Print raw SSE push content

Hi

I am trying to test my SSE server with Gatling. Actually here is my code :

class SSE extends Simulation {

  val httpConf = http
    .baseURL("http://localhost:64096")
    .acceptEncodingHeader("gzip, deflate, br")

  val testScenario = scenario(this.getClass.getName)
    .exec(
      sse("SSE").open("/sse")
        .check(wsAwait.within(50).until(1).regex(""""event":"snapshot(.*)"""")))

    setUp(
    testScenario.inject(constantUsersPerSec(1) during(1 seconds))
  ).assertions(
  ).protocols(httpConf)
}

My regex check never passes with pattern '"""“event”:“snapshot(.)""""’ , but works for "(.)” so I want to find the issue. Is it possible to subscribe to event kind of ‘onMessage’ or smth to see raw data of SSE push? Cannot find a suitable method.

Thanks a lot.