1 /* 2 * Copyright 2022 The Netty Project 3 * 4 * The Netty Project licenses this file to you under the Apache License, 5 * version 2.0 (the "License"); you may not use this file except in compliance 6 * with the License. You may obtain a copy of the License at: 7 * 8 * https://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 13 * License for the specific language governing permissions and limitations 14 * under the License. 15 */ 16 package io.netty.resolver.dns; 17 18 import java.net.InetSocketAddress; 19 20 /** 21 * An infinite stream of DNS server addresses, that requests feedback to be returned to it. 22 * 23 * If query is successful timing information is provided, else a failure notification is given. 24 */ 25 public interface DnsServerResponseFeedbackAddressStream extends DnsServerAddressStream { 26 27 /** 28 * A way to provide success feedback to {@link DnsServerAddressStream} so that {@link #next()} can be tuned 29 * to return the best performing DNS server address 30 * 31 * NOTE: This is called regardless of the RCode returned by the DNS server 32 * 33 * @param address The address returned by {@link #next()} that feedback needs to be applied to 34 * @param queryResponseTimeNanos The response time of a query against the given DNS server 35 */ 36 void feedbackSuccess(InetSocketAddress address, long queryResponseTimeNanos); 37 38 /** 39 * A way to provide failure feedback to {@link DnsServerAddressStream} so that {@link #next()} cab be tuned 40 * to return the best performing DNS server address 41 * 42 * @param address The address returned by {@link #next()} that feedback needs to be applied to 43 * @param failureCause The reason the DNS query failed, can be used to penalize failures differently 44 * @param queryResponseTimeNanos The response time of a query against the given DNS server 45 */ 46 void feedbackFailure(InetSocketAddress address, Throwable failureCause, long queryResponseTimeNanos); 47 }