Gatling Verifying Decoded JWT token

Question

I'm trying to decode a JWT token returned, and check the sub claim for if it matches the username. But I can't seem to find the syntax to do so.

...
      .check(status.is(HttpResponseStatus.OK.code()))
      .check(jsonPath("$.access_token").saveAs("access_token"))
      .check(jsonPath("$.refresh_token").exists)
      .check(JWSObject.parse("${access_token}").getPayload.toJSONObject.get("sub").toString.substring("$username"))

I'm getting errors around it expecting a HttpCheck, is there a HTTPCheck for this type?

Thanks

Answer 1

This is pretty much exactly what.transform is for. You extract the token with jsonPath, do a transform to get the sub, and then assert that it matches the username.

(I have not tried the actual jwt extract / validation)

.check(jsonPath("$.access_token").transform(jwt => JWT.decode(jwt).getClaim("sub").asString()).is("${username}")