Application Programming Interface testing is essential to review APIs’ performance, functionality, reliability, and security. This type of software testing focuses on the business logic layer of software architecture rather than the user interface’s appearance and feel. If you are going to test APIs, there are various things you need to consider before you take the plunge. Read on to find out more.

1.    Using the Right API Testing Tools

The first thing to consider when testing APIs is the type of API testing tools you plan to use. There are literally hundreds of testing tools on the market, so it can be challenging to find the best and most suitable ones. To get started, check out this list of the best API testing tools for developers. At the top of the list are:

• RapidAPI Testing, which provides a functional testing solution for creating and managing comprehensive tests that are suitable for any type of API, such as SOAP, REST, and GraphQL.
  
• Paw, which is a full-featured MAC-native HTTP one-stop test that inspects a server’s response and can even generate code.
  
• SoapUI, which is perfect for complex test scenarios and enables developers to test SOAP, REST, or Web Services hassle-free. And you get a full source framework because SoapUI is entirely devoted to API testing.
  

2.    Using Authentication Methodology

API testing enables you to protect your application from unauthorized code access after the API layer has been put in place. You should use a robust authentication method to protect sensitive data that is to be exchanged between the user and the server. It is recommended you use a two-factor authentication technique for further effective protection.

3.    Using Subtests

By performing subtests, you can verify an API’s method, class, and package. A subtest enables you to run browser tests within other browser tests, so you can easily reuse existing workflows. If you want to reduce the amount of maintenance required in your testing suite, a subtest can help. An API subtest allows you to set up and upgrade functions and perform basic tests such as:

• Implementing new or modified core functions.
• Testing for the security of functions.
• The functionality of multiple methods for one or more APIs when using sequence mode.
  
• The functionality of selected methods when using isolation mode.
  
• The functionality of multiple-level method arguments.
  
• Recording areas that are affected by new defects.
  

4.    Using a Testing Environment Based on Scenarios

For API functions that have multiple input parameters, you should use a scenario-based testing environment. That enables you to test various input parameters at once. And because multiple input parameters handle all necessary data inputs, using a test environment based on scenarios can ensure all of your required workflows and request responses are validated during the process.

5.    Using Web Interface Verification

For complex communications, you should use a web interface verification process. Exchanging data is common between applications, the cloud, and an associated web interface, and API functions help to maintain data consistency across all channels. Ensure you consider complex scenarios that involve your app’s web interface because when you reuse existing repeatable functions, the data remains consistent across all testing channels, enabling more accurate results.