Automation Interview Questions

📖 Q1

What is Playwright?

Simple Answer: Playwright is a modern test automation tool made by Microsoft. It helps you test websites automatically in different browsers like Chrome, Firefox, and Safari.

Think of it like a robot that opens a browser, clicks buttons, fills forms, and checks if everything works correctly – just like a human tester, but faster and more accurate.

🔑 Key Points

Made by Microsoft – Developed and maintained by Microsoft
Works on all major browsers – Chrome, Firefox, Safari
One code for all browsers – Write once, test everywhere
Auto-waiting – Automatically waits for elements to be ready
Reliable tests – Tests don't break due to timing issues
Multiple languages – Works with JavaScript, Python, .NET, and Java

💻 Example: Simple Google Search Test

const { test, expect } = require('@playwright/test');

test('Search Google for Playwright', async ({ page }) => {
  await page.goto('https://www.google.com');
  await page.fill('input[name="q"]', 'Playwright');
  await page.press('input[name="q"]', 'Enter');
  await page.waitForSelector('h3');

  const firstResult = await page.textContent('h3');
  expect(firstResult).toContain('Playwright');

  await page.screenshot({ path: 'google-search.png' });
});

What this code does — Step by Step

Opens the Google homepage
Types "Playwright" into the search box
Presses Enter to search
Waits for the search results to load
Checks if the first result contains "Playwright"
Takes a screenshot of the results page

Try It Yourself

Change the search text from "Playwright" to "Automation Testing". Then change the assertion to check if the first result contains "Automation".

⚡ Q2

What are the Key Features of Playwright?

Simple Answer: Playwright has many useful features that make testing easier. Here are the most important ones explained simply:

🎯 Features

⏳ Auto-Waiting

Playwright waits automatically for elements to appear. You don't need to add manual waits.

🌐 Cross-Browser

Same test code works on Chrome, Firefox, and Safari. No browser-specific code needed.

🚀 Parallel Execution

Run many tests at the same time to save time. Great for large test suites.

📸 Tracing & Screenshots

Automatically captures screenshots and videos when tests fail. Helps debug quickly.

🎯 Smart Selectors

Find elements using text, role, test-id, and more. More reliable than old methods.

🌐 Network Control

Mock API responses and intercept network requests. Test edge cases easily.

📱 Device Emulation

Test mobile views by emulating devices like iPhone, iPad, and Pixel.

📊 HTML Reports

Generates detailed HTML reports with screenshots and test execution details.

💻 Examples

1. Auto-Waiting

test('Auto-waiting example', async ({ page }) => {
  await page.goto('https://example.com');
  await page.click('button#submit');
  await page.fill('input#name', 'John');
  await expect(page.locator('.success-message')).toBeVisible();
});

Step by Step

Opens the page
Waits automatically until the submit button is clickable, then clicks it
Waits automatically until the input is visible, then fills it
Waits until the success message appears before checking it — no sleep() needed

2. Running on All Browsers

module.exports = {
  projects: [
    { name: 'chromium' },
    { name: 'firefox' },
    { name: 'webkit' },
  ]
};

test('Works on all browsers', async ({ page }) => {
  await page.goto('https://example.com');
  await expect(page).toHaveTitle('Example Domain');
});

Step by Step

Register three browser projects once — Chromium (Chrome), Firefox, and WebKit (Safari)
Write the test only once
Playwright automatically runs the same test on all three browsers

3. Smart Selectors

await page.locator('button.submit-btn').click();
await page.locator('text=Login').click();
await page.locator('role=button', { name: 'Submit' }).click();
await page.locator('[data-testid="login-btn"]').click();
await page.locator('placeholder=Enter name').fill('John');

Step by Step

Find and click a button using its CSS class
Find and click an element using its visible text
Find and click a button using its accessibility role — best for accessibility
Find and click an element using its test-id — most stable option
Find an input using its placeholder text and fill it

4. Screenshots

test('Take screenshots', async ({ page }) => {
  await page.goto('https://example.com');
  await page.screenshot({ path: 'fullpage.png', fullPage: true });
  await page.locator('header').screenshot({ path: 'header.png' });
});

Step by Step

Opens the page
Takes a screenshot of the full page and saves it
Takes a screenshot of just the header element and saves it

5. Mock API Responses

test('Mock API response', async ({ page }) => {
  await page.route('**/api/users', route => {
    route.fulfill({
      status: 200,
      body: JSON.stringify([
        { id: 1, name: 'John' },
        { id: 2, name: 'Jane' }
      ])
    });
  });

  await page.goto('https://example.com');
});

Step by Step

Intercepts any call made to the /api/users endpoint
Fulfills that call with a fake (mocked) JSON response instead of hitting the real API
Opens the page — it will show the mocked data

📊 Playwright vs Selenium

Feature	Playwright	Selenium
Auto-Waiting	✅ Built-in	❌ Manual waits needed
WebDriver	✅ Not needed	❌ Requires WebDriver
Cross-Browser	✅ Chrome, Firefox, Safari	✅ Chrome, Firefox, Safari, Edge
Built-in Tracing	✅ Yes	❌ No
Network Control	✅ Built-in	❌ Limited

Practice Exercise

Create a test that: 1) Opens a website, 2) Takes a screenshot, 3) Mocks an API response, 4) Verifies the mocked data appears on the page.

