Quality Gates - General Types and Areas of Coverage

In the previous article we started with an introduction to software testing. In this article we will go into more detail, and start with Quality Gates. I will try to describe their basic types and coverage areas in software testing.

Quality Gates are key checkpoints in the software development lifecycle. We need to make sure that software meets requirements and quality criteria. Only if the criteria is met, can we proceed to the next stage. Quality Gates act as a barrier against problems proliferating through the testing process, thus preventing them from impacting the final product.

Quality Gate Types

There are many different types of testing, each designed to address specific aspects of the software. We will only focus on a few of the common ones:

1. Smoke testing: Smoke tests are a quick and superficial check. They serve to check that the core functionalities are working and that the system is stable enough for more in-depth testing. Smoke tests are designed to "smoke out" any major issues that may prevent further testing. A successful smoke test indicates that the software is ready for further validation.
2. Functional testing: This type of testing validates that the software functions  as specified in the requirements. It focuses on verifying that each feature performs correctly. Functional tests are often based on user stories and use cases. Examples include testing login functionality, shopping cart processes, data input validation, or so on.
3. Regression testing: When we add new code there is a chance that we have broken existing functionality. During regression we re-execute test cases to ensure that the changes have not introduced defects into previously working functionality. Essentially, it is a "baseline" of previous tests to ensure that previously tested features continue to work as expected. Regression testing is critical to maintaining stability and preventing new problems from being introduced. It covers a wide range of software areas, including major and minor features, to ensure that the software remains stable and reliable.
4. Other types: In addition to the above, there are also many other types of testing like:

• Acceptance testing: Validating that the software meets the customer's expectations and is ready for release.
• Usability testing: Assessing the user-friendliness and intuitiveness of the application.
• Sanity testing: Checking that recent changes or issue fixes haven't broken existing particular functionality.
• Performance testing: Evaluating the responsiveness, stability, and scalability of the application under various load conditions.
• Security testing: Identifying vulnerabilities and ensuring the software is protected against unauthorized access and security threats.

Quality Gates Functional Areas

Testing functional areas refer to the specific aspects of the software. These areas help to organize and categorize efforts, ensuring comprehensive coverage and minimizing the risk of overlooking critical functionalities. Here are some common functional areas:

1. Front-end testing: This focuses on the user interface (UI) and user experience (UX). It verifies that visual elements are displayed correctly, navigation is intuitive, and the application is responsive across different devices. Front-end testing often involves UI automation tools and cross-browser compatibility testing.
2. Process testing: This area checks the workflows and business processes implemented within the application. It ensures that data flows correctly between different modules and that business rules are enforced. Process testing often involves complex scenarios and integration testing.
3. Back-end testing: This focuses on the server-side (aka “back-side”) components of the software, including the database, APIs, and business logic. Back-end testing verifies data integrity, database performance, and the correct functioning of APIs. It often involves database queries, API testing tools, and performance testing.

During testing it is important to understand that different testing types and functional areas sometimes overlap. Often we cannot perform one type of testing without successfully completing the other. They can be interrelated and dependent on each other. 

For instance, a functional test might cover both front-end and back-end components. It verifies that a user can submit a form (front-end) and that the data is correctly stored in the database (back-end). Regression testing is applied across all functional areas to ensure that changes haven't introduced issues anywhere in the application.

The testing team helps to determine the optimal combination of testing strategies and approaches based on efficiency, speed and quality. This is a key factor in achieving reasonable testing and software development deadlines. It is necessary to carefully analyze the risks and priorities of the application in order to select the most appropriate types of testing. By combining different methodologies, it is possible to ensure comprehensive coverage and proper quality, while efficiently using the time spent on development.