If you want to get started with API (application programming interface) testing and learn about the different testing types and steps to perform to make the process more efficient, you have landed on the right post.
When it comes to ensuring API quality, there is a need to form a solid QA strategy. It is quite simpler, and APIs don’t need a different approach for application. The most important thing to have is thorough technical knowledge – everything from the client-server architecture to the principles of HTTP protocols, XML, JSON, and other data formats.
To help you learn more about API testing, we have covered its major benefits and types, in addition to discussing a three-step approach to develop a solid QA strategy for delivering high-quality IT products to the market.
Benefits of Testing APIs
It has now become important to ensure that IT solutions coexist without failures since an increasing number of them rely on microservice architecture. According to Verified Market Research, the global API testing industry is expected to reach $2,550 million by 2027. The reason for this dramatic increase in the market would be the abundance of benefits API testing provide to businesses. Following are the major benefits of API testing, which help companies deliver great IT solutions to the industry.
- Better Test Coverage – Enhanced test coverage is the biggest benefit of API test automation. It covers a substantial amount of test cases targeted toward finding and solving critical issues.
- Improved Time to Market (TTM) – It helps with early bug identification, which saves time between development and testing cycles and leads to quicker product delivery to the market.
- Fewer Risks – With API testing, companies can check the business logic early, i.e., at the start of the Software Development Life Cycle (SDLC), and work immediately on the reported issues, which helps them reduce the risks as a result.
- Streamlined Test Maintenance – The API tests are simplified and efficient; thereby, changes only occur when there are changes made to the software business logic. This, as a result, makes the test maintenance quite easy and decreases the overall testing duration.
- Greater Access to Apps without UI – API testing can even work without UI, which helps with getting rid of issues before any effect on GUI and avoiding serious problems that are difficult to fix afterward.
- Increased Security – API testing needs strong inputs and an environment that helps secure the application and prevent cyber penetration. According to Gartner’s predictions, in companies with not enough security measures, API may become the most common attack point in 2022.
Types of API Testing
Bearing in mind that an application’s API later is one of the major components, it is responsible for the client-server interaction, as well as manages the business operations and delivers desired services to the customers. If the API does not operate as intended, it can put the complete chain of business functions on line.
As an important unit of the service layer, according to Mike Cohn’s test pyramid, it is important for the API layer to include nearly 20% of the tests performed to ensure increased software reliability. Here are some tests to include when testing APIs:
Performance Testing
Performance testing is a testing practice that evaluates how an IT solution performs in terms of stability under a particular workload. These tests are usually executed to examine the speed, response time, stability, and reliability of a system and to help prevent failures caused due to an increase in end users.
Security Testing
Organizations experience more and more threats with an increase in cybersecurity issues, according to the Mobile Security Index Report. In 2020, around 39% of companies greatly encountered security issues, including IoT/mobile devices.
API testing is useful to ensure an advanced level of security from external attacks. These tests uncover and eliminate vulnerabilities of a system and protect the data and resources from possible intruders.
Requirement Testing
This type of testing helps put an end to software inconsistencies and targets identifying and fixing bugs before the development phase.
Backward Compatibility Testing
Backward compatibility testing is useful in examining the response and compatibility of the developed solution with their older API versions for streamlined operations.
Code-level Testing
Code-level testing is a testing practice that helps verify the source code and its performance under varied inputs (minimum/maximum limit, valid/invalid, false testing data) and conditions.
Interface Testing
Checking the usability of the user interface (UI) related to API is vital. So, interface testing is conducted to test the accessibility and ability of the application (both front- and back-end) and ensure that UI functions work as intended.
Validation Testing
In most cases, validation testing is performed during the development phase, right after the verification of the API components. Validation tests focus on examining the performance and effectiveness of a solution to ensure the IT product is fully functional and works as per the stated requirements.
These are the seven basic and important types of API testing. Other types, like integration, end-to-end, etc., are also performed at times, depending on the specific business requirements.
How to Get Started with API Testing
Now that you are familiar with the benefits and testing types to perform on API, it is time to learn how to get started with API testing. Besides having a team of quality assurance professionals with extensive API expertise, you need to perform the following basic steps to create a robust API testing strategy:
1. Build an Environment and Configure Parameters
Database configuration and server input and output parameters definition are helpful in setting up the proper environment for API testing. For more accurate results, it is always a better approach to simulate the real-time conditions important for the software’s public use. This helps with application verification while fixing critical issues that slow down the right performance.
2. Form a Test Plan
This step involves defining what types of testing should be performed to increase software quality and put an end to all defects. Different scenarios, such as positive tests, help in checking the basic functionality of an IT solution. Negative tests are useful in checking the system’s ability to handle problems related to performance and security.
3. Choose API Testing Tools
The tool type has a significant impact on the success of an IT solution and the accuracy of the obtained results. Selecting the right tools for API testing helps companies reach greater testing process efficiency. Different testing tools are available in the market. Some of the best API testing tools include Postman, Apache JMeter, SoapUI, Apache HTTP, Swagger, REST-assured, and Requests. These tools support API architecture, have improved reporting capabilities, and adjust to multiple testing types like performance and security testing.
The above-mentioned steps greatly help companies in successfully delivering top-quality IT solutions to the industry that meets end users’ requirements.
Final Words
Having a robust QA strategy in place is vital for API testing to achieve operational and business benefits like delivering quality products. While performing API testing, companies need to focus on the critical aspects of an application, i.e., performance, security, requirements, compatibility, code, interface, and validation. We have shared our three-step strategy to help companies overcome the existing challenges and find serious issues to ensure a stable system.
