Libraries & Frameworks

Development

Advanced 15 Selenium Interview Questions with Coding Examples

1. Selenium Architecture & Core ConceptsQ1: Explain Selenium WebDriver’s architecture in detailAnswer:Selenium WebDriver follows a client-server architecture with these key components:Client Libraries (Language Bindings)Available in Java, Python, C#, JavaScript, etc.Convert test script commands into HTTP requests via JSON Wire Protocol (or W3C WebDriver Protocol)Browser DriversChromeDriver (for Chrome), GeckoDriver (Firefox), etc.Act as intermediaries that translate HTTP requests into browser-specific actionsEach browser has its own driver implementationReal BrowsersReceive commands from their respective driversExecute actions like click(), sendKeys() nativelyVisual Flow:Test Script → Language Binding → JSON Wire Protocol → Browser Driver → Actual BrowserKey Protocols:Legacy: JSON Wire Protocol (Selenium 3)Modern: W3C WebDriver Protocol (Selenium 4+)Q2: How does Selenium interact with headless browsers?Answer with Technical Details:Headless browsers execute without GUI for faster performance. Implementation:javaChromeOptions options = new ChromeOptions();
options.addArguments(“–headless”, “–disable-gpu”);
// ‘–disable-gpu’ avoids potential rendering issues
options.addArguments(“–window-size=1920,1080”);
// Sets viewport size for consistent rendering

WebDriver driver = new ChromeDriver(options);Why Use Headless?2-3x faster execution (no UI rendering overhead)Ideal for CI/CD pipelines (Jenkins, GitHub Actions)Better for Linux servers without GUI environmentsLimitations:Harder to debug (no visual feedback)Some anti-bot systems detect headless modeAlternatives:Firefox Headless: options.addArguments(“–headless”)PhantomJS (deprecated)2. Advanced WebDriver TechniquesQ3: How would you handle a StaleElementReferenceException?Deep Dive Solution:This occurs when the DOM changes after element location but before interaction. Robust handling:javapublic void safeClick(By locator, int maxRetries) {
int attempts = 0;
while (attempts < maxRetries) {
try {
driver.findElement(locator).click();
break;
} catch (StaleElementReferenceException e) {
attempts++;
if (attempts == maxRetries) throw e;
// Optional: Add small wait
try { Thread.sleep(200); } catch (InterruptedException ie) {}
}
}
}

// Usage:
safeClick(By.id(“dynamic-button”), 3);Root Causes:Page refresh/AJAX updatesDOM re-rendering (common in React/Angular apps)Navigation between pagesPrevention Strategies:Use Page Object Model with re-initialized elementsImplement custom ExpectedConditions for dynamic elementsPrefer relative locators over absolute XPathsQ4: Automate file download without third-party toolsComprehensive Solution:java// Chrome Configuration
ChromeOptions options = new ChromeOptions();

// Set download directory (escape backslashes in Windows)
String downloadPath = “C:\test_downloads”;
options.setExperimentalOption(“prefs”, Map.of(
“download.default_directory”, downloadPath,
“download.prompt_for_download”, false,
“download.directory_upgrade”, true,
“safebrowsing.enabled”, true // Disables security warnings
));

// Disable PDF viewer to force downloads
options.addArguments(“–disable-extensions”);
options.addArguments(“–disable-print-preview”);

WebDriver driver = new ChromeDriver(options);

// Trigger download
driver.get(“https://example.com/file.pdf”);