💡 Summary

Playwright is a modern, powerful testing tool with many built-in features that make test automation faster, more reliable, and easier to debug.

🔧 Selenium

What is Selenium?

Simple Answer: Selenium is a free, open-source tool used to automate web browsers. It lets you write code that opens a browser, clicks links, fills forms, and checks results — just like a real user, but automatically.

It's one of the oldest and most widely used automation tools in the QA industry, supported by almost every company that does web testing.

🔑 Key Points

Open-source – Free to use, backed by a large community
Cross-browser – Works with Chrome, Firefox, Edge, and Safari
Multiple languages – Supports Java, Python, C#, JavaScript, and Ruby
WebDriver based – Talks directly to the browser using the WebDriver protocol
Framework friendly – Works well with TestNG, JUnit, and Maven
Huge industry adoption – Most in-demand skill in QA automation job postings

💻 Example: Simple Login Test (Java)

WebDriver driver = new ChromeDriver();
driver.get("https://example.com/login");

driver.findElement(By.id("username")).sendKeys("testuser");
driver.findElement(By.id("password")).sendKeys("password123");
driver.findElement(By.id("loginBtn")).click();

String welcomeText = driver.findElement(By.id("welcomeMsg")).getText();
Assert.assertEquals(welcomeText, "Welcome, testuser!");

driver.quit();

Step by Step

Opens Chrome using WebDriver and navigates to the login page
Enters the username and password into the input fields
Clicks the login button
Reads the welcome message shown after login
Verifies the welcome message matches what is expected
Closes the browser

Try It Yourself

Change the assertion to check that the URL after login contains "/dashboard" instead of checking the welcome text.

📱 Appium

What is Appium?

Simple Answer: Appium is a free, open-source tool used to automate mobile apps — both Android and iOS. It works for native apps, hybrid apps, and mobile web, without needing to change the app's code.

Think of it as Selenium for mobile — the same idea of automating user actions, but applied to phones and tablets instead of a desktop browser.

🔑 Key Points

Cross-platform – Works for both Android and iOS with a similar API
No app code changes needed – Automates the app exactly as it is
Multiple languages – Supports Java, Python, JavaScript, and more
Native, hybrid & web apps – Handles all major mobile app types
Real devices & emulators – Can run tests on real phones, simulators, or cloud devices
Built on WebDriver protocol – Similar architecture and commands to Selenium

💻 Example: Simple Login Test (Java)

DesiredCapabilities caps = new DesiredCapabilities();
caps.setCapability("platformName", "Android");
caps.setCapability("deviceName", "Pixel_5");
caps.setCapability("appPackage", "com.example.app");
caps.setCapability("appActivity", ".LoginActivity");

AndroidDriver driver = new AndroidDriver(new URL("http://localhost:4723/wd/hub"), caps);

driver.findElement(By.id("com.example.app:id/username")).sendKeys("testuser");
driver.findElement(By.id("com.example.app:id/password")).sendKeys("password123");
driver.findElement(By.id("com.example.app:id/loginBtn")).click();

String welcomeText = driver.findElement(By.id("com.example.app:id/welcomeMsg")).getText();
Assert.assertEquals(welcomeText, "Welcome, testuser!");

driver.quit();

Step by Step

Sets up device and app details (platform, device name, app package, launch activity)
Connects to the Appium server and launches the app on the device
Enters username and password into the app's login fields
Taps the login button
Reads the welcome message shown after login
Verifies the welcome message matches what is expected, then closes the session

Try It Yourself

Change the capabilities to target iOS instead of Android — swap platformName to "iOS" and update the device/app details accordingly.

🌐 API Testing

What is API Testing?

Simple Answer: API Testing means checking whether the backend of an application — the part that sends and receives data — works correctly, without touching the actual user interface (UI).

Instead of clicking buttons on a screen, you directly send requests (like GET, POST, PUT, DELETE) to the server and check if the response is correct — the data, the status code, and the response time.

🔑 Key Points

Faster than UI testing – No browser or app rendering involved
Tests the logic layer – Validates business logic directly at the source
Common tools – Postman, REST Assured, and RestSharp
Key checks – Status code, response body, headers, and response time
Works early in development – Can be tested before the UI is even built
Great for automation – Very stable, rarely breaks due to UI changes

💻 Example: Simple GET Request Test (REST Assured)

given()
  .baseUri("https://api.example.com")
.when()
  .get("/users/1")
.then()
  .statusCode(200)
  .body("name", equalTo("John Doe"))
  .body("email", equalTo("john@example.com"))
  .time(lessThan(2000L));

Step by Step

Sets the base URL of the API
Sends a GET request to the /users/1 endpoint
Checks that the response status code is 200 (success)
Verifies the "name" and "email" fields in the response body
Checks that the response arrived within 2 seconds

Try It Yourself

Write a POST request test that creates a new user and verifies the response status code is 201 (Created).