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Hillary Nyakundi
Hillary Nyakundi

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The Modern Rules of API Testing

In this digital age, APIs have become the cornerstone of how data is shared and processed. However, many users are often unaware of the fact that they are putting their trust in an API and not a person. This is why it's important to leverage API testing techniques to ensure that every aspect of your website or application works as expected.

Applications today are comprised of many pieces of software, each of which needs to be tested in its own way. There are always new and exciting ways to test an application and we're not just talking about checking for bugs here, it is more of the app functionality.

As technology continues to advance, the trends on how to test these applications also change. In this guide, we will be discussing the trends that apply to the testing of APIs, how they differ from other types of testing, tools we can leverage when it comes to testing APIs, and how you can stay on top of your game when it comes to API testing.

First, let's get an understanding of what we mean by APIs.

What are APIs?

APIs are designed for developers to use, and are, in essence, coding tool that allows your application to communicate with other applications. APIs allow you to integrate third-party applications into your work or use your own data and processes in the cloud.

The functionality of any application is defined by the connection it has with the outside world. For this reason, connecting your application with APIs becomes very helpful.

A very important thing to keep in mind is that when dealing with APIs we need to be sure everything works out and that we get the correct feedback before integrating them into our applications, and that's why testing them is essential.

For this reason, a vital part of testing any type of software requires evaluating whether or not there is some manner in which the app can be broken. In order to ensure a certain level of continuity when using an API in multiple ways simultaneously, one needs to conduct API testing.

Now, you have an understanding of what an API is and how it functions, and we have also introduced API testing, what exactly might we mean by this, is there more to the term testing?

What is API Testing?

API Testing

API Testing is a process that checks that an API adheres to the given requirements. Achieving this goal is not an easy task and there are many ways in which a tester could go about doing it effectively.

API testing can be conducted manually or automatically, and it is often considered a part of integration testing. Manual API testing involves directly interacting with the API using tools like API Tester or any other available online tools. API Tester is the first mobile app to test any type of API on the go. Automated API testing uses specialized software to send requests to the API and then compares the results to the expected behavior.

API testing is important because it helps ensure that the various components of a system are working together as expected. By verifying the functionality of the API, you can be confident that the system as a whole will function as intended.

API Testing tools

API testing tools are used to test the functionality of an API. They can be used to test the performance of an API, as well as to check for security vulnerabilities.

There are a number of different API testing tools available, each with its own advantages and disadvantages. Some of the most popular API testing tools include SoapUI, Postman, Runscope, and API Tester.

API testing principles

The Modern Rules of API Testing is the best way to ensure the quality of your APIs and their implementations. The rules can be applied during testing, coding, and development, as well as in production.

  1. API testing should be a part of your continuous integration and delivery pipeline
  2. API tests should be easy to maintain and write
  3. A well-designed API will make your tests easier to write
  4. You should test at the boundary of your system
  5. Keep your tests small and focused
  6. Make sure your tests are deterministic
  7. Run your tests in parallel for speed
  8. Use a tool like API Tester to simplify API testing

How to start API testing

There are many different types of tests that can be performed on an API. Functionality tests focus on ensuring that the API is able to perform its intended functions. Performance tests measure the response times of the API and check for bottlenecks. Security tests assess the vulnerability of the API to attack vectors such as SQL injection and cross-site scripting (XSS).

To get started with API testing, you will need to have access to an application with an exposed API. You will also need to choose a method for sending requests to the API (manual or automated), and select a tool or framework for writing your tests (if using automated testing). Once you have these things set up, you can begin writing your test cases and running them against the API.

API testing tips

API testing can be a challenge, but regardless of the tools you decide to use here are some tips that can help.

  1. Make sure you have a clear understanding of the API before you start testing. Read the documentation and any other available materials. This will help you know what to expect and how the API should work.

  2. Use a tool like API Tester to test the API. This will give you a better understanding of how the API works and make it easier to find any issues.

  3. Test all aspects of the API, including input validation, error handling, and security. These are all important factors in ensuring that your API is working correctly.

  4. Keep your tests up-to-date as the API changes. This will help ensure that you catch any new issues that may arise.

  5. Use mobile apps for API testing. It's a very time-changing period now, where many people are working remotely and from their phones too. By using mobile apps you can increase your productivity, get more mobility and work from anywhere in the world.

By following these tips, you can help make sure that your API testing is effective and efficient.

Conclusion

API testing is a key part of ensuring the quality of your software. By following these highlighted rules of API testing, you can make sure that your tests are up-to-date and effective.

Top comments (8)

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phophogr profile image
Phoebe Green

Nice and useful post! Especially parts with API testing tools and tips👍🏻

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magicwalter15 profile image
magicwalter15

very helpful, I'll keep it in mind

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_min_a4bc8b07de6177b694 profile image
민경 Min

Hey Lary, thanks for your post! Are there any tips for testing GraphQL APIs?

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larymak profile image
Hillary Nyakundi

I will prepare an article for the same, be on the look out

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mikedevkelly profile image
mikedevkelly

I usually use special tools (like scanners) to test Reflected Cross Site Scripting automatically. Is manually testing against XXS also a good practice?

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larymak profile image
Hillary Nyakundi

As long as you are able to validate all the input data and also make sure that only the allowlisted data is allowed you are good to go.

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alessioferrine profile image
alessioferrine

You mentioned a very interesting mobile application for testing, need to explore it better. But what tool do you regular use?

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larymak profile image
Hillary Nyakundi

I begun with Postman since it was the most common one, but currently am trying out the mobile app