springboot eureka 注册服务探索

╰+攻爆jí腚メ 2022-05-23 09:20 219阅读 0赞

运行时日志
    2018-03-09 13:16:42.132  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 0ms
    2018-03-09 13:17:42.141  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 7ms
    2018-03-09 13:18:42.147  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 5ms
    2018-03-09 13:19:42.155  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 6ms
    2018-03-09 13:20:03.562  INFO 13652 --- [trap-executor-0] c.n.d.s.r.aws.ConfigClusterResolver      : Resolving eureka endpoints via configuration
    2018-03-09 13:20:42.159  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 2ms
    2018-03-09 13:21:42.160  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 0ms
    2018-03-09 13:22:42.163  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 1ms
    2018-03-09 13:23:42.165  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 0ms
    2018-03-09 13:24:42.165  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 0ms
    2018-03-09 13:25:03.584  INFO 13652 --- [trap-executor-0] c.n.d.s.r.aws.ConfigClusterResolver      : Resolving eureka endpoints via configuration
    
    注册服务日志
    2018-03-09 13:25:42.169  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 2ms
    2018-03-09 13:26:37.169  INFO 13652 --- [ XNIO-2 task-32] c.n.e.registry.AbstractInstanceRegistry  : Registered instance EES-HOTEL/16101164-15-PC:ees-hotel:8119 with status UP (replication=[true/false])
    2018-03-09 13:26:42.169  INFO 13652 --- [a-EvictionTimer] c.n.e.registry.AbstractInstanceRegistry  : Running the evict task with compensationTime 0ms
    PATH:
    AbstractInstanceRegistry : com.netflix.eureka:eureka-core 1.6.2

#跟代码
    com.netflix.eureka.registry.AbstractInstanceRegistry.register(InstanceInfo registrant, int leaseDuration, boolean isReplication)//注册信息，注册信息持续时间 默认120，是否复制
    1.加同步锁读取锁
    2.在该类的常量registry（ConcurrentHashMap<String, Map<String, Lease<InstanceInfo>>>）根据取服务名（spring:  application:  name: eureka ）获取所有注册机（ rtn:Map<String, Lease<InstanceInfo>> gMap）
    3.=====（监听）EurekaMonitors.REGISTER.increment(isReplication); 监听注册服务的个数，增加服务计数（EurekaMonitors的myZoneCounter属性），isReplication为falses时才进行计数增长。//主要是对 AtomicLong[extends Number implements java.io.Serializable]内的unsafe常量
    4.判断2是否获取到有效eureka服务，若没有则
    if (gMap == null) {
        ConcurrentHashMap<String, Lease<InstanceInfo>> gNewMap = new ConcurrentHashMap();
        gMap = (Map)this.registry.putIfAbsent(registrant.getAppName(), gNewMap);
        if (gMap == null) {
            gMap = gNewMap;
        }
    }
    5.获取existingLease(生存周期)信息，从2返回的map内，根据注册信息(instanceId[16101164-15-PC:eureka:8001]或eureka.instance.hostName[eureka1])，Lease<InstanceInfo> existingLease = (Lease)((Map)gMap).get(registrant.getId());
    if (existingLease != null && existingLease.getHolder() != null) {
        Long existingLastDirtyTimestamp = ((InstanceInfo)existingLease.getHolder()).getLastDirtyTimestamp();
        Long registrationLastDirtyTimestamp = registrant.getLastDirtyTimestamp();
        logger.debug("Existing lease found (existing={}, provided={}", existingLastDirtyTimestamp, registrationLastDirtyTimestamp);
        if (existingLastDirtyTimestamp > registrationLastDirtyTimestamp) {
            logger.warn("There is an existing lease and the existing lease's dirty timestamp {} is greater than the one that is being registered {}", existingLastDirtyTimestamp, registrationLastDirtyTimestamp);
            logger.warn("Using the existing instanceInfo instead of the new instanceInfo as the registrant");
            registrant = (InstanceInfo)existingLease.getHolder();
        }
    } else {
        Object var6 = this.lock;
        synchronized(this.lock) {
            if (this.expectedNumberOfRenewsPerMin > 0) {
                this.expectedNumberOfRenewsPerMin += 2;
                this.numberOfRenewsPerMinThreshold = (int)((double)this.expectedNumberOfRenewsPerMin * this.serverConfig.getRenewalPercentThreshold());
            }
        }
    
