public int getGatewayPortDynamically(JsonObject apiToFilePushEmulatorConfig) {
        boolean preferSecure = apiToFilePushEmulatorConfig.getBoolean("preferSecure");
        String method = preferSecure ? "https" : "http";
        return apiToFilePushEmulatorConfig.getJsonObject("verticles").getJsonObject(method).getInteger("port");
    }
get gateway port dynamically from configuration
@param apiToFilePushEmulatorConfig configuration
@return gateway port
gateway/test/src/test/java/io/apiman/gateway/test/junit/vertx3/Vertx3GatewayHelper.java