## 一、ACL（Access contol List）
什么是ACL，Zookeeper作为一个分布式协调框架，其内部存储的都是一些关乎分布式系统运行时状态的元数据
，尤其是设计到了一些分布式锁，Master选举和协调应用场景，有效的保障Zookeeper中的数据安全，Zookeeper
ZK提供了三种模式，权限模式，授权对象，权限
权限模式：Scheme 开发人员最多使用的如下四种权限模式
IP: ip模式通过ip地址，来进行权限控制
Digest： digest是最常用的权限控制模式，zk会对形成的权限标识先后进行两次编码处理，分别是SHA-1加密 算法、BASE64编码。
World：World是一值最开放的权限控制模式、这种模式可以看做为特殊的Digest，他仅仅是一个标识而已
Super：超级用户模式，在超级用户模式下可以ZK进行操作
权限： 权限就是指那些通过权限检测后可以允许执行的操作，在ZK中，对数据的操作权限分为以下五大类
CREATE、Delete、READ、WRITE、ADMIN
## 二、代码的实现
/**
* Zookeeper 节点授权
* @author（alienware）
* @since 2015-6-14
*/
public class ZookeeperAuth implements Watcher {
/** 连接地址 */
final static String CONNECT_ADDR = "192.168.80.88:2181";
/** 测试路径 */
final static String PATH = "/testAuth";
final static String PATH_DEL = "/testAuth/delNode";
/** 认证类型 */
final static String authentication_type = "digest";
/** 认证正确方法 */
final static String correctAuthentication = "123456";
/** 认证错误方法 */
final static String badAuthentication = "654321";
static ZooKeeper zk = null;
/** 计时器 */
AtomicInteger seq = new AtomicInteger();
/** 标识 */
private static final String LOG_PREFIX_OF_MAIN = "【Main】";
private CountDownLatch connectedSemaphore = new CountDownLatch(1);
@Override
public void process(WatchedEvent event) {
try {
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (event==null) {
return;
}
// 连接状态
KeeperState keeperState = event.getState();
// 事件类型
EventType eventType = event.getType();
// 受影响的path
String path = event.getPath();
String logPrefix = "【Watcher-" + this.seq.incrementAndGet() + "】";
System.out.println(logPrefix + "收到Watcher通知");
System.out.println(logPrefix + "连接状态:\t" + keeperState.toString());
System.out.println(logPrefix + "事件类型:\t" + eventType.toString());
if (KeeperState.SyncConnected == keeperState) {
// 成功连接上ZK服务器
if (EventType.None == eventType) {
System.out.println(logPrefix + "成功连接上ZK服务器");
connectedSemaphore.countDown();
}
} else if (KeeperState.Disconnected == keeperState) {
System.out.println(logPrefix + "与ZK服务器断开连接");
} else if (KeeperState.AuthFailed == keeperState) {
System.out.println(logPrefix + "权限检查失败");
} else if (KeeperState.Expired == keeperState) {
System.out.println(logPrefix + "会话失效");
}
System.out.println("--------------------------------------------");
}
/**
* 创建ZK连接
*
* @param connectString
* ZK服务器地址列表
* @param sessionTimeout
* Session超时时间
*/
public void createConnection(String connectString, int sessionTimeout) {
this.releaseConnection();
try {
zk = new ZooKeeper(connectString, sessionTimeout, this);
//添加节点授权
zk.addAuthInfo(authentication_type,correctAuthentication.getBytes());
System.out.println(LOG_PREFIX_OF_MAIN + "开始连接ZK服务器");
//倒数等待
connectedSemaphore.await();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 关闭ZK连接
*/
public void releaseConnection() {
if (this.zk!=null) {
try {
this.zk.close();
} catch (InterruptedException e) {
}
}
}
/**
*
* <B>方法名称：</B>测试函数<BR>
* <B>概要说明：</B>测试认证<BR>
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
ZookeeperAuth testAuth = new ZookeeperAuth();
testAuth.createConnection(CONNECT_ADDR,2000);
List<ACL> acls = new ArrayList<ACL>(1);
for (ACL ids_acl : Ids.CREATOR_ALL_ACL) {
acls.add(ids_acl);
}
try {
zk.create(PATH, "init content".getBytes(), acls, CreateMode.PERSISTENT);
System.out.println("使用授权key：" + correctAuthentication + "创建节点："+ PATH + ", 初始内容是: init content");
} catch (Exception e) {
e.printStackTrace();
}
try {
zk.create(PATH_DEL, "will be deleted! ".getBytes(), acls, CreateMode.PERSISTENT);
System.out.println("使用授权key：" + correctAuthentication + "创建节点："+ PATH_DEL + ", 初始内容是: init content");
} catch (Exception e) {
e.printStackTrace();
}
// 获取数据
getDataByNoAuthentication();
getDataByBadAuthentication();
getDataByCorrectAuthentication();
// 更新数据
updateDataByNoAuthentication();
updateDataByBadAuthentication();
updateDataByCorrectAuthentication();
// 删除数据
deleteNodeByBadAuthentication();
deleteNodeByNoAuthentication();
deleteNodeByCorrectAuthentication();
//
Thread.sleep(1000);
deleteParent();
//释放连接
testAuth.releaseConnection();
}
/** 获取数据：采用错误的密码 */
static void getDataByBadAuthentication() {
