    driver.findElement(By.name("q")).sendKeys("Amazon");            
}

@AfterTest
public void tearDown() {
   driver.quit()
}

=> 1 chrome browser is opened, and it seems it is refreshed 5 times, and at the end, there are 5 Amazon words entered in text field, with the following log message:

[1593594530,792][SEVERE]: bind() failed: Cannot assign requested address (99)
ChromeDriver was started successfully.
Jul 01, 2020 11:08:51 AM org.openqa.selenium.remote.ProtocolHandshake createSession

I understand that, with B, 5 threads use the same object driver, that's why only one chrome is opened. But I don't know how to manage driver object in this case so I can get the same result like in A.

Any idea appreciated.

Answer 1

You can use ThreadLocal class to make your webdriver Threadsafe

private ThreadLocal<WebDriver> webdriver = new ThreadLocal<WebDriver>();

   @BeforeMethod
    public void setUp() {
       webdriver.set(driverManager.setupDriver("chrome"));
    }
    
    @Test(invocationCount = 5, threadPoolSize = 5)
    public void testThreadPool() {    
        webdriver.get().get("http://www.google.com");
        webdriver.get().findElement(By.name("q")).sendKeys("Amazon");            
    }
    
    @AfterMethod
    public void tearDown() {
       webdriver.get().quit()
    }

Edit: You will need to use BeforeMethod/AfterMethod in above context.