In the last chapter, we fixed the issues that we had identified and completed the remaining things in our RESTful web service. However, to ensure quality we need to test our endpoints, and manual testing is not enough. In real-world projects, we can't test each endpoint repeatedly because in the real world there are a lot more endpoints. So, we move towards automated testing. We write test cases and execute them in an automated way. In fact, it makes more sense to write test cases first, run them, and then write code to fulfill the requirements that test. This method of development is called TDD (Test-driven Development).
TDD is good and ensures that we are working exactly according to our test cases. However, in this book, we didn't use TDD because there were a lot of things to understand and we didn't want to include one more thing at the same time. So now, when we are done with the concepts, understanding, and writing the RESTful web service...