String prefix = "[使用错误的授权信息]";
try {
ZooKeeper badzk = new ZooKeeper(CONNECT_ADDR, 2000, null);
//授权
badzk.addAuthInfo(authentication_type,badAuthentication.getBytes());
Thread.sleep(2000);
System.out.println(prefix + "获取数据：" + PATH);
System.out.println(prefix + "成功获取数据：" + badzk.getData(PATH, false, null));
} catch (Exception e) {
System.err.println(prefix + "获取数据失败，原因：" + e.getMessage());
}
}
/** 获取数据：不采用密码 */
static void getDataByNoAuthentication() {
String prefix = "[不使用任何授权信息]";
try {
System.out.println(prefix + "获取数据：" + PATH);
ZooKeeper nozk = new ZooKeeper(CONNECT_ADDR, 2000, null);
Thread.sleep(2000);
System.out.println(prefix + "成功获取数据：" + nozk.getData(PATH, false, null));
} catch (Exception e) {
System.err.println(prefix + "获取数据失败，原因：" + e.getMessage());
}
}
/** 采用正确的密码 */
static void getDataByCorrectAuthentication() {
String prefix = "[使用正确的授权信息]";
try {
System.out.println(prefix + "获取数据：" + PATH);
System.out.println(prefix + "成功获取数据：" + zk.getData(PATH, false, null));
} catch (Exception e) {
System.out.println(prefix + "获取数据失败，原因：" + e.getMessage());
}
}
/**
* 更新数据：不采用密码
*/
static void updateDataByNoAuthentication() {
String prefix = "[不使用任何授权信息]";
System.out.println(prefix + "更新数据： " + PATH);
try {
ZooKeeper nozk = new ZooKeeper(CONNECT_ADDR, 2000, null);
Thread.sleep(2000);
Stat stat = nozk.exists(PATH, false);
if (stat!=null) {
nozk.setData(PATH, prefix.getBytes(), -1);
System.out.println(prefix + "更新成功");
}
} catch (Exception e) {
System.err.println(prefix + "更新失败，原因是：" + e.getMessage());
}
}
/**
* 更新数据：采用错误的密码
*/
static void updateDataByBadAuthentication() {
String prefix = "[使用错误的授权信息]";
System.out.println(prefix + "更新数据：" + PATH);
try {
ZooKeeper badzk = new ZooKeeper(CONNECT_ADDR, 2000, null);
//授权
badzk.addAuthInfo(authentication_type,badAuthentication.getBytes());
Thread.sleep(2000);
Stat stat = badzk.exists(PATH, false);
if (stat!=null) {
badzk.setData(PATH, prefix.getBytes(), -1);
System.out.println(prefix + "更新成功");
}
} catch (Exception e) {
System.err.println(prefix + "更新失败，原因是：" + e.getMessage());
}
}
/**
* 更新数据：采用正确的密码
*/
static void updateDataByCorrectAuthentication() {
String prefix = "[使用正确的授权信息]";
System.out.println(prefix + "更新数据：" + PATH);
try {
Stat stat = zk.exists(PATH, false);
if (stat!=null) {
zk.setData(PATH, prefix.getBytes(), -1);
System.out.println(prefix + "更新成功");
}
} catch (Exception e) {
System.err.println(prefix + "更新失败，原因是：" + e.getMessage());
}
}
/**
* 不使用密码 删除节点
*/
static void deleteNodeByNoAuthentication() throws Exception {
String prefix = "[不使用任何授权信息]";
try {
System.out.println(prefix + "删除节点：" + PATH_DEL);
ZooKeeper nozk = new ZooKeeper(CONNECT_ADDR, 2000, null);
Thread.sleep(2000);
Stat stat = nozk.exists(PATH_DEL, false);
if (stat!=null) {
nozk.delete(PATH_DEL,-1);
System.out.println(prefix + "删除成功");
}
} catch (Exception e) {
System.err.println(prefix + "删除失败，原因是：" + e.getMessage());
}
}
/**
* 采用错误的密码删除节点
*/
static void deleteNodeByBadAuthentication() throws Exception {
String prefix = "[使用错误的授权信息]";
try {
System.out.println(prefix + "删除节点：" + PATH_DEL);
ZooKeeper badzk = new ZooKeeper(CONNECT_ADDR, 2000, null);
//授权
badzk.addAuthInfo(authentication_type,badAuthentication.getBytes());
Thread.sleep(2000);
Stat stat = badzk.exists(PATH_DEL, false);
if (stat!=null) {
badzk.delete(PATH_DEL, -1);
System.out.println(prefix + "删除成功");
}
} catch (Exception e) {
System.err.println(prefix + "删除失败，原因是：" + e.getMessage());
}
}
/**
* 使用正确的密码删除节点
*/
static void deleteNodeByCorrectAuthentication() throws Exception {
String prefix = "[使用正确的授权信息]";
try {
System.out.println(prefix + "删除节点：" + PATH_DEL);
Stat stat = zk.exists(PATH_DEL, false);
if (stat!=null) {
zk.delete(PATH_DEL, -1);
System.out.println(prefix + "删除成功");
}
} catch (Exception e) {
System.out.println(prefix + "删除失败，原因是：" + e.getMessage());
}
}
/**
* 使用正确的密码删除节点
*/
static void deleteParent() throws Exception {
try {
Stat stat = zk.exists(PATH_DEL, false);
if (stat == null) {
zk.delete(PATH, -1);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
