Testing is one of the most important stages in the development of any software or product, and it has been used for years to provide superior results. However, each product may require a different kind of testing. For instance, even though functionality testing is sufficient for a website, security testing is still necessary. With significant advancements in SDLC methodologies, we now have a variety of testing methods that ensure the highest quality goods via all endpoints, with API testing being one of them. 

The testing phase is crucial for a number of reasons, including security, quality, cost-effectiveness, customer satisfaction, performance understanding, hitting a wall with an unknown feature, and how testing improves the entire development process.  

Application Programming Interface, or API, is an interface that facilitates communication between two software systems. It is possible to link certain functionality or business operations with front-end code to abstract the written business logic and programming complexity, and this is known as a function. The separation of business logic from other application resources and cross-platform compatibility would both be greatly aided by API. 

 1. API Testing 

An approach to testing that regulates the specifications for various software operations and incorporates the point testing of Application Programming Interfaces Here, instead of using user input, a series of calls is made to the API, which is then queried for a response. To put it simply, API is a set of programming tools and commands that programmers can use to develop code at different levels. Every time we conduct a basic product search on Amazon, we employ developer-written APIs.  

2. Advantages of API Testing  

The following list includes the main benefits of API software testing. 

2.1 Assists in identifying minor concerns before they develop into larger ones. 

Prior to GUI tests, API testing allows one to assess the strength of the apps and evaluate code-level functionality. It can assist in finding minor mistakes early on before they grow into bigger problems later. Core access supports testing in addition to testing, improves communication, and promotes teamwork. It is particularly useful when dealing with overseas QA teams. 

2.2 Time Efficient 

Comparatively speaking, API testing takes less time than functional GUI testing. The fact that GUI testing necessitates pulling web page elements is one of the main factors contributing to its time-consuming nature. On the other hand, API testing can significantly reduce the time needed for GUI testing. For instance, it takes about 9 hours to complete 30,000 automated API tests. When employing parallel execution, the same amount of GUI tests take around 50 hours. When opposed to GUI tests, API testing requires less code, which allows for better and faster test coverage. Reduced testing costs are another benefit of API testing. 

2.3 Easier GUI integration 

Testing for greater integration is made feasible through API testing (more so if you are planning to conduct GUI testing at a later stage). For instance, tasks like adding new users to an application before running GUI tests become simpler and faster. 

 2.4 Language-Independent 

When testing APIs, the transfer model is agnostic of language. JSON or XML are used to exchange the data. When automating the testing of the apps, you can choose any core language. 

 3. How is API testing done?  

There are several tests that pertain to APIs, and testing these areas ensures API functionality. On the basis of API testing, the majority of the software is covered by tests for functionality, reliability, load, security, proficiency, etc. Negative testing is one of the most intriguing tests because it involves predicting what can go wrong, setting up a test, and making sure that even if it does go wrong as expected, it won’t affect the functionality of the entire system. 

3.1 Environment 

Setting up the testing environment can be difficult because there is no GUI involved and all you do is fiddle with the parameters. access the database and call APIs. 

3.2 Test Cases 

Several test cases are prepared, including what the return value would be, what happens if the answer is null or absent, what happens if another API is called, whether or not it is significant, etc. 

 3.3 Output 

 Different outputs will be anticipated for various test cases, and it’s crucial to contrast the actual output with what was anticipated later. 

 4. Why are APIs crucial and needed?  

As was already noted, API might be thought of as an application engine and should be anticipated to operate without any glitches or failures. We must perform testing operations on the set of APIs in order to accomplish this. In addition to this fundamental justification, the following additional justifications may also be useful in understanding the significance of API testing: 

4.1 API testing automation possibilities 

We may build an API testing automation suite using the many toolkits and libraries that are available to automate API requests. In the CI/CD era, that suite may be hooked while creating deployments or integrations, saving the laborious effort to test the functionality of the entire set of APIs underpinning the application. 

4.2 Quality assurance across various platforms with a single testing iteration 

When the same programme is made available for several platforms like mobile, desktop, etc., the same set of APIs is used. Therefore, when we test an API collection, we also make sure that the business logic will execute consistently across the various platforms. 

4.3 To decrease the probability of defect discovery at a later time 

Before coupling with UI components for the application, testing activities are carried out during the API testing phase. Therefore, we may already detect any flaw in the application’s basic coding at this extremely early stage. When ensuring that the API is operating correctly and error-free while accepting a reasonable set of inputs, we are also making sure that the same set of data won’t cause any issues when combined with the application user interface (UI), making any issues relatively simple to fix during the API testing phase. 

 4.4 Lowering overall testing costs 

As a basic guideline, whenever we are able to identify a defect early on, we are able to save both money and time. API testing allows us to identify bugs and defects at very early stages. 

 4.5 Security Issues 

With API testing, we can also check for security flaws by supplying a specific set of parameters that mimic the potential phishing attack methods. We may examine how the API will respond to such attacks. 

4.6 Helps in Performance check 

The API serves as a link to retrieve data from a data table after some complicated processing. It is best to wait until the specified API responds before checking the performance of the entire programme. The optimizations must be done if it doesn’t fit the criteria. 

4.7 Rapid Pace 

API tests are quick and make it easier to validate the application’s business logic, security, compliance, performance, and other elements. 

The best version of the final product must be ensured, and API implementation must function as planned in several areas such as security, performance, etc., for which API automation is necessary. Every piece of software has a single-core API, so making sure it functions properly is crucial. API testing is essential since APIs are now one of the essential components of an application, supporting the business logic. On the other side, the majority of tests just focus on the GUI components and ignore the software’s working logic.  

 Testing an API’s capacity to function under duress is one of the key components of API testing. In this context, what we call “load testing” is comparable to “performance testing,” where you run a number of test scripts, test cases, and various actions or functions while contacting the APIs and waiting for a response. Each time an API is accessed, the response received, the time it took to complete, and the performance are all recorded. 

5. Conclusion  

API testing has become an essential aspect of application testing, as it saves time and enables the creation of high-quality business logic. Unlike the time-consuming process of filling out lengthy UI forms and evaluating application behavior, API testing offers a more efficient way of testing application functionality. Automating API testing is also a straightforward process that can significantly enhance the application’s quality. 

Therefore, it’s important to include API testing in the overall test strategy for an application and conduct it alongside other types of testing. By doing so, you can ensure that the application functions seamlessly and meets the required standards. 

If you require assistance with API testing or any other type of testing, you can contact our software testing team. TestDel offers a range of testing services to help you achieve a high-quality, bug-free software project. Contact us today for more information. 

About TestDel   

At TestDel, we perform API testing for validating normal and abnormal operations and exception handling capabilities, lead to service disruptions. We will give our considerable expertise at all stages of the process and work with you on your testing requirements. We also appointed trained staff who are responsible for particular testing related roles to ensure that each part of the process goes according to standards and best practises. 

• Analyse Requirement 
• Determine test data 
• Design test strategy 
• Prepare and Execute tests 
• Defect triage 
• Prepare Defect report