Here are the Cucumber BDD Interview Questions and Answers, based on my understanding. If you want my complete set of Cucumber BDD Questions and Answers as a document, you can message me on LinkedIn at Inder P Singh.
Answer: Cucumber is an open‑source tool that supports Behavior‑Driven Development, commonly called BDD. It allows teams to write test cases in plain English using a syntax called Gherkin. These tests, known as "scenarios" in Cucumber are easy to understand for both technical and non‑technical stakeholders. The goal of Cucumber is to help the communication between developers, testers, and business analysts by writing tests according to the business requirements. View an introduction to Cucumber.
Example: a basic Cucumber scenario may look like this:
Feature: User login Scenario: Successful login Given the user is on the login page When the user enters valid credentials Then the user is redirected to the dashboard- Improved Collaboration: Cucumber improves collaboration across teams by using a common language syntax (Gherkin) to describe tests. This allows business stakeholders, developers, and testers to all contribute to test scenarios, reducing misunderstanding.
- Early Testing: Cucumber works with Agile methodologies, where testing is done early and iteratively. Since the test scenarios are defined before development begins, it helps to build features according to the business requirements from the start.
- Living Documentation: Cucumber scenarios are also documentation. These readable test cases describe how the application should behave. They should be constantly updated with each sprint, so that they’re up‑to‑date with the system's functionality.
- Automation Support: Cucumber integrates with automation tools and frameworks like Selenium, allowing to automate acceptance tests. As the scenarios are in plain language, testers can link them to code, enabling continuous testing.
BDD stands for Behavior‑Driven Development. View What is BDD short video. BDD is an evolution of Test‑Driven Development (TDD) where tests are written in the form of expected behaviors of the application. Instead of focusing on technical tests, BDD focuses on the user’s perspective. Cucumber helps in implementing BDD because it provides a framework to write these behaviors as tests. The importance of BDD in Cucumber is its focus on collaboration, and guiding the features being developed to be according to the business needs. Cucumber’s structure encourages teams to think in terms of "what" the system should do, rather than "how" it should be built.
View Cucumber Interview Questions and Answers video in my Software and Testing Training channel or read on.
Answer: In Cucumber, these are the elements of how the tests are structured:
- Feature Files: Plain text files written using Gherkin syntax, where scenarios are described. Each feature file represents a specific functionality of the application, such as "User Login" or "Shopping Cart."
Example: A feature file might be as follows:
- Step Definitions: The code implementations of the steps defined in the Gherkin scenarios. Each Gherkin step (Given, When, Then) is linked to a corresponding code block in the step definition file.
Example: A Java step definition could look like:
- Gherkin Syntax: The language used to write feature files. It uses simple constructs like Given, When, Then, And, and But to describe system behavior in scenarios.
Answer: Writing clear and maintainable Gherkin scenarios is essential for successful Cucumber BDD. Some best practices include:
- Keep it Simple: Write steps in clear, concise language that non‑technical stakeholders can understand. Instead of “When the user clicks the button with id 'submitBtn'”, use “When the user submits the login form”.
- Single Behavior per Scenario: Each scenario should test only one specific behavior to keep maintenance easy.
- Avoid Technical Details: Scenarios should describe what the system does, not how it’s implemented.
- Use Background if needed: For repetitive setup steps (e.g., logging in), use a Background block. For example: - Readable Scenario Names: Give scenarios meaningful titles so their purpose is obvious at a glance.
Answer: Cucumber tags are used to organize and selectively run scenarios or entire feature files. Tags allow you to group scenarios based on their functionality, priority, or other criteria. Tags are added to the scenario or feature level using @ followed by a name. You can then specify which tags to run when executing tests. On a side note, you should subscribe to Software and Testing Training YouTube channel, if you’re interested in learning test automation effectively and quickly. The example of using tags is: You can run tests based on tags, such as only running @SmokeTest scenarios. For example, by using the command:
mvn test -Dcucumber.options="--tags @SmokeTest"
Answer: Cucumber tags provide:
- Selective Test Execution: Run suites by functionality or priority (e.g., smoke, regression).
- Parallel Execution: Enable parallel runs to reduce overall test time.
- Categorization: Make it easier to manage tests by feature, sprint, or other logical groups.
Answer: Integrating Cucumber with Java using Maven in test automation has the following steps:
Example:pom.xml dependencies:
- Set Up Your Feature Files and Step Definitions: Create a folder for your feature files and write your test scenarios using Gherkin syntax. Then, create step definition files that link the Gherkin steps to actual Java code.
Answer: A structured folder layout helps to maintain a Cucumber BDD project. Here's a suggested folder structure: - features: Contains all your Gherkin feature files. Each feature is a part of the application’s functionality.
Answer: The following are the important configuration files for running Cucumber tests:
Example: of a JUnit Runner class: This class gives Cucumber data on where the feature files are located and how to run them.
Answer: Integrating Cucumber with TestNG for test execution is commonly used in Java-based automation frameworks. The steps to do it are:
mvn test -Dsurefire.suiteXmlFiles=testng.xml
Answer: The testng.xml file and the runner class have roles in executing Cucumber tests within the TestNG framework. - testng.xml file: This configuration file tells TestNG how to organize and execute tests. It specifies which classes to run, allows for grouping, and supports parallel execution of tests. You can also define test suites and control the order of execution, which is useful for managing large test sets. - Runner Class: The runner class launches the Cucumber tests. For TestNG, the runner class extends AbstractTestNGCucumberTests, which integrates Cucumber with TestNG. In this class, you define the location of the feature files, step definitions, and any other Cucumber options like reporting plugins.
