Best Practices and Anti-Patterns in BDD Cucumber Automation - Part ll
Maintaining code in an organized and readable manner is crucial for efficient software development. One approach that proves highly effective in code maintenance is the Page Object Model (POM), which originated from Selenium WebDriver.
When you combine POM (Page Object Model) with your step definitions, it provides a well-organized and easy-to-maintain framework for automated testing.
This article explores the benefits of implementing POM with Cucumber and how it enhances code readability, reusability, and test execution efficiency.
The Page Object Model
The fundamental concept of the Page Object Model is to encapsulate the functionality and elements of a web page within dedicated page classes. These classes represent individual pages or specific sections of an application.
By utilizing page classes, test scenarios can interact with the application without directly referring to the browser or WebDriver instructions within step definitions.
This separation enhances code maintainability and readability, making it akin to a manual testing script at a higher level.
Creating Page Classes
Each page or functional area of the application is represented by a dedicated page class. For example, a "TenantedPage," "HeaderPage," or "ProjectsPage" class may be created.
Within these classes, methods are defined to perform specific actions on the respective pages. The methods within a page class utilize page elements that exist solely within that page class.
This clear separation ensures that methods and elements are tightly coupled, reducing code dependencies and promoting maintainability.
Advantages of Page Object Model
Readability: By leveraging the POM, step definitions become more readable and concise. The focus remains on the intended actions and interactions with the application, rather than low-level browser driver code. This readability aids in understanding test scenarios and facilitates collaboration between team members.
Reusability: The POM promotes the reuse of class and method calls from your step definitions. Since page classes encapsulate specific functionality, multiple scenarios can utilize the same methods within those classes. This reusability minimizes code duplication, improves efficiency, and simplifies code maintenance.
Code Maintenance: With the POM, code maintenance primarily occurs at the page class, method and/or element level. Changes or updates to a specific page can be made within its dedicated class, without affecting other parts of the codebase. This modularity makes maintenance tasks more manageable and reduces the risk of introducing unintended breaking changes.
Data-Driven Tests with Scenario Outlines
Cucumber offers a powerful feature called a scenario outline. This feature enables data-driven testing by utilizing examples. When using a scenario outline, each example can represent a unique test case with different input values.
This approach allows for extensive test coverage while keeping the scenarios concise and manageable. It is essential to strike a balance between the number of data rows and maintaining scenario readability.
Optimizing Test Execution with Hooks
Hooks in a Cucumber framework are invaluable for optimizing test execution. Hooks provide before all, before scenario, after scenario, and after all capabilities. The before hooks can be used to set up a clean starting state for each test or specific tests based on tags.
On the other hand, after hooks can be used for teardown and cleanup activities, ensuring environments remain clean and performance is optimized.
Best Practices for Hooks
Hooks are typically defined in a hooks file within the support directory of a Cucumber framework. Tags are used to associate specific hooks with relevant scenarios. For example, a before hook tagged with "apply_payment_method" can be called by scenarios requiring that functionality. Similarly, an after hook tagged with "delete_time_clocks" can perform cleanup tasks specific to scenarios involving time clocks.
BeforeAll and AfterAll hooks as the name suggests are utilized by every single scenario. These hooks are not associated with any specific tag and are called by all. BeforeAll and AfterAll hooks are extremely useful for setting up and tearing down the test environment. A BeforeAll hook might be used to process any associated framework test configuration and manage the browser opening for example.
They ensure that each test starts with a clean state and ends with proper cleanup, which helps maintain the integrity and reliability of the test suite and environment.
Avoid Nested Steps
It is crucial to avoid using nested steps or steps within steps. Although this feature was available in earlier versions of Cucumber, it has proven to be problematic for troubleshooting and maintaining test scripts. Nested steps hinder code readability and do not provide any tangible benefits to stakeholders.
Using Scenario Outlines and Example Tables
Scenario Outlines with data tables allow you to pass tabular data to your steps, which is particularly useful for testing scenarios with multiple data combinations. It helps in keeping your scenarios concise and avoids duplicating similar steps. This enables data-driven testing, where you can test the same scenario with different input values.
In the example provided, you can see the usage of a scenario outline with examples. The outline represents the core steps of the scenario, while the examples provide different combinations of values for the parameters.
It's important to use data tables and scenario outlines effectively. While they provide flexibility and reusability, it's crucial to strike a balance between the number of examples and the readability of the scenario. Too many examples or complex data tables can make the scenario hard to understand and maintain.
Parallel Testing
Lastly, let's discuss test execution runtime and the concept of running tests concurrently. Many automation frameworks, including Cucumber, support running tests in parallel to reduce the overall execution time.
When executing tests concurrently, it's important to balance the workload across the available threads or processes. In the case of Cucumber, the workload is typically divided at the feature level. The number of threads determines how many features each thread will handle.
To optimize test execution, you can aim for a balanced distribution of scenarios across features and a balanced use of scenario outlines with corresponding examples. This ensures that no single thread is overloaded with a large number of scenarios, resulting in more efficient test execution.
However, it's important to note that the workload balancing should not compromise the logical grouping of scenarios within features. The scenarios should still be organized based on the functionality they test and maintain their integrity.
Conclusion
Overall, these guidelines and best practices contribute to code maintainability, readability, and efficiency in Cucumber-based test automation frameworks.
By following these practices, you can ensure that your tests are robust, scalable, and easy to maintain and that the true intention of the BDD process in terms of generating conversation and collaboration between all vested stakeholders is maintained with integrity.
You can watch the complete guide to BDD + Cucumber Best Practices and Anti-Patterns Here: Video Guide