// Verification (Java 11+)
long waitTime = 30; // seconds
Path file = Path.of(downloadPath, “file.pdf”);
boolean isDownloaded = Files.waitUntilExists(file, waitTime);Key Considerations:Browser-specific configurations (Chrome vs Firefox)Network speed impacts download completionCleanup downloaded files between testsEdge Cases:Handling “Save As” dialogs (requires OS-level automation)Large file timeouts3. Framework Design & PatternsQ5: Explain the Hybrid Framework in SeleniumDetailed Architecture:Component Breakdown:Page Object Model (POM)Each page as a Java class (LoginPage.java)Elements stored as @FindBy annotationsMethods for page actions (login(String user, String pass))Data-Driven TestingExternalize test data to JSON/ExcelTestNG @DataProvider feeds multiple datasetsjava@DataProvider
public Object[][] loginData() {
return new Object[][] {
{“user1”, “pass123”},
{“user2”, “pass456”}
};
}Keyword-DrivenNon-technical test cases in Excel:ActionLocatorValueclickid=submit-btntypename=emailtest@demo.comAdvantages:60-70% less code maintenanceEnables parallel executionBusiness-readable test cases4. Performance OptimizationQ6: How to reduce flaky tests?Proven Strategies with Examples:Smart Waitsjavapublic WebElement waitForClickable(By locator, int timeout) {
return new WebDriverWait(driver, Duration.ofSeconds(timeout))
.until(ExpectedConditions.elementToBeClickable(locator));
}Retry Mechanismjava@Test(retryAnalyzer = RetryAnalyzer.class)
public void flakyTest() { … }Locator StabilityAvoid XPaths like //div[3]/button[1]Prefer CSS selectors: button.submit-btnTest IsolationClear cookies between testsUse fresh user sessionsMonitoring:Track flakiness percentageQuarantine unstable tests5. Real-World ScenariosQ7: Automate testing for a real-time stock dashboardSolution Architecture:Implementation Steps:WebSocket Testingjava// Using Java-WebSocket library
WebSocketClient client = new WebSocketClient(new URI(“wss://stocks”)) {
@Override
public void onMessage(String message) {
// Parse JSON and assert values
}
};
client.connect();Visual RegressionjavaBufferedImage current = new AShot()
.shootingStrategy(ShootingStrategies.viewportPasting(1000))
.takeScreenshot(driver)
.getImage();
ImageIO.write(current, “PNG”, new File(“current.png”));Database AssertionsjavaStatement stmt = dbConnection.createStatement();
ResultSet rs = stmt.executeQuery(“SELECT price FROM stocks”);
assertTrue(rs.next());
assertEquals(150.25, rs.getDouble(“price”), 0.01);Challenges:High-frequency updatesTime synchronizationDynamic chart renderingQ8: Parallel Test Execution Implementation (Deep Dive)TestNG Parallel Execution Explained:The TestNG XML configuration enables parallel execution at multiple levels:xml<suite name=”ParallelSuite” parallel=”tests” thread-count=”4″ configfailurepolicy=”continue”>
<!– Suite-level parallel execution –>
<test name=”ChromeTests” parallel=”classes” thread-count=”2″>
<parameter name=”browser” value=”chrome”/>
<classes>
<class name=”com.tests.LoginTest”/>
<class name=”com.tests.CheckoutTest”/>
</classes>
</test>
<test name=”FirefoxTests”>
<parameter name=”browser” value=”firefox”/>
<packages>
<package name=”com.module1.tests.*”/>
</packages>
</test>
</suite>Key Attributes:parallel=”tests|classes|methods|instances”:tests: Parallel test tagsclasses: Parallel test classesmethods: Parallel test methodsthread-count: Maximum concurrent threadsconfigfailurepolicy=”continue”: Continue execution after failed configurationsImplementation Best Practices:Use @BeforeClass for browser initializationMake tests independent with proper cleanupUtilize ThreadLocal<WebDriver> for thread-safe driver managementBalance thread count with system resources (optimal is CPU cores × 1.5)Advanced Scenario: Cross-Browser Parallelismxml<test name=”CrossBrowser”>
<methods>
<include name=”testLogin” invocation-count=”3″>
<parameter name=”browser” value=”chrome”/>
<parameter name=”browser” value=”firefox”/>
<parameter name=”browser” value=”edge”/>
</include>
</methods>
</test>Q9: BDD Framework Advantages (Expanded)Cucumber/Gherkin Workflow:textFeature: Login functionality
Scenario: Successful login
Given I navigate to login page
When I enter valid “testuser” and “Pass123”
Then I should see dashboardTechnical Benefits:Living Documentation:Feature files serve as always-updated specsAutomated generation of documentation (e.g., with Pickles)Step Reusability:java@When(“I enter valid {string} and {string}”)
public void enterCredentials(String user, String pass) {
loginPage.enterCredentials(user, pass);
}CI/CD Integration:JSON/HTML reports integration with JenkinsTag-based execution (@smoke, @regression)Test Data Management:Scenario outlines with examples tables:textExamples:
| username | password |
| user1 | Password1! |
| user2 | Password2! |Collaboration Impact:Product owners can validate scenariosDevelopers and QA share step definitionsReduces misinterpretation of requirementsQ10: Flaky Test Solutions (Comprehensive Guide)Root Cause Analysis Matrix:CauseSolutionCode ExampleElement StalenessRe-locate element before interactionnew WebElementProxy(driver, locator).click()Timing IssuesSmart waits with custom conditionswait.until(d -> element.isDisplayed())Test Order DependencyIndependent test data@BeforeMethod void cleanCookies()Environment VarianceDockerized consistent environmentsdocker-compose up selenium-hubAdvanced Techniques:Retry Analyzer:javapublic class RetryAnalyzer implements IRetryAnalyzer {
private int count = 0;
private static final int MAX_RETRY = 2;

