code: public static NingAsyncHttpClient defaultAsyncHttpClient(EmbeddedServer<?> server) {
  		HttpClientConfiguration configuration = HttpClientConfiguration.defaultConfiguration();
  		AsyncHttpClientConfig config = new AsyncHttpClientConfig.Builder()
  			.setFollowRedirect(configuration.isFollowRedirect())
  			.build();
  
  		return new NingAsyncHttpClient(configuration, server, new com.ning.http.client.AsyncHttpClient(config));
  	}
docs: Create new http client using internal
  http client from async-http-client library.
  An instance of {com.ning.http.client.NingAsyncHttpClient} will be automatically
  created.
  
  @param server Embedded server.
  @return Http client.
  @throws NullPointerException If {@code server} is {@code null}.