Types Of API Testing

API testing significantly contributes to applications being reliable, secure, functional, and efficient by assessing the communication routes between software components.

Everything that communicates on the internet these days is talking to an API (Application Programming Interface) and as we implement them in our technologies we also need to take API testing into account. As with everything, our API’s need to be tested properly and thoroughly on many different quality characteristics because if we think about it. Not only should we pay close attention to the functional requirements but we should also pay the appropriate amount of attention to non-functional requirements.

API testing entails various different aspects and goes much further than simply executing a few test cases. Testing needs to start at the earliest possible stage and continue on until the production release.

API testing is also essential for ensuring API security and stability. It’s integral to getting your product to market and ensuring your users and customers get the best possible service.

API documentation is a set of human-readable instructions for using and integrating with an API.

API documentation includes detailed information about an API’s available endpoints, methods, resources, authentication protocols, parameters, and headers, as well as examples of common requests and responses. Effective API documentation improves the developer experience for private, partner, and public APIs, but it also offers distinct benefits for each API type.

Types of API Testing :

🔹 Validation Testing

Testing an API’s conformance to specified system requirements and standards is the first step in this process.

With this test, a basic check is established to support more in-depth testing efforts.

🔹 Performance Testing

It evaluates an API’s speed, responsiveness, and stability under various conditions to ensure it meets benchmarks and user expectations.

Postman has a neat feature to simulate real-world traffic on your local machine to performance test your APIs. Learn more here: https://blog.postman.com/postman-api-performance-testing/

🔹 Security Testing

This testing identifies vulnerabilities that could potentially lead to unauthorized access or data breaches.

It involves rigorous checks to ensure security measures are robust enough to thwart attacks and prevent data leaks.

It employs techniques like penetration testing and fuzz testing to identify vulnerabilities.

🔹 Functional Testing

An API’s operational capabilities are evaluated through functional testing to make sure it performs as planned under various circumstances and appropriately answers requests.

Evaluating the functional integrity and business logic of the API are its main objectives.

🔹 Reliability Testing

Assesses an API’s ability to perform consistently over time.

This testing identifies potential failures to ensure stability and dependability under various conditions. It helps maintain software trustworthiness and user satisfaction by exposing and correcting reliability issues.

🔹 Integration Testing

To make sure the API operates consistently across various software modules, integration testing assesses how well it communicates with other system elements.

It confirms stable system performance and smooth integration.

🔹 Load Testing

Load testing is very similar to performance testing because we are trying to emulate production like traffic but instead of creating spikes in traffic we want to emulate a constant steady stream of traffic at a normally expected rate. This is to ensure that the API’s do not contain memory leaks or other similar defects that might cause issues after running for a prolonged period of time.

Get started with API testing.

Define the API requirements before getting start to testing of APIs, such as :

- What will this API be used for
- How will the application handle data
- How will the system handle failure
- How will the system handle output
- How will the system handle unexpected input
- What are the requirements for the fields the API sends out and receives
- How the API will interact with other APIs, such as which protocol will be used
- Entry and exit criteria
- The pass and fail criteria for the API/feature

Happy Reading!