How can you automate API testing in 5 easy steps?

2 Define your API testing strategy

When defining an API testing strategy, it is important to consider the scope of the tests, the data needed to send and receive from the APIs, the environment in which the tests are run, how they are triggered and executed, and how to collect and analyze results. Prioritizing test functionalities and scenarios is also key, as well as generating, storing, and managing data. Moreover, scheduling and integrating API tests with other tests and tools, as well as communicating and sharing results with the team and stakeholders should be taken into account.

3 Design your API test cases

The third step is to design your API test cases, which means defining the inputs, outputs, and assertions for each API request and response. It's important to use realistic and valid data for your API test cases, and utilize variables and parameters to make them reusable and dynamic. Assertions should be used to verify the expected status codes, headers, bodies, and schemas of your API responses. Additionally, preconditions and postconditions should be used to set up and clean up your API test cases. Finally, naming conventions and descriptions should be used to organize and document your API test cases so that they are easy to understand and maintain.

4 Implement your API test cases

The fourth step is to implement your API test cases, which involves writing the code or scripts that execute your API requests and validate your API responses. Depending on the tool you use, you may have different options and languages for implementation. For instance, Postman offers JavaScript and the built-in Postman Sandbox, while Rest-Assured offers Java and a fluent DSL. It's important to follow some coding standards and guidelines when writing API test cases. This includes using modular and reusable functions and methods to structure and simplify your code, as well as including comments and annotations to explain and document it. Error handling and logging should be used to handle any exceptions or failures in your API test cases, while version control and code review should be employed to manage and improve them. Doing so will help ensure that your API test cases are consistent and reliable.

5 Run and monitor your API test cases

The fifth and final step is to run and monitor your API test cases. This involves executing requests and checking responses, collecting metrics and feedback, and using them to improve API quality and performance. You should run API test cases regularly and frequently, in different environments, with configuration files and variables. To scale them, consider running in parallel or distributed modes on cloud platforms. Additionally, monitor API test cases in real-time or historical modes with dashboards and reports. Lastly, measure functional and non-functional aspects using tools and techniques.