Docker execution environment in Selenium Java - Test Execution Trace

Test Overview

This test runs a Selenium WebDriver test inside a Docker container. It opens a browser, navigates to a website, clicks a button, and verifies the page title to ensure the test environment works correctly inside Docker.

Test Code - JUnit 5 with Selenium WebDriver

Selenium Java

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeOptions;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertEquals;
import java.net.URL;

public class DockerSeleniumTest {
    private WebDriver driver;

    @BeforeEach
    public void setUp() throws Exception {
        ChromeOptions options = new ChromeOptions();
        options.addArguments("--headless");
        options.addArguments("--no-sandbox");
        options.addArguments("--disable-dev-shm-usage");
        driver = new RemoteWebDriver(new URL("http://localhost:4444/wd/hub"), options);
    }

    @Test
    public void testButtonClickChangesTitle() {
        driver.get("https://example.com");
        WebElement moreInfoLink = driver.findElement(By.cssSelector("a[href='https://www.iana.org/domains/example']"));
        moreInfoLink.click();
        String expectedTitle = "IANA — IANA-managed Reserved Domains";
        assertEquals(expectedTitle, driver.getTitle());
    }

    @AfterEach
    public void tearDown() {
        if (driver != null) {
            driver.quit();
        }
    }
}

Execution Trace - 5 Steps

Step	Action	System State	Assertion	Result
1	Test starts and sets up RemoteWebDriver with ChromeOptions in headless mode connecting to Selenium Grid in Docker at http://localhost:4444/wd/hub	Docker container running Selenium Grid with Chrome browser ready	-	PASS
2	Driver navigates to https://example.com	Browser inside Docker container loads example.com homepage	-	PASS
3	Finds the link with href 'https://www.iana.org/domains/example' and clicks it	Browser navigates to IANA reserved domains page	-	PASS
4	Checks the page title equals 'IANA — IANA-managed Reserved Domains'	Browser page title is 'IANA — IANA-managed Reserved Domains'	assertEquals(expectedTitle, driver.getTitle())	PASS
5	Test finishes and quits the WebDriver session	Browser session closed, Docker container remains running	-	PASS

Failure Scenario

Failing Condition: Selenium Grid Docker container is not running or not reachable at http://localhost:4444/wd/hub

Execution Trace Quiz - 3 Questions

What does the test verify after clicking the link on example.com?

A The page title changes to 'IANA — IANA-managed Reserved Domains'

B The URL remains https://example.com

C The button becomes disabled

D An alert popup appears

Key Result

Always verify that your Docker Selenium Grid container is running and accessible before running tests. Use headless browser mode to run tests smoothly inside Docker without GUI.