记一次 升级dubbo 2.7.7，抛出 Caused by: java.lang.IllegalStateException: zookeeper not connected

背景：apache dubbo爆出高危漏洞，需要统一升级 为最新 2.7.7

1、使用dubbo所需包,netty、dubbo、zookeeper、zk节点操作客户端

		<dependency>
            <groupId>org.apache.dubbo</groupId>
            <artifactId>dubbo</artifactId>
            <version>2.7.7</version>
            <exclusions>
                <exclusion>
                    <groupId>io.netty</groupId>
                    <artifactId>netty-all</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <!-- netty -https://mvnrepository.com/artifact/io.netty/netty-all -->
        <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-all</artifactId>
            <version>4.1.50.Final</version>
        </dependency>
        <dependency>
            <groupId>org.apache.zookeeper</groupId>
            <artifactId>zookeeper</artifactId>
            <version>3.4.14</version>
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-api</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>io.netty</groupId>
                    <artifactId>netty</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-recipes</artifactId>
            <version>4.2.0</version>
        </dependency>

2、dubbo 升级为 2.7.7 启动抛出错误。。。。导致 spring初始化中断 。。。。。emmmm

Caused by: java.lang.IllegalStateException: zookeeper not connected
	at org.apache.dubbo.remoting.zookeeper.curator.CuratorZookeeperClient.<init>(CuratorZookeeperClient.java:83)
	at org.apache.dubbo.remoting.zookeeper.curator.CuratorZookeeperTransporter.createZookeeperClient(CuratorZookeeperTransporter.java:26)
	at org.apache.dubbo.remoting.zookeeper.support.AbstractZookeeperTransporter.connect(AbstractZookeeperTransporter.java:70)
	at org.apache.dubbo.remoting.zookeeper.ZookeeperTransporter$Adaptive.connect(ZookeeperTransporter$Adaptive.java)
	at org.apache.dubbo.configcenter.support.zookeeper.ZookeeperDynamicConfiguration.<init>(ZookeeperDynamicConfiguration.java:70)
	at org.apache.dubbo.configcenter.support.zookeeper.ZookeeperDynamicConfigurationFactory.createDynamicConfiguration(ZookeeperDynamicConfigurationFactory.java:37)
	at org.apache.dubbo.common.config.configcenter.AbstractDynamicConfigurationFactory.lambda$getDynamicConfiguration$0(AbstractDynamicConfigurationFactory.java:39)
	at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1660)
	at org.apache.dubbo.common.config.configcenter.AbstractDynamicConfigurationFactory.getDynamicConfiguration(AbstractDynamicConfigurationFactory.java:39)
	at org.apache.dubbo.common.config.configcenter.DynamicConfiguration.getDynamicConfiguration(DynamicConfiguration.java:224)
	at org.apache.dubbo.config.bootstrap.DubboBootstrap.prepareEnvironment(DubboBootstrap.java:882)
	at org.apache.dubbo.config.bootstrap.DubboBootstrap.startConfigCenter(DubboBootstrap.java:605)
	at org.apache.dubbo.config.bootstrap.DubboBootstrap.useRegistryAsConfigCenterIfNecessary(DubboBootstrap.java:674)
	at org.apache.dubbo.config.bootstrap.DubboBootstrap.initialize(DubboBootstrap.java:511)
	at org.apache.dubbo.config.bootstrap.DubboBootstrap.init(DubboBootstrap.java:496)
	at org.apache.dubbo.config.ReferenceConfig.init(ReferenceConfig.java:190)
	at org.apache.dubbo.config.ReferenceConfig.get(ReferenceConfig.java:158)
	at org.apache.dubbo.config.spring.ReferenceBean.getObject(ReferenceBean.java:68)
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:178)
	... 38 common frames omitted
Caused by: java.lang.IllegalStateException: zookeeper not connected
	at org.apache.dubbo.remoting.zookeeper.curator.CuratorZookeeperClient.<init>(CuratorZookeeperClient.java:80)
	... 56 common frames omitted

细看，发现了 zookeeper.curator.CuratorZookeeperClient.(CuratorZookeeperClient.java:83)

了解下，Curator是Netflix公司开源的一套zookeeper客户端框架，解决了很多Zookeeper客户端非常底层的细节开发工作，包括连接重连、反复注册Watcher和NodeExistsException异常等等。Patrixck Hunt（Zookeeper）以一句“Guava is to Java that Curator to Zookeeper”给Curator予高度评价

猜测这块进行socket连接时出现了问题，追踪代码，，，

package org.apache.dubbo.remoting.zookeeper.curator;

public class CuratorZookeeperClient extends AbstractZookeeperClient<CuratorZookeeperClient.CuratorWatcherImpl, CuratorZookeeperClient.CuratorWatcherImpl> {
    protected static final Logger logger = LoggerFactory.getLogger(CuratorZookeeperClient.class);
    private static final String ZK_SESSION_EXPIRE_KEY = "zk.session.expire";
    static final Charset CHARSET = Charset.forName("UTF-8");
    private final CuratorFramework client;
    private Map<String, TreeCache> treeCacheMap = new ConcurrentHashMap();

    public CuratorZookeeperClient(URL url) {
        super(url);

        try {
            int timeout = url.getParameter("timeout", this.DEFAULT_CONNECTION_TIMEOUT_MS);
            int sessionExpireMs = url.getParameter("zk.session.expire", this.DEFAULT_SESSION_TIMEOUT_MS);
            Builder builder = CuratorFrameworkFactory.builder().connectString(url.getBackupAddress()).retryPolicy(new RetryNTimes(1, 1000)).connectionTimeoutMs(timeout).sessionTimeoutMs(sessionExpireMs);
            String authority = url.getAuthority();
            if (authority != null && authority.length() > 0) {
                builder = builder.authorization("digest", authority.getBytes());
            }

            this.client = builder.build();
            this.client.getConnectionStateListenable().addListener(new CuratorZookeeperClient.CuratorConnectionStateListener(url));
            this.client.start();
            boolean connected = this.client.blockUntilConnected(timeout, TimeUnit.MILLISECONDS);
            if (!connected) {
                throw new IllegalStateException("zookeeper not connected");
            }
        } catch (Exception var7) {
            throw new IllegalStateException(var7.getMessage(), var7);
        }
    }


 public synchronized boolean blockUntilConnected(int maxWaitTime, TimeUnit units) throws InterruptedException {
        long startTime = System.currentTimeMillis();
        boolean hasMaxWait = units != null;
        long maxWaitTimeMs = hasMaxWait ? TimeUnit.MILLISECONDS.convert((long)maxWaitTime, units) : 0L;

        while(!this.isConnected()) {
            if (hasMaxWait) {
                long waitTime = maxWaitTimeMs - (System.currentTimeMillis() - startTime);
                if (waitTime <= 0L) {
                    return this.isConnected();
                }

                this.wait(waitTime);
            } else {
                this.wait();
            }
        }

        return this.isConnected();
    }
    
	protected int DEFAULT_CONNECTION_TIMEOUT_MS = 5000;

发现大概意思就是超过timeout时间，没有获取连接就 直接返回。。。抛出 zookeeper not connected、而默认只有5秒。
问题已经定位，接着对症下药。

3、针对xml配置，增加timeout项 即可

 <!-- 注册中心的地址 -->
    <dubbo:registry id="dubbo1" protocol="zookeeper" address="${dubbo.registry.address}" timeout="60000"/>