public boolean retry(ITestResult result) {
return count++ < MAX_RETRY &&
result.getThrowable() instanceof StaleElementReferenceException;
}
}Element State Monitoring:javapublic void safeClick(By locator) {
wait.until(d -> {
try {
WebElement el = d.findElement(locator);
return el.isDisplayed() && el.isEnabled();
} catch (StaleElementReferenceException e) {
return false;
}
}).click();
}Q11: Test Speed Optimization (Professional Approach)Performance Benchmarking Table:TechniqueSpeed GainImplementationHeadless Mode40-60% fasteroptions.addArguments(“–headless”)CDP Mocking30% faster API callsdevTools.send(Network.enable())Disable Images25% faster loadsprefs.put(“profile.managed_default_content_settings.images”, 2)DOM Freeze DetectionPrevent wasted waits((JavascriptExecutor)driver).executeScript(“return document.readyState”)Chrome DevTools Protocol Example:javaDevTools devTools = ((ChromeDriver)driver).getDevTools();
devTools.createSession();
devTools.send(Network.enable(Optional.empty(), Optional.empty(), Optional.empty()));
devTools.send(Network.emulateNetworkConditions(
false, 100, 5000, 2000,
Optional.of(ConnectionType.CELLULAR3G)
);Advanced Configurations:javaChromeOptions options = new ChromeOptions();
options.setCapability(“goog:loggingPrefs”, new LoggingPreferences());
options.addArguments(“–disable-extensions”);
options.addArguments(“–disable-notifications”);
options.addArguments(“–disable-web-security”);
options.setExperimentalOption(“excludeSwitches”,
new String[]{“enable-automation”});Q12: Jenkins Integration (Production-Grade Setup)Pipeline Script Example:groovypipeline {
agent any
stages {
stage(‘Checkout’) {
steps {
git branch: ‘main’, url: ‘https://github.com/your/repo.git’
}
}
stage(‘Test’) {
parallel {
stage(‘Chrome’) {
steps {
sh “mvn test -Dbrowser=chrome -Dgroups=smoke”
}
}
stage(‘Firefox’) {
steps {
sh “mvn test -Dbrowser=firefox -Dgroups=smoke”
}
}
}
}
stage(‘Report’) {
steps {
allure includeProperties: false, jdk: ”, results: [[path: ‘target/allure-results’]]
}
}
}
post {
always {
archiveArtifacts artifacts: ‘target/surefire-reports/**/*’, fingerprint: true
}
}
}Key Plugins:Allure Reporting: Trend analysis and historical comparisonsTest Results Analyzer: Identify flaky testsBuild Pipeline: Visualize test stagesSlack Notification: Alert on failuresQ13: Dockerized Selenium (Enterprise Architecture)Production-Ready docker-compose.yml:yamlversion: ‘3.8’
services:
hub:
image: selenium/hub:4.1.0
ports:
– “4442:4442” # Grid console
– “4443:4443” # Live sessions
environment:
– SE_EVENT_BUS_HOST=hub
– SE_NODE_MAX_SESSIONS=5
deploy:
resources:
limits:
cpus: ‘1’
memory: 2G

chrome:
image: selenium/node-chrome:4.1.0
shm_size: 2gb
environment:
– SE_EVENT_BUS_HOST=hub
– SE_NODE_MAX_SESSIONS=3
depends_on:
– hub
volumes:
– /dev/shm:/dev/shm # Critical for Chrome stabilityScaling with Kubernetes:bashkubectl create deployment selenium-hub –image=selenium/hub
kubectl scale deployment selenium-node –replicas=5Best Practices:Use –shm-size for Chrome containersImplement health checks with SE_NODE_HEALTHCHECK_INTERVALConfigure session timeout with SE_NODE_SESSION_TIMEOUTQ14: CAPTCHA Testing Strategies (Compliance-Friendly)Enterprise Solutions:Test Environment Bypass:Development flag: ?disable_captcha=trueMock service response:java@Mock
CaptchaService captchaService;
when(captchaService.verify(anyString())).thenReturn(true);Third-Party Services:2Captcha API integrationAnti-Captcha services with Selenium bindingsLegal Compliance:Whitelist test IPs in CAPTCHA configurationUse enterprise bypass tokensAutomation Workaround Example:javapublic void bypassCaptcha() {
if (isTestEnvironment()) {
driver.executeScript(
“document.getElementById(‘captcha’).value = ‘BYPASSED'”);
} else {
solveRealCaptcha();
}
}Q15: Real-Time Dashboard Testing (Financial Grade)WebSocket Testing Framework:javapublic class StockTickerTest {
private WebSocketClient client;

@BeforeMethod
public void connect() throws URISyntaxException {
client = new WebSocketClient(new URI(“wss://api.stock.com”)) {
@Override
public void onMessage(String message) {
StockData data = new Gson().fromJson(message, StockData.class);
assertTrue(data.getPrice() > 0);
}
};
client.connect();
}

