API Testing Strategy

API testing is a type of software testing that involves testing application programming interfaces (APIs) directly and as part of integration testing to determine if they meet expectations for functionality, reliability, performance, and security. API testing is performed at the message layer Since APIs lack a GUI. API testing is critical for automating testing because APIs currently serves as the primary interface to application logic. Before deriving an API testing strategy regardless of Postman or RestAssured, identifying the testing scope is crucial.

API Testing strategy

What should be out of scope?

Any third-party interfaces. Most of the applications will have one or more third-party interfaces that should be out of scope for API testing. Assume one such interface is Google Pay, so scenarios can keep testing payment with insufficient balance or invalid card out of the range. These are functionalities provided by the payment provider.

What should be in scope?

A good approach will be to increase the scope as the testing progress successfully. Organize the API testing at each level will help in achieving this. Testing the contract can be an example of level one testing. Such tests should validate that the agreements are documented as per the specifications and can consume those API. A good example will be the usage…