Java tutorial
/* * (C) Copyright 2015-2016 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * * Contributors: * ohun@live.cn () */ package com.mpush.common.net; import com.google.common.collect.Lists; import com.google.common.collect.Maps; import com.mpush.api.service.BaseService; import com.mpush.api.service.Listener; import com.mpush.api.spi.Spi; import com.mpush.api.spi.common.ServiceDiscoveryFactory; import com.mpush.api.spi.net.DnsMapping; import com.mpush.api.spi.net.DnsMappingManager; import com.mpush.api.srd.ServiceDiscovery; import com.mpush.api.srd.ServiceListener; import com.mpush.api.srd.ServiceNode; import com.mpush.tools.Jsons; import com.mpush.tools.config.CC; import com.mpush.tools.thread.NamedPoolThreadFactory; import com.mpush.tools.thread.ThreadNames; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.TimeUnit; import static com.mpush.api.srd.ServiceNames.DNS_MAPPING; import static com.mpush.tools.Utils.checkHealth; @Spi(order = 1) public class HttpProxyDnsMappingManager extends BaseService implements DnsMappingManager, Runnable, ServiceListener { private final Logger logger = LoggerFactory.getLogger(HttpProxyDnsMappingManager.class); protected final Map<String, List<DnsMapping>> mappings = Maps.newConcurrentMap(); private final Map<String, List<DnsMapping>> all = Maps.newConcurrentMap(); private Map<String, List<DnsMapping>> available = Maps.newConcurrentMap(); private ScheduledExecutorService executorService; @Override protected void doStart(Listener listener) throws Throwable { ServiceDiscovery discovery = ServiceDiscoveryFactory.create(); discovery.subscribe(DNS_MAPPING, this); discovery.lookup(DNS_MAPPING).forEach(this::add); if (all.size() > 0) { executorService = Executors .newSingleThreadScheduledExecutor(new NamedPoolThreadFactory(ThreadNames.T_HTTP_DNS_TIMER)); executorService.scheduleAtFixedRate(this, 1, 20, TimeUnit.SECONDS); //20 ??dns } listener.onSuccess(); } @Override protected void doStop(Listener listener) throws Throwable { if (executorService != null) { executorService.shutdown(); } listener.onSuccess(); } @Override public void init() { all.putAll(CC.mp.http.dns_mapping); available.putAll(CC.mp.http.dns_mapping); } @Override public boolean isRunning() { return executorService != null && !executorService.isShutdown(); } public void update(Map<String, List<DnsMapping>> nowAvailable) { available = nowAvailable; } public Map<String, List<DnsMapping>> getAll() { return all; } public DnsMapping lookup(String origin) { List<DnsMapping> list = mappings.get(origin); if (list == null || list.isEmpty()) { if (available.isEmpty()) return null; list = available.get(origin); } if (list == null || list.isEmpty()) return null; int L = list.size(); if (L == 1) return list.get(0); return list.get((int) (Math.random() * L % L)); } @Override public void run() { logger.debug("do dns mapping checkHealth ..."); Map<String, List<DnsMapping>> all = this.getAll(); Map<String, List<DnsMapping>> available = Maps.newConcurrentMap(); all.forEach((key, dnsMappings) -> { List<DnsMapping> okList = Lists.newArrayList(); dnsMappings.forEach(dnsMapping -> { if (checkHealth(dnsMapping.getIp(), dnsMapping.getPort())) { okList.add(dnsMapping); } else { logger.warn("dns can not reachable:" + Jsons.toJson(dnsMapping)); } }); available.put(key, okList); }); this.update(available); } @Override public void onServiceAdded(String path, ServiceNode node) { add(node); } @Override public void onServiceUpdated(String path, ServiceNode node) { add(node); } @Override public void onServiceRemoved(String path, ServiceNode node) { mappings.computeIfAbsent(node.getAttr("origin"), k -> new ArrayList<>()) .remove(new DnsMapping(node.getHost(), node.getPort())); } private void add(ServiceNode node) { mappings.computeIfAbsent(node.getAttr("origin"), k -> new ArrayList<>()) .add(new DnsMapping(node.getHost(), node.getPort())); } }