@Test
public void testPriceUpdates() {
driver.findElement(By.id(“refresh”)).click();
await().atMost(5, SECONDS).untilAsserted(() -> {
assertNotNull(lastMessage);
});
}
}Visual Regression Pipeline:Baseline capture on releasePixel-by-pixel comparison with tolerance thresholdsDynamic element masking (timestamps, moving averages)AI-based anomaly detection (Applitools Eyes)Data Validation Approach:sqlSELECT stock_symbol, COUNT(*)
FROM price_updates
WHERE timestamp > NOW() – INTERVAL ‘1 minute’
GROUP BY stock_symbol
HAVING COUNT(*) < 10; — Expecting 10+ updates per minuteConclusionThese detailed explanations demonstrate deep technical understanding that interviewers value. These expanded explanations provide the technical depth and real-world implementation details that senior automation engineers having experience 4 to 10 years need during interviews.Pro Tip: Always relate answers to your project experience during interviews.#Selenium #Testing #InterviewPrep 🚀

Development

How to Build a Custom Visual Testing Tool with Selenium: A Practical Guide

IntroductionVisual testing is crucial for ensuring UI consistency across releases. While commercial tools exist, sometimes you need a custom solution tailored to your specific needs. This guide walks you through creating your own visual testing tool using Selenium and Python.Table of ContentsIntroductionWhy Build a Custom Visual Testing Tool?Core ComponentsImplementation GuideAdvanced FeaturesIntegration & ScalingReporting & AnalysisCommon Challenges & SolutionsLimitations & ConsiderationsConclusion & Next StepsWhy Build a Custom Solution?Specific requirements not met by commercial toolsCost savings for simple projectsComplete control over comparison logicLearning opportunity about image processingCore Components1. Screenshot Capture with Seleniumpythonfrom selenium import webdriver
import os

def capture_screenshot(url, filename):
“””Capture screenshot of a webpage”””
driver = webdriver.Chrome()
driver.get(url)

# Ensure screenshot directory exists
os.makedirs(“screenshots”, exist_ok=True)
screenshot_path = f”screenshots/{filename}”

driver.save_screenshot(screenshot_path)
driver.quit()
return screenshot_path2. Image Comparison Enginepythonfrom PIL import Image, ImageChops
import math

def compare_images(baseline_path, current_path, diff_path=None, threshold=0.95):
“””
Compare two images with similarity threshold
Returns: (is_similar, similarity_score)
“””
baseline = Image.open(baseline_path).convert(‘RGB’)
current = Image.open(current_path).convert(‘RGB’)

# Check dimensions
if baseline.size != current.size:
return False, 0

# Calculate difference
diff = ImageChops.difference(baseline, current)
diff_pixels = sum(
sum(1 for pixel in diff.getdata() if any(c > 0 for c in pixel))
)
total_pixels = baseline.size[0] * baseline.size[1]
similarity = 1 – (diff_pixels / total_pixels)

# Save diff image if needed
if diff_path and diff_pixels > 0:
diff.save(diff_path)

return similarity >= threshold, similarity3. Baseline Management Systempythonimport json
from datetime import datetime

class BaselineManager:
def __init__(self, baseline_dir=”baselines”):
self.baseline_dir = baseline_dir
os.makedirs(baseline_dir, exist_ok=True)

def save_baseline(self, name, image_path):
“””Save a new baseline with metadata”””
timestamp = datetime.now().isoformat()
baseline_path = f”{self.baseline_dir}/{name}.png”
metadata = {
“created”: timestamp,
“source”: image_path
}

# Save image
Image.open(image_path).save(baseline_path)

# Save metadata
with open(f”{baseline_dir}/{name}.json”, ‘w’) as f:
json.dump(metadata, f)

return baseline_pathAdvanced Features1. Region-Specific Comparisonpythondef compare_regions(baseline_path, current_path, regions, threshold=0.95):
“””
Compare specific regions of images
regions: List of (x, y, width, height) tuples
“””
baseline = Image.open(baseline_path)
current = Image.open(current_path)
results = []

for region in regions:
x, y, w, h = region
baseline_crop = baseline.crop((x, y, x+w, y+h))
current_crop = current.crop((x, y, x+w, y+h))

is_similar, score = compare_images(
baseline_crop, current_crop, threshold=threshold
)
results.append((region, is_similar, score))

return results2. Dynamic Content Maskingpythondef mask_dynamic_regions(image_path, regions, output_path=None):
“””
Mask dynamic content regions with black rectangles
“””
img = Image.open(image_path)
draw = ImageDraw.Draw(img)

for region in regions:
x, y, w, h = region
draw.rectangle((x, y, x+w, y+h), fill=’black’)

if output_path:
img.save(output_path)
return imgPutting It All Togetherpythondef run_visual_test(url, test_name, threshold=0.95):
“””Complete visual test workflow”””
# Setup
bm = BaselineManager()
current_path = capture_screenshot(url, f”current_{test_name}.png”)

# Check if baseline exists
baseline_path = f”baselines/{test_name}.png”
if not os.path.exists(baseline_path):
print(f”Creating new baseline for {test_name}”)
bm.save_baseline(test_name, current_path)
return True

