BlazeMeter's Functional API Test enables you to debug your scenario by running it with one thread. The test generates a report that includes the response body, assertions, headers and some of the prominent KPIs.
There is no need to set up a different test if you already have one. You can reuse the existing BlazeMeter load test you have already configured with your script and other dependencies. Just set it to run as a 'Functional API Test'.
After checking the 'Functional API Test' option, choose a location, save and run the test.
Running the test should take about one minute, depending on the response time of course. After the response is fully retrieved, the full functional report will be presented:
The dashboard above shows how many responses passed and failed, how many errors were identified and how many assertions failed, if any. Each request is, in fact, a 'test', in this context.
Under 'Test Case', you will see the script's Thread Groups. By opening them you will see the requests they contain.
Each 'test' is a label in the test plan. When you open it, you will see a summary of this label's response time, latency, request and response sizes and the response code and message.
Let's look at the request and response of the following test.
The request data:
Looking into the request of this test, you can see the body (if you sent a body with the request), the headers and the cookies.
The response data:
Looking into the response of this test, you can see the response body, headers and you can see whether your assertion passed or failed (and why it failed):