无法在Chrome无头模式下运行测试

Question

I am trying to run tests in Chrome headless mode but getting java.lang.NullPointerException

Chrome version: Version 72.0.3626.121 (Official Build) (64-bit)
Selenium version: 3.8.1
Chromedriver version: 2.45.615355

Here is my BaseTest:

public abstract class BaseTest {

public WebDriver driver;

protected abstract String getUrl();

@Before
public void setUp() {
    Log.startLog("Test is Starting...");
    System.setProperty("webdriver.chrome.driver", "src//test//resources//chromedriver");
    ChromeOptions chromeOptions = new ChromeOptions();
    chromeOptions.setHeadless(true);
    WebDriver driver = new ChromeDriver(chromeOptions);
    driver.manage().timeouts().pageLoadTimeout(20, TimeUnit.SECONDS);
    driver.manage().timeouts().implicitlyWait(5, TimeUnit.SECONDS);
    driver.get(getUrl());
}

@After
public void tearDown() {
    Log.endLog("Test is Ending...");
    driver.manage().deleteAllCookies();
    driver.close();
}
}

When I'm running tests, not in headless mode every test works good but in headless mode, I can't even run a simple test to understand if the headless mode is working or not.

Test example:
@Test public void test() { System.out.println(driver.getTitle()); }

Example URL: https://www.wikipedia.org/

UPDATE: I've created new sample project with this code:

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.chrome.ChromeOptions;

public class test {

public static void main(String[] args) {

    System.setProperty("webdriver.chrome.driver", "/Users/alexsomov/Desktop/chromedriver2");

    //Set Chrome Headless mode as TRUE
    ChromeOptions options = new ChromeOptions();
    options.setHeadless(true);

    //Instantiate Web Driver
    WebDriver driver = new ChromeDriver(options);
    driver.get("https://www.google.com/");
    System.out.println("Page title is - " + driver.getTitle());

    driver.close();
}

And bingo, everything works well... Need to figure out why code above from real project doesn't work seems something wrong with BaseTest class and when I run code with debugger I'm getting driver == null , maybe anyone have a solution how I can solve this problem :/

ANSWER The solution was super easy, just need to change 1 string in setUp() method in BaseTest class.

This one:

WebDriver driver = new ChromeDriver(chromeOptions);

change to this:

driver = new ChromeDriver(chromeOptions);

and everything will work.

Answer 1

If you are using linux environment, may be you have to add --no-sandbox as well and also specific window size settings. --no-sandbox is no needed in windows if you set user container properly.

disable-gpu Only on Windows. Other platforms no longer require it. The --disable-gpu flag is a temporary work around for a few bugs.

if(browser.equalsIgnoreCase("HLChrome")){
            //Headless chrome browser and configure
            WebDriverManager.chromedriver().setup();
            ChromeOptions chromeOptions = new ChromeOptions();
            chromeOptions.addArguments("--no-sandbox");
            chromeOptions.addArguments("--headless");
            chromeOptions.addArguments("disable-gpu");
//            chromeOptions.addArguments("window-size=1400,2100"); // linux should be activate
            driver = new ChromeDriver(chromeOptions);

Answer 2

ANSWER The solution was super easy, just need to change 1 string in setUp() method in BaseTest class.

This one:

WebDriver driver = new ChromeDriver(chromeOptions);

change to this:

driver = new ChromeDriver(chromeOptions);

and everything will work.