# Compare images
diff_path = f”diffs/diff_{test_name}.png”
is_similar, score = compare_images(
baseline_path, current_path, diff_path, threshold
)

# Generate report
report = {
“test_name”: test_name,
“passed”: is_similar,
“similarity_score”: score,
“diff_image”: diff_path if not is_similar else None,
“timestamp”: datetime.now().isoformat()
}

return reportHandling Common ChallengesCross-Browser VariationsCreate separate baselines per browserAdjust similarity thresholds per browserResponsive TestingTest at multiple viewport sizesUse device emulation in SeleniumTest MaintenanceImplement baseline versioningAdd approval workflow for new baselinesPerformance OptimizationCache screenshotsParallelize testsIntegration with Test Frameworkspythonimport unittest

class VisualTestCase(unittest.TestCase):
@classmethod
def setUpClass(cls):
cls.bm = BaselineManager()

def test_homepage_layout(self):
report = run_visual_test(
“https://example.com”,
“homepage_desktop”,
threshold=0.98
)
self.assertTrue(report[‘passed’],
f”Visual regression detected. Similarity: {report[‘similarity_score’]}”)Reporting and Analysispythondef generate_html_report(test_reports):
“””Generate visual test HTML report”””
html = “””
<html><head><title>Visual Test Report</title></head>
<body><h1>Visual Test Results</h1>
<table border=”1″>
<tr>
<th>Test</th>
<th>Status</th>
<th>Similarity</th>
<th>Diff</th>
</tr>
“””

for report in test_reports:
status = “PASS” if report[‘passed’] else “FAIL”
color = “green” if report[‘passed’] else “red”
diff_link = f'<a href=”{report[“diff_image”]}”>View</a>’ if report[“diff_image”] else “None”

html += f”””
<tr>
<td>{report[‘test_name’]}</td>
<td style=”color:{color}”>{status}</td>
<td>{report[‘similarity_score’]:.2%}</td>
<td>{diff_link}</td>
</tr>
“””

html += “</table></body></html>”
return htmlScaling Your SolutionParallel ExecutionUse Selenium GridImplement multiprocessingBaseline ManagementStore baselines in cloud storageAdd metadata taggingCI/CD IntegrationAdd as a test step in your pipelineConfigure failure thresholdsLimitations to ConsiderMaintenance overhead for baseline updatesBrowser-specific rendering differencesPerformance impact of image processingLimited to pixel comparison (no semantic understanding)ConclusionBuilding a custom visual testing tool gives you flexibility but requires careful implementation. Start small with critical pages, then expand as needed. Consider these enhancements:Add machine learning for smarter diff detectionImplement cloud storage for baselinesCreate a dashboard for trend analysisAdd support for component-level testingRemember that commercial tools might become more cost-effective as your needs grow, but a custom solution can be perfect for specific requirements.

Development

How to Perform Visual Testing Using Selenium: A Detailed Guide

Visual testing is an essential part of UI validation, ensuring that web applications appear and function as intended across different browsers, devices, and screen resolutions. While Selenium is primarily used for functional testing, it can also be leveraged for visual regression testing with the help of additional tools and libraries.In this blog, we’ll explore how to perform visual testing using Selenium, covering key concepts, tools, and step-by-step implementation.Table of ContentsWhat is Visual Testing?Why Use Selenium for Visual Testing?Tools for Visual Testing with SeleniumStep-by-Step Guide to Perform Visual TestingPrerequisitesSetting Up Selenium WebDriverCapturing ScreenshotsComparing ScreenshotsGenerating Test ReportsGeneral Steps to Perform Visual TestingBest Practices for Visual TestingConclusion1. What is Visual Testing?Visual testing (or visual regression testing) compares screenshots of a web application’s UI against baseline images to detect unintended visual changes. It helps identify issues like:Layout shiftsBroken fonts or imagesOverlapping elementsResponsive design failuresUnlike functional testing, which verifies behavior, visual testing ensures the UI looks correct.2. Why Use Selenium for Visual Testing?Selenium WebDriver is widely used for automating browser interactions. While it doesn’t natively support visual comparisons, it can:Capture screenshots of web pages.Integrate with visual testing libraries (e.g., Applitools, Percy, or OpenCV).Run cross-browser tests to ensure consistency.3. Tools for Visual Testing with SeleniumHere are some popular tools for visual testing with Selenium:ToolDescriptionApplitoolsAI-powered visual testing with automatic baseline management.PercyCloud-based visual testing by BrowserStack.AShotJava-based screenshot comparison library.OpenCVOpen-source computer vision library for image processing.SikuliXUses image recognition for UI testing.We’ll use AShot (for Java) and Pillow (for Python) in this guide.4. Step-by-Step Guide to Perform Visual TestingPrerequisites Java/Python installedSelenium WebDriverMaven/Gradle (for Java) or pip (for Python)A testing framework (JUnit/TestNG for Java, pytest for Python)Setting Up Selenium WebDriverJava (Maven)xml<dependency>
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-java</artifactId>
<version>4.10.0</version>
</dependency>
<dependency>
<groupId>ru.yandex.qatools.ashot</groupId>
<artifactId>ashot</artifactId>
<version>1.5.4</version>
</dependency>Python (pip)bashpip install selenium pillow opencv-pythonCapturing ScreenshotsJava (Using AShot)javaimport org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import ru.yandex.qatools.ashot.AShot;
import ru.yandex.qatools.ashot.Screenshot;
import javax.imageio.ImageIO;
import java.io.File;

public class VisualTest {
public static void main(String[] args) throws Exception {
WebDriver driver = new ChromeDriver();
driver.get(“https://example.com”);

