How to convert a Gatling jsonFeeder with nested structures to json request body?

Question

I have a json feeder reading from a file a json array like this:

[{ "a": {"b": 1} }, { "a": {"b": 2} }]

When I use it for a request body it's sent like ArraySeq(HashMap(.. instead of the actual json. How can I convert the Parsed Json back to Json keeping the feeder approach?

val jsonFileFeeder = jsonFile("requests.json").circular

val scn = scenario("cost estimation")
  .feed(jsonFileFeeder)
  .exec(
    http("request_1")
      .post("/")
      .body(StringBody(
        """{
    "a":  "${a}"
}"""
      )).asJson
  )

Answer 1

Use jsonStringify(), see documentation.

val jsonFileFeeder = jsonFile("requests.json").circular

val scn = scenario("cost estimation")
  .feed(jsonFileFeeder)
  .exec(
    http("request_1")
      .post("/")
      .body(StringBody(
        """{
    "a":  "${a.jsonStringify()}"
}"""
      )).asJson
  )