Mindmap to Understand Selenium 4 architecture

 Selenium is one of the most popular open-source automation testing tools, widely used for web application testing. It is important to know its architecture — the flow of communication between test script, Selenium components, and the browser.

Selenium 4 Architecture

Components of Selenium Architecture

Selenium Client Libraries (Language Bindings)

These are language-specific libraries provided by Selenium. Test scripts use these libraries to interact with the browser using high-level commands. The client libraries translate these high-level commands into W3C WebDriver Protocol requests.

Browser Drivers

Each browser requires a dedicated driver to interpret Selenium commands. Browser drivers act as a bridge between your Selenium script and the actual browser. They receive HTTP commands (W3C Protocol) from Selenium, convert them into native browser actions, and send back responses to Selenium.

Browsers

Real browsers (Chrome, etc.) that open the web page and execute actual user interactions. The browser responds to commands (click, type, navigate) and sends the results back through the browser driver.

Selenium 4 – End-to-End Flow

W3C WebDriver Protocol in Selenium 4

• Starting from Selenium 4, Selenium uses the W3C WebDriver Protocol by default.
• This is a standard communication protocol defined by the World Wide Web Consortium (W3C).

It ensures:

• Consistent behavior across all browsers.
• Direct communication between Selenium and modern browsers.
• No dependency on legacy JSON Wire Protocol.

Selenium Libraries:

Selenium Libraries are the backbone of Selenium automation, providing a simple and language-friendly API to control browsers via the W3C WebDriver Protocol.

Selenium Capabilities and Libraries

Useful Documentation

https://www.selenium.dev/documentation/

https://w3c.github.io/webdriver/

https://www.selenium.dev/blog/

https://github.com/SeleniumHQ/selenium

https://www.toolsqa.com/selenium-webdriver/selenium-4/

https://www.youtube.com/@seleniumhq

Automation Testing - Top interview question

In this post , we will be discussing answers to questions asked in interviews for automation

What is Automation Testing?

Automation testing is a software testing technique that uses automated tools and scripts to perform tests on software applications. The primary goal of automation testing is to increase the efficiency, effectiveness, and coverage of the testing process. This approach is especially beneficial for repetitive and regression testing tasks.

What is difference between automation and manual testing?

Automated testing uses scripts and tools to perform tests, whereas manual testing requires human intervention to execute tests. Automated testing is faster and more reliable for repetitive tasks, while manual testing is better for exploratory, usability, and ad-hoc testing

What are key features of automation?

What are different Types of tests that are automated?

Unit Tests

• Validates: individual components or units of code.
• Tools : junit, TestNG and microtests

Integration Tests

• Validates: interaction between integrated units or components
• Tools: junit, TestNG and microtests

Functional Tests

• Validates: application functions as the specified requirements. Includes both UI and API workflows.
• Tools: Selenium, Playwright, Rest Assured, Cucumber

Performance Tests

• Validates: application's performance under various conditions. Includes load testing, stress testing.
• Tools: Jmeter, LoadRunner, Locust

What are best suited tasks for automation?

Repetitive, time-consuming tasks, regression tests, smoke tests, performance tests, data-driven tests, and tasks that require precision and consistency are well-suited for automation.

What are most used automation tools and frameworks?

Popular tools and frameworks include Selenium, JUnit, TestNG, Cypress, Appium, Jenkins, Cucumber, Playwright and Robot Framework.

What is a test automation framework?

Definition: A structured set of guidelines and best practices designed to help testers and developers automate the testing of software applications. 

Key Components and Characteristics: 

• Code Reusability: Encourages the reuse of code, reducing duplication and maintenance efforts. 
• Scalability: Supports scaling of test scripts to handle larger and more complex applications.
• Modularity: Test scripts and components are organized in a modular fashion for easier management. 
• Maintainability: Provides clear guidelines and structure for easier maintenance and updates. 
• Test Data Management: Offers mechanisms to handle test data efficiently. 
• Reporting: Includes reporting tools for detailed test execution results and logs. 
• Integration: Can integrate with various tools and systems (e.g., CI/CD, version control). 
• Best Practices: Promotes best practices in coding, such as design patterns and naming conventions. 

Types of Automation Frameworks: 

• Linear Scripting Framework: Record-and-playback approach.
• Modular Testing Framework: Breaks down application into smaller, independent modules. 
• Data-Driven Framework: Separates test scripts from test data. 
• Keyword-Driven Framework: Uses keywords to represent actions for readability and maintenance. 
• Hybrid Framework: Combines features of multiple frameworks. 
• Behavior-Driven Development (BDD) Framework: Uses natural language constructs for test cases.

What are the merits and demerits of using Selenium for automation?

Merits of Selenium:

• Open Source: Selenium is free to use, which makes it a cost-effective option for businesses of all sizes.

• Language Support: Supports multiple programming languages.