// Capture screenshot
Screenshot screenshot = new AShot().takeScreenshot(driver);
ImageIO.write(screenshot.getImage(), “PNG”, new File(“screenshot.png”));

driver.quit();
}
}Python (Using Pillow)pythonfrom selenium import webdriver
from PIL import Image

driver = webdriver.Chrome()
driver.get(“https://example.com”)

# Capture screenshot
driver.save_screenshot(“screenshot.png”)
driver.quit()Comparing ScreenshotsJava (Using AShot)javaimport java.awt.image.BufferedImage;
import javax.imageio.ImageIO;

public class ImageComparator {
public static boolean compareImages(String img1Path, String img2Path) throws Exception {
BufferedImage img1 = ImageIO.read(new File(img1Path));
BufferedImage img2 = ImageIO.read(new File(img2Path));

if (img1.getWidth() != img2.getWidth() || img1.getHeight() != img2.getHeight()) {
return false;
}

for (int y = 0; y < img1.getHeight(); y++) {
for (int x = 0; x < img1.getWidth(); x++) {
if (img1.getRGB(x, y) != img2.getRGB(x, y)) {
return false;
}
}
}
return true;
}
}Python (Using OpenCV)pythonimport cv2
import numpy as np

def compare_images(img1_path, img2_path):
img1 = cv2.imread(img1_path)
img2 = cv2.imread(img2_path)

if img1.shape != img2.shape:
return False

difference = cv2.subtract(img1, img2)
return not np.any(difference)Generating Test Reports Use testing frameworks like TestNG (Java) or pytest (Python) to log results:java@Test
public void testVisualComparison() throws Exception {
Assert.assertTrue(ImageComparator.compareImages(“expected.png”, “actual.png”));
}5. General Steps When Using a Visual Testing PlatformWhen using a dedicated visual testing platform (e.g., Percy, Applitools), follow these steps:1. Set Up Your Selenium ProjectEnsure you have a working Selenium automation framework in your preferred language (Java, Python, C#, JavaScript, etc.).2. Integrate the Visual Testing SDKInstall the SDK provided by your chosen platform. Examples:Python (Percy)bashpip install percy-seleniumJavaScript (Percy)bashnpm install @percy/selenium-webdriver3. Capture BaselinesThe first time you run visual tests, the tool captures “baseline” screenshots (expected UI state).Example (Python with Percy)pythonfrom selenium import webdriver
from percy import percy_snapshot

driver = webdriver.Chrome()
driver.get(“https://your-application.com”)
percy_snapshot(driver, “Homepage – Initial State”)

# Perform actions
driver.get(“https://your-application.com/some-other-page”)
percy_snapshot(driver, “Another Page – After Interaction”)
driver.quit()4. Run Tests and CompareIn subsequent runs, the tool compares new screenshots against baselines.5. Review and Approve ChangesDifferences are highlighted in a dashboard.Approve intentional changes (updates baseline).Flag unintended changes as bugs.6. Integrate with CI/CDRun visual tests in pipelines (e.g., GitHub Actions, Jenkins) for continuous feedback.6. Best Practices for Visual Testing1. Strategic SnapshottingFocus on critical UI components (headers, forms, key interactions) rather than capturing every element.Prioritize page layouts and areas prone to visual regressions (e.g., responsive breakpoints).2. Handle Dynamic ContentIgnore/Mask dynamic elements (e.g., ads, timestamps, user-generated content) to avoid false positives.Use tools like Percy’s ignoreRegions or Applitools’ ignoreDisplacements to exclude volatile areas.3. Maintain BaselinesReview baselines regularly and update them only for intentional UI changes.Store baselines in version control (e.g., Git) to track historical changes.4. Cross-Browser & Device TestingTest across multiple browsers (Chrome, Firefox, Safari) and viewport sizes (desktop, tablet, mobile).Leverage cloud platforms (e.g., BrowserStack, Sauce Labs) for broader coverage.5. Configure Thresholds & SensitivityAdjust pixel-matching thresholds to balance between catching bugs and reducing noise.Example: Set a 5% difference threshold for minor anti-aliasing changes.6. Component-Level TestingTest isolated UI components (buttons, modals, cards) for design system consistency.Tools like Storybook + Percy enable visual testing of individual components.Bonus: CI/CD IntegrationRun visual tests automatically in pipelines (GitHub Actions, Jenkins) to catch regressions early.Fail builds on critical visual deviations but allows manual review for minor changes.7. ConclusionVisual testing with Selenium helps ensure UI consistency across releases. While Selenium itself doesn’t support visual comparisons, integrating tools like AShot, OpenCV, or Applitools makes it possible.By following this guide, you can implement automated visual regression testing and catch UI bugs early in development.🚀 Next Steps: Try integrating visual testing into your CI/CD pipeline for seamless validation!Have questions? Drop them in the comments!#Selenium #VisualTesting #Automation #QA