Answer: Running Cucumber tests in parallel using TestNG can reduce total execution time, especially when there are many scenarios to test. The steps to set it up are below. If you need code snippets, you can connect to me at https://www.linkedin.com/in/inderpsingh/ - Enable Parallel Execution in testng.xml: TestNG allows you to run tests in parallel by adding a parallel attribute in the suite tag of your testng.xml file. The example configuration for parallel execution is: - Run Scenarios in Parallel: To run individual Cucumber scenarios in parallel, you need to configure your runner class to enable parallel execution. This can be done by overriding the scenarios() method in the runner class. The example of enabling parallel execution in the runner class is below. In this setup, each Cucumber scenario will run in parallel, using the parallel = true attribute in the @DataProvider annotation. - Run the Tests: You can then execute the tests using Maven (see example below) or from your IDE. TestNG will run the tests in parallel across multiple threads as defined.
mvn test -Dsurefire.suiteXmlFiles=testng.xml
Answer: Setting up Cucumber with JUnit for running BDD tests is common in Java-based automation frameworks. The steps to get it working:
Answer: TestNG and JUnit frameworks used to execute Cucumber tests have some differences in terms of features and flexibility:
Difference | JUnit | TestNG |
---|---|---|
Annotations | Uses simple annotations like @Before, @After, and @Test. | Has more advanced annotations like @BeforeClass, @AfterClass, @BeforeSuite, and @AfterSuite, which allow for more levels of control over test execution. |
Test Configuration | No built-in configuration file; all configuration is done in code, typically in the runner class or via custom setups. | Uses testng.xml for advanced configuration, which can be used to define test suites, groups, and enable parallel execution. |
Parallel Execution | Running tests in parallel requires extra setup or third-party plugins like Maven Surefire. JUnit 4 doesn’t have built-in support for parallel execution. | Has built-in support for parallel execution with a simple configuration in the testng.xml file. |
Flexibility | Lightweight and suitable for simple test cases but lacks the advanced features of TestNG. | More powerful in terms of grouping tests, running them in parallel, and generating advanced reports. |
Dependency Injection | Supports dependency injection with frameworks like Spring, but configuration can be more complex. | Built-in dependency injection, making it more flexible for test setups requiring external dependencies. |
Answer: To integrate Rest Assured with Cucumber for API testing, follow these steps:
Example:
- Write Step Definitions: The step definitions use Rest Assured to handle API requests and responses. You should implement the logic here for the steps defined in the feature file.
Example:
- Run the Tests: Finally, you run the tests via your Cucumber runner class or with Maven. The Cucumber runner class executes the feature file and maps the steps to the Rest Assured API interactions.
Example:
Answer: Writing API scenarios in Gherkin for Cucumber makes them human-readable. Here’s how you can write API scenarios:
Example:
Feature: API testing for User details endpoint
Example:
Scenario: Verify API response for user details
- Write Gherkin Steps: Use Given, When, and Then steps to define the conditions, actions, and expected outcomes of the API call.
- Given sets up the initial context, such as the API endpoint.
- When describes the action, such as sending a request.
- Then checks the expected result, such as the status code or response content.
Example:
Given I set the API endpoint to "/users/1" When I send a GET request Then the response status should be 200 And the JSON response field "name" should equal "John Doe"
Answer: Managing JSON responses and API requests in Cucumber BDD is done using the step definitions where you interact with the APIs using Rest Assured. Here’s how you can handle API requests and JSON responses:
Response response = given().when().get(apiEndpoint);For a POST request with a JSON payload:
- Extracting Data from JSON Responses: Rest Assured has the feature to parse JSON responses. You can extract values from the response body using methods like jsonPath().
Example:
String userName = response.jsonPath().getString("name");- Assertions on JSON Responses: Once you’ve extracted the necessary data from the JSON response, you can assert that it matches the expected result.
Example:
Assert.assertEquals("John Doe", userName);- Handling Complex JSON: If the API returns a complex JSON response with nested objects, you can use jsonPath to navigate the structure.
Example:
String city = response.jsonPath().getString("address.city");
Answer: Data-driven testing in Cucumber is achieved using the Scenario Outline and Examples keywords. Scenario Outline allows you to write a single scenario and run it multiple times with different sets of test data. The Examples keyword is used to define the data. In the example below, the same steps are executed for each row of data in the Examples table. Cucumber will replace the placeholders (username, password, message) with the corresponding values from each row during execution.
Answer: Hooks in Cucumber allow you to run blocks of code before or after each scenario. They set up preconditions and clean up after test execution. These hooks are useful where you need to initialize resources like databases or browsers before the tests run and release resources or reset states afterward. There are two main types of hooks:
- @Before: This hook runs before each scenario.
- @After: This hook runs after each scenario.
Example:
Answer: In Cucumber, the term glue refers to the code that connects the Gherkin steps in feature files to their corresponding step definitions in Java (or any other language that Cucumber supports). The glue option in the Cucumber runner class defines the package where the step definition files are located. For example, if your step definitions are in the stepDefinitions package, you would specify the glue path in the runner class like below. The glue links the feature steps to the step definition methods that contain the logic for each step. Without the correct glue path, Cucumber will not know where to find the step definitions, and the tests will fail to execute properly.