• Browser Compatibility: Works with all major browsers ensuring broad compatibility.

• Platform Independence: Can run on various operating systems 

• Framework Integration: Easily integrates with other tools and frameworks like TestNG, JUnit, Maven, Jenkins, and Docker, facilitating continuous integration and continuous deployment (CI/CD).

• Community Support: Has a large and active community, providing extensive resources.

• Flexibility: Offers flexibility in designing tests, such as using a wide range of locators for identifying web elements.

Demerits of Selenium:

• Limited to Web Applications: doesn't support desktop or mobile application testing natively.

• Steep Learning Curve: Requires knowledge of programming languages and frameworks

• Maintenance Overhead: Tests can become fragile and require updates with UI changes.

• No Built-in Reporting: use of third-party tools for generating test reports.

• Complexity with Dynamic Elements: Handling dynamic web elements (such as AJAX-based elements) can be complex and may require additional coding.

• Browser-Specific Issues: Tests might behave differently across different browsers.

• Performance: Can be slower compared to other automation tools like playwright

How does a (CI/CD) pipeline integrate with automation testing?

CI/CD pipelines automatically run tests every time code is committed, ensuring new changes don't break existing functionality. They integrate with automation tools to execute tests, report results.

How do you handle dynamic elements in web automation?

We can handle dynamic elements using dynamic XPath/CSS selectors, waiting mechanisms (explicit, implicit, and fluent waits), and interacting with elements based on properties like text, class, or other attributes.

What is the difference between functional and non-functional automation?

Functional testing checks if the application functions according to requirements. Non-functional testing evaluates aspects like performance, usability, and security.

What is the Page Object Model (POM)?

The Page Object Model (POM) is a design pattern in Selenium that enhances test maintenance and reduces code duplication by encapsulating web elements and their interactions in separate classes.

What is data-driven testing?

Data-driven testing is a methodology in which test data is stored separately from test scripts, allowing tests to be run multiple times with different sets of data.

What is a headless browser?

A headless browser is a web browser without a graphical user interface (GUI). It is used for faster, resource-efficient testing where GUI interaction is not necessary.

How do you handle an element with locator dynamically changing?

Here are a few approaches to manage dynamically changing locators:

• Relative locators can help you find elements based on their position relative to other stable elements.
• XPath axes allow you to navigate to elements based on their relationships to other elements.
• Use CSS selectors to navigate through the DOM based on the hierarchy of elements
• Some locators allow the use of regular expressions to match dynamic parts of the locator.
• Use of java script executor

What are  ‘flaky tests’?

Flaky tests are tests that produce inconsistent results, sometimes passing and sometimes failing without any changes in the codebase. They can be caused by timing issues, environmental dependencies, or unreliable locators. 

To fix flaky tests:

• Add appropriate waits to handle timing issues.
• Ensure test environments are stable and consistent.
• Use more reliable locators and checking for element visibility or readiness.
• Creating independent test to ensure no impact of a test on other
• Running tests multiple times to identify and address flaky behavior.

BDD with cucumber and gherkins using MindMap

 Business-Driven Development is a collaborative approach that focuses on aligning software development with business goals through the creation of executable specifications

Business driven development

Translating Business-Driven Development to executable specification in gherkins

Keywords and code blocks in Gherkins specification

• Feature is to provide a high-level description of a software feature.
• Rule is to represent one business rule that should be implemented
• Scenario or Example is a concrete example that illustrates a business rule
• Scenario Outline is used to run the same Scenario multiple times, with different set of data.

• Steps are used to define scenarios. steps can be:
• Given - describe the precondition of the system
• When - describes an event, or an action
• Then - describe an expected outcome, or result
• But - describe an outcome that is not expected
• There can be multiple steps of same type in a scenario.
• Background define a set of steps that are common to all scenarios in a feature file. Execution is after each scenarios
• Hooks are blocks of code that run before or after certain events. they are defined by annotation "@Before" and "@After" annotations. these are setup() and teardown() code in the application.

Understanding components of a cucumber framework

Components of a cucumber framework

Feature File:

• File corresponding to a feature/rule
• Can have multiple scenarios/examples, scenario outline and background.
• Annotations can be used to group tests, e.g: smoke, nightly, regression

Step definition File

• For given, when then, but steps defined in feature file, the logical code is written in a step definition file.
• Annotation @Given, @then are used to match the step definition method with the one provided in feature file

TestRunner File to execute tests

• TestRunner file defines the tests to be executed,

Components of a Test Runner File:

• Annotations: uses annotations from testing frameworks like JUnit or TestNG to define its purpose and behavior.
• Glue: specifies the package where Cucumber can find the step definitions
• Features: feature files which needs to be executed
• Plugins: defines the reporting path, tags and formatting.

References :

https://www.linkedin.com/learning/cucumber-essential-training

https://cucumber.io/docs/gherkin/reference/