Using assertions and matchers on the response
So far, we are not really doing any testing concerning the returned data but only the status code. To fulfill the title of our scenario (Checking user-specific posts), we must add at least one other step with an assertion so this can be a real test.
JSON examples
All examples in this chapter apply to JSON data since this is the most common REST API request-and-response format. For XML-based APIs, the shown approaches are almost identical. More on working with matchers on XML data can be found here: https://github.com/karatelabs/karate#xpath-functions.
From our API exploration and its documentation, we know that the endpoint in use returns a list of posts where each one has a userId that should be equal to the one that we pass via the request parameter. Additionally, it has an id that can identify each post, title, and body. The following is an example structure of a posts resource:
{
"userId"...