Testing in Open Source Projects

This is a bit of a general question. I’m trying to practice my testing skills and perhaps get some better experience with manual testing mature applications. In particular, I’m interested in desktop applications. One good place to do this is with open source projects, particularly those in need of dedicated/semi-dedicated testers. While I know every open source project has its own culture around it, with differing levels of maturity, are there any general tips for OSS testing?

mehrancodes/laravel-harbor

A CLI tool to Quickly create On-Demand preview environment for your apps. Source: Read More 

Development

JMeter Tutorial: An End-to-End Guide

Modern web and mobile applications live or die by their speed, stability, and scalability. Users expect sub-second responses, executives demand uptime, and DevOps pipelines crank out new builds faster than ever. In that high-pressure environment, performance testing is no longer optional; it is the safety net that keeps releases from crashing and brands from burning.
The post JMeter Tutorial: An End-to-End Guide appeared first on Codoid.

Development

AI Workbenches Powering the Next Era of Underwriting | Don’t Catch Up. Leap Ahead

The blog discusses how an AI-powered underwriting workbench streamlines insurance operations by centralizing risk tools, data, and workflows. It enhances decision accuracy, supports automation, and delivers faster, more consistent underwriting outcomes. Insurers can boost efficiency and stay compliant in a complex digital environment with built-in machine learning and real-time analytics.
The post AI Workbenches Powering the Next Era of Underwriting | Don’t Catch Up. Leap Ahead first appeared on TestingXperts.

Digital Accessibility Is Rising: Here’s How APAC and LATAM Are Leading the Shift

The blog discusses how accessibility laws in APAC and Latin America are evolving, making compliance a business-critical need. It also explores regional legal updates and how AI-powered accessibility testing helps ensure inclusion, reduce risk and support ethical, user-friendly design.
The post Digital Accessibility Is Rising: Here’s How APAC and LATAM Are Leading the Shift first appeared on TestingXperts.

Before and After Suite in TestNG

What is the notion of Suite in Before/After Suite annotation? Unlike Before/After Class and Method, I never had to use them. Suite I think can’t be the same thing as Java package, since classes with @Test annotations can be put in different packages. Is that so?

Development

PayHere for Laravel

Laravel PayHere is a third-party payment gateway plugin for Laravel. The post PayHere for Laravel appeared first on Laravel News.…

Mastering Your Smartphone: 10 Features You Didn’t Know Existed

In today’s world, smartphones are indispensable, yet most users barely scratch the surface of what their devices can do. Beyond the usual calls, texts, and social media scrolling, there’s a treasure trove of hidden features designed to make your life easier and more productive. Let’s explore 10 amazing smartphone features you probably didn’t know existed!1. Customizable Back Tap GesturesWhat it does: Many modern smartphones, like iPhones and Android devices, have a “back tap” feature. This lets you perform actions like taking a screenshot or opening an app by tapping the back of your phone.How to activate:On iPhone: Go to Settings > Accessibility > Touch > Back Tap and assign actions to double or triple taps.On Android: Check if your device supports similar gestures under Gestures in the Settings menu.2. Wi-Fi Password SharingWhat it does: Forget typing out long Wi-Fi passwords. Share your Wi-Fi access instantly with nearby devices.How to use:On iPhone: When another iPhone is nearby and tries to join the network, a prompt will appear on your device to share the password.On Android: Go to Wi-Fi Settings, select your network, and tap Share QR Code for others to scan.3. Built-In Document ScannerWhat it does: Your smartphone’s camera can double as a document scanner, eliminating the need for separate apps.How to use:On iPhone: Open the Notes app, create a new note, and tap the camera icon to select Scan Documents.On Android: Use Google Drive’s Scan option under the “+” button.4. Digital Wellbeing ToolsWhat it does: Monitor and manage your screen time to promote healthier smartphone usage habits.How to use:On Android: Go to Settings > Digital Wellbeing & Parental Controls.On iPhone: Access Settings > Screen Time to view usage stats and set app limits.5. One-Handed ModeWhat it does: Struggling to use your phone with one hand? Shrink your screen for easier navigation.How to activate:On Android: Go to Settings > Gestures > One-Handed Mode.On iPhone: Enable Reachability under Settings > Accessibility > Touch and swipe down on the bottom edge of the screen.6. Text Replacement ShortcutsWhat it does: Save time by creating shortcuts for frequently used phrases.How to set up:On iPhone: Go to Settings > General > Keyboard > Text Replacement.On Android: Find similar options under Settings > Languages & Input > Personal Dictionary.7. Hidden Battery Health InformationWhat it does: Check your battery’s performance to determine if it needs servicing.How to check:On iPhone: Go to Settings > Battery > Battery Health.On Android: Use the Dialer Code ☎︎#☎︎#4636#☎︎#☎︎** (varies by manufacturer).8. Emergency SOS ShortcutWhat it does: Quickly contact emergency services by pressing a button combination.How to activate:On iPhone: Press the side button five times or hold the side and volume buttons.On Android: Set up SOS under Settings > Safety & Emergency.9. Augmented Reality (AR) MeasurementsWhat it does: Measure objects and spaces in real-time using your phone’s AR capabilities.How to use:On iPhone: Open the Measure app.On Android: Download Google’s Measure app if it’s not pre-installed.10. Live CaptioningWhat it does: Automatically generate captions for videos, podcasts, and even calls in real-time.How to enable:On Android: Go to Settings > Accessibility > Live Caption.On iPhone: Use Live Captions (Beta) under Settings > Accessibility.Final ThoughtsYour smartphone is a powerhouse of features waiting to be discovered. By leveraging these hidden gems, you can unlock new levels of convenience and productivity. Explore these features today, and you might find your device more indispensable than ever!