        logger.debug("No previous lease information found; it is new registration");
    }
    Lease<InstanceInfo> lease = new Lease(registrant, leaseDuration);
    if (existingLease != null) {
            lease.setServiceUpTimestamp(existingLease.getServiceUpTimestamp());
    }
    6.获取最近注册队列recentRegisteredQueue【AbstractInstanceRegistry.CircularQueue<Pair<Long, String>>】，
    对队列加锁，将待注册的服务信息注册（当前系统时间戳 ，当前待注册服务名eg:ees-hotel + id(instanceId/hostName)），
    synchronized(this.recentRegisteredQueue) {
        this.recentRegisteredQueue.add(new Pair(System.currentTimeMillis(), registrant.getAppName() + "(" + registrant.getId() + ")"));
    }
    
    7.注册信息的overriddenStatus状态不是InstanceStatus.UNKNOWN时，将当前服务注册信息内的此状态维护到overriddenInstanceStatusMap，key为id.
    8.将overriddenInstanceStatusMap内的OverriddenStatus同步到注册信息registrant内，当overriddenStatusFromMap内存在此状态时。
    9.当注册信息registrant的状态为InstanceStatus.UP时，更新lease的存活【租约】时间，服务开始时间为当前时间戳。
    10.注册信息的actionType设置为在发现服务中添加，将当前注册的服务添加到服务发现内。
    11.将新注册（更改）的服务信息（lease）添加到最近更改队列（recentlyChangedQueue）
    12.设置新注册的服务的最后更新时间
    13.this.invalidateCache(registrant.getAppName(), registrant.getVIPAddress(), registrant.getSecureVipAddress()); 使缓存无效
    缓存使用的是Google的private final LoadingCache<Key, ResponseCacheImpl.Value> readWriteCacheMap; 该接口继承Cache,存在invalidate抽象方法，实际调用LocalCache.LocalManualCache.invalidate,如下
    public void invalidate(Object key) {
        Preconditions.checkNotNull(key);
        this.localCache.remove(key);
    }
    其中使用Preconditions的checkNotNull做非空校验
    最后在final LocalCache<K, V> localCache;内删除缓存的信息。
    LoadingCache extends Cache,Function 
    LocalCache implements Cache
    LocalManualCache implements Cache
    Manual内操作
    
    此处删除缓存是循环操作，在初次启动时会删除
    this.invalidate(new Key(EntityType.Application, appName, type, v, EurekaAccept.full), new Key(EntityType.Application, appName, type, v, EurekaAccept.compact), new Key(EntityType.Application, "ALL_APPS", type, v, EurekaAccept.full), new Key(EntityType.Application, "ALL_APPS", type, v, EurekaAccept.compact), new Key(EntityType.Application, "ALL_APPS_DELTA", type, v, EurekaAccept.full), new Key(EntityType.Application, "ALL_APPS_DELTA", type, v, EurekaAccept.compact));
    
    ResponseCacheImpl构造方法会初始化readWriteCacheMap，initialCapacity=1000
    this.readWriteCacheMap = CacheBuilder.newBuilder().initialCapacity(1000).expireAfterWrite(serverConfig.getResponseCacheAutoExpirationInSeconds(), TimeUnit.SECONDS).removalListener(new RemovalListener<Key, ResponseCacheImpl.Value>() {
        public void onRemoval(RemovalNotification<Key, ResponseCacheImpl.Value> notification) {
            Key removedKey = (Key)notification.getKey();
            if (removedKey.hasRegions()) {
                Key cloneWithNoRegions = removedKey.cloneWithoutRegions();
                ResponseCacheImpl.this.regionSpecificKeys.remove(cloneWithNoRegions, removedKey);
            }
    
        }
    }).build(new CacheLoader<Key, ResponseCacheImpl.Value>() {
        public ResponseCacheImpl.Value load(Key key) throws Exception {
            if (key.hasRegions()) {
                Key cloneWithNoRegions = key.cloneWithoutRegions();
                ResponseCacheImpl.this.regionSpecificKeys.put(cloneWithNoRegions, key);
            }
    
            ResponseCacheImpl.Value value = ResponseCacheImpl.this.generatePayload(key);
            return value;
        }
    });

未完待续