Three Important Types of API Testing

The number of API tests is varied. From fuzz testing, error detection, penetration testing, functional testing, and more. Today, we are going to discuss 3 types of API tests and their importance to API providers.

Importance of API testing

In a general sense, testing needs to be done for three fundamental reasons. To validate the product, to maintain the product, and to eradicate any errors that are present. Any good API is not worth its salt if it is not reliable. That is why testing needs to be done to validate the solution.

So, what type of API tests does an API provider have to run? Although there are many tests, there is also a specialty test done on different APIs depending on their use. Let’s begin on the types of performance testing API tests.

Validation Testing

This is one of the important tests that is done in the development process. This test is done after the API’s constituent, and parts are verified. In this test, there a set of questions that are applied to the whole project. They include:

Product: is the API the correct product for the problem that it is solving? Was there any feature creep or code bloat in the API building process?

Behavior: is the correct data being accessed by the API? Is the data being accessed by the API stored with its integrity and confidentiality requirement?

Efficiency: does the API offer the most optimized, accurate, and efficient method?

These questions are used to validate the API after it has been developed against an agreed upon criteria.

Functional testing

In functional testing, the API is tested on specific functions which represent particular scenarios to ensure that it works within the expected guidelines. Additionally, errors are also tested to see if they are well handled when the results are out of the bounds of the expected parameters.

For instance, you have an API that processes music on an online portal. When a user inputs a search by the name of the track and the name of the artist, this test takes a layered approach and handles some specific instances.

Firstly, the API function is tested with the correct input, e.g. Fireflies by Owlcity. The API validates the request, but again, additional testing is required for the wrong search, e.g. Fireflies by Fireflies. For the result, we expect to see an error (the correct handling instructions and error codes) or a corrected response that has the correct response.

UI Testing

Since both functional and validation testing are generalized; UI testing is specific. This test is all about the functions of the UI. This test is concerned more with the UI and less with the API. It focuses on the general view of the usability, health, and efficiency of the back-end and front-end of the API.

In most cases, UI testing is done in place for functional testing because it serves the same function. All in all, it is important to limit UI testing to ensure that the UI functions are expected.