API stands for Application Programming Interface which allows software applications to communicate with each other via API calls. Postman is currently one of the most popular tools used in API testing. It was introduced in 2012.
API Testing is an integral part of the software quality assurance process. You need the right approach and tool to improve your testing outcomes. The more your testing process is structured; the better will be the outcomes of the testing.
An API indicates how one software program should interact with another software program. API acts as an interface between two software applications by allowing them to communicate with each other.
API testing is a type of integration testing that is performed to test the API to validate its functionality, reliability, performance, and security of the application for which API is used. In this testing, the APIs and the integrations they enable are tested.
Types of API testing
In this testing, the following types of testing are conducted:
Unit Testing: Unit testing is a level of software testing where individual units/ components of the software are tested.
Functionality Testing: Functionality Testing is a type of software testing whereby the system is tested against the functional requirements/specifications.
Load Testing: For testing the functionality and performance under load conditions.
Error Detection: For identifying any errors such as exceptions and data leaks.
Security Testing: For testing that the API is secure against any external threats.
UI Testing: For testing the functionality of the user interfaces as part of end-to-end integration tests to ensure the UI functions as expected.
Interoperability & Compliance testing: Interoperability testing is defined as a software testing type, that checks whether the software can interoperate with other software components, software’s or systems.
Penetration Testing: For detecting any vulnerabilities of an application from attackers.
Fuzz Testing: For testing the API by giving inputs in an attempt to crash it.
API Testing Approach
API testing is performed as Black Box Testing by the QA team. This testing is conducted post the build is ready. The source code is not included in this testing.
In this testing, a request is sent to the API with known to analyze the response that includes:
Types of bugs found in API testing
Following are the types of bugs found: