What QA forgot to test when testing API

As the world moves towards more distributed and interconnected systems, REST APIs have become the de facto standard for communication between applications. REST (Representational State Transfer) APIs are simple, lightweight, and widely adopted, making them an ideal choice for building modern web applications. However, even the most well-designed REST APIs can have issues that may go unnoticed during testing.

3/24/20232 min read

  1. Error Handling One of the essential aspects of any REST API is its ability to handle errors. Testers need to ensure that the API can handle various types of errors, such as invalid input, unexpected data, and server-side errors. It is essential to test that the API returns the correct error messages and codes to the client, allowing the client application to handle the error appropriately.

  2. Authentication and Authorization Another critical area that testers may overlook is the authentication and authorization mechanism of the API. Testers need to ensure that the API correctly handles authentication failures and that only authorized users have access to specific resources. It is essential to verify that the API returns the correct status codes and messages when authentication and authorization fails.

  3. Performance is a critical non-functional requirement for any REST API. Testers need to test the API's performance under different loads and traffic patterns, ensuring that it can handle a high number of requests and responses without slowing down or crashing. It is also essential to verify that the API can handle various types of payloads, such as large files or complex JSON objects, without any significant degradation in performance.

  4. Data Integrity REST APIs often deal with sensitive data, and it is crucial to ensure that the API maintains data integrity. Testers need to verify that the API correctly updates, deletes, and retrieves data from the system without compromising its consistency or accuracy. It is also essential to ensure that the API handles concurrent requests correctly and that data updates are atomic.

  5. Security & Compliance: Ensure that the API is compliant with relevant security standards such as OWASP, PCI-DSS, and HIPAA. Ensure that input data is validated to prevent SQL injection, cross-site scripting (XSS), and other types of attacks. Check that the API has rate limiting in place to prevent denial-of-service (DoS) attacks.

In conclusion, REST API testing is a complex and challenging process that requires careful planning and execution. Testers need to ensure that they cover all necessary areas of testing, including both functional and non-functional requirements. By paying attention to the critical areas discussed in this blog post, Test Spread can help ensure that REST APIs are reliable, secure, and performant.