A little repo with bunch of tests of https://petstore.swagger.io/ api using jest and supertest.
Use yarn or npm install to install dependencies, then yarn test or npm test to run tests.
There are few tests that checks basic functionalities of /pet. There are two tests at the very beginning that verifies if POST request is processed correctly. Ideally, every single endpoint and method should be tested that way, using incorrect or empty data. As I noticed that there is no real validation or processing on server side, I have not implemented any more test scenarios, but they would look like the ones I provided.
In other test cases I focused on main purpose of each method in /pet endpoint (GET, PUT, POST, DELETE) with verification if the data are saved correctly. I used only name and availability fields, all other data could be tested the same way. Before each test, new "pet" is created using POST /pet to make sure fresh data is provided for each test.
In my opinion tests (and any code) should be clean and as simple as possible. Because of that I decided not to use Cucumber. Cucumber adds additional layer of abstraction, which in case of such simple example as this one is overkill. I could find Cucumber useful in case if we don't have real documentation or test cases written down elsewehere and Cucumber scenarious would become our documentation. In this particular example documentation is available in swagger and test cases are pretty self-explanatory.