Development

Top 5 Free Apps That Will Change Your Life

In today’s fast-paced digital world, apps can transform how we manage our time, stay healthy, and even learn new skills. With thousands of apps to choose from, it can be overwhelming to find the right ones that genuinely make a difference in our lives. Here’s a curated list of the top 5 free apps in 2025 that can simplify your day, enhance productivity, and add a touch of convenience to your daily routine. Let’s dive in!1. Notion – The Ultimate Productivity ToolWhy it’s life-changing: Notion is an all-in-one workspace where you can write, plan, collaborate, and organize. Whether you’re a student managing assignments, a professional planning projects, or someone who loves journaling, Notion is perfect for you.Key Features:Customizable templates for notes, task lists, calendars, and databases.Collaboration tools for sharing projects with others.Integration with apps like Google Drive, Slack, and Trello.How to get started: Download the app on your device, sign up for a free account, and explore the pre-designed templates to suit your needs. Start small by creating a simple to-do list or a daily planner.2. Duolingo – Your Personal Language CoachWhy it’s life-changing: Learning a new language has never been easier or more fun. Duolingo turns language learning into a game with bite-sized lessons and rewards for daily practice. Perfect for beginners or anyone looking to brush up on their skills.Key Features:Over 40 languages to choose from, including Spanish, French, and Japanese.Gamified learning with levels, streaks, and achievements.Speech recognition to improve your pronunciation.How to get started: Choose the language you’ve always wanted to learn, set a daily goal, and commit just 10 minutes a day. The app’s AI will personalize lessons based on your progress.3. MyFitnessPal – Your Health CompanionWhy it’s life-changing: Staying healthy doesn’t have to be complicated. MyFitnessPal helps you track your food intake, exercise, and overall wellness. It’s like having a personal nutritionist and fitness coach in your pocket.Key Features:Extensive database of foods to track calories and nutrients.Integration with fitness apps and devices like Fitbit.Customizable goals for weight loss, muscle gain, or maintenance.How to get started: Enter your fitness goals, start logging your meals and exercises, and let the app guide you towards healthier habits. The built-in barcode scanner makes food tracking effortless.4. Pocket – Your Knowledge VaultWhy it’s life-changing: Pocket lets you save articles, videos, and other content for later reading. It’s perfect for anyone who loves to learn but doesn’t have time to consume everything immediately.Key Features:Offline access to saved content.Personalized recommendations based on your interests.A distraction-free reading experience.How to get started: Install the browser extension or app, and save anything you find interesting with a single click. Use your commute or downtime to catch up on your saved content.5. Calm – Your Gateway to RelaxationWhy it’s life-changing: In a world full of stress and noise, Calm helps you find your peace. From guided meditations to sleep stories, this app is a haven for mental well-being.Key Features:Meditation sessions for beginners and experts.Sleep stories narrated by soothing voices.Breathing exercises to reduce anxiety.How to get started: Explore the free library of meditations and choose one that resonates with you. Dedicate a few minutes each day to mindfulness and relaxation.Final ThoughtsThese apps are more than just tools; they’re stepping stones to a better and more organized life. The best part? They’re completely free to use. Whether you’re looking to improve productivity, learn something new, or simply relax, these apps have got you covered. Start exploring them today and see how they can transform your daily routine!