## 一、ACL（Access contol List）
什么是ACL，Zookeeper作為一個分布式協調框架，其內部存儲的都是一些關乎分布式系統運行時狀態的元數據
，尤其是設計到了一些分布式鎖，Master選舉和協調應用場景，有效的保障Zookeeper中的數據安全，Zookeeper
ZK提供了三種模式，權限模式，授權對象，權限
權限模式：Scheme 開發人員最多使用的如下四種權限模式
IP: ip模式通過ip地址，來進行權限控制
Digest： digest是最常用的權限控制模式，zk會對形成的權限標識先后進行兩次編碼處理，分別是SHA-1加密 算法、BASE64編碼。
World：World是一值最開放的權限控制模式、這種模式可以看做為特殊的Digest，他僅僅是一個標識而已
Super：超級用戶模式，在超級用戶模式下可以ZK進行操作
權限： 權限就是指那些通過權限檢測后可以允許執行的操作，在ZK中，對數據的操作權限分為以下五大類
CREATE、Delete、READ、WRITE、ADMIN
## 二、代碼的實現
/**
* Zookeeper 節點授權
* @author（alienware）
* @since 2015-6-14
*/
public class ZookeeperAuth implements Watcher {
/** 連接地址 */
final static String CONNECT_ADDR = "192.168.80.88:2181";
/** 測試路徑 */
final static String PATH = "/testAuth";
final static String PATH_DEL = "/testAuth/delNode";
/** 認證類型 */
final static String authentication_type = "digest";
/** 認證正確方法 */
final static String correctAuthentication = "123456";
/** 認證錯誤方法 */
final static String badAuthentication = "654321";
static ZooKeeper zk = null;
/** 計時器 */
AtomicInteger seq = new AtomicInteger();
/** 標識 */
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;
}
// 連接狀態
KeeperState keeperState = event.getState();
// 事件類型
EventType eventType = event.getType();
// 受影響的path
String path = event.getPath();
String logPrefix = "【Watcher-" + this.seq.incrementAndGet() + "】";
System.out.println(logPrefix + "收到Watcher通知");
System.out.println(logPrefix + "連接狀態:\t" + keeperState.toString());
System.out.println(logPrefix + "事件類型:\t" + eventType.toString());
if (KeeperState.SyncConnected == keeperState) {
// 成功連接上ZK服務器
if (EventType.None == eventType) {
System.out.println(logPrefix + "成功連接上ZK服務器");
connectedSemaphore.countDown();
}
} else if (KeeperState.Disconnected == keeperState) {
System.out.println(logPrefix + "與ZK服務器斷開連接");
} else if (KeeperState.AuthFailed == keeperState) {
System.out.println(logPrefix + "權限檢查失敗");
} else if (KeeperState.Expired == keeperState) {
System.out.println(logPrefix + "會話失效");
}
System.out.println("--------------------------------------------");
}
/**
* 創建ZK連接
*
* @param connectString
* ZK服務器地址列表
* @param sessionTimeout
* Session超時時間
*/
public void createConnection(String connectString, int sessionTimeout) {
this.releaseConnection();
try {
zk = new ZooKeeper(connectString, sessionTimeout, this);
//添加節點授權
zk.addAuthInfo(authentication_type,correctAuthentication.getBytes());
System.out.println(LOG_PREFIX_OF_MAIN + "開始連接ZK服務器");
//倒數等待
connectedSemaphore.await();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 關閉ZK連接
*/
public void releaseConnection() {
if (this.zk!=null) {
try {
this.zk.close();
} catch (InterruptedException e) {
}
}
}
/**
*
* <B>方法名稱：</B>測試函數<BR>
* <B>概要說明：</B>測試認證<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("使用授權key：" + correctAuthentication + "創建節點："+ PATH + ", 初始內容是: init content");
} catch (Exception e) {
e.printStackTrace();
}
try {
zk.create(PATH_DEL, "will be deleted! ".getBytes(), acls, CreateMode.PERSISTENT);
System.out.println("使用授權key：" + correctAuthentication + "創建節點："+ PATH_DEL + ", 初始內容是: init content");
} catch (Exception e) {
e.printStackTrace();
}
// 獲取數據
getDataByNoAuthentication();
getDataByBadAuthentication();
getDataByCorrectAuthentication();
// 更新數據
updateDataByNoAuthentication();
updateDataByBadAuthentication();
updateDataByCorrectAuthentication();
// 刪除數據
deleteNodeByBadAuthentication();
deleteNodeByNoAuthentication();
deleteNodeByCorrectAuthentication();
//
Thread.sleep(1000);
deleteParent();
//釋放連接
testAuth.releaseConnection();
}
/** 獲取數據：采用錯誤的密碼 */
static void getDataByBadAuthentication() {
String prefix = "[使用錯誤的授權信息]";
try {
ZooKeeper badzk = new ZooKeeper(CONNECT_ADDR, 2000, null);
//授權
badzk.addAuthInfo(authentication_type,badAuthentication.getBytes());
Thread.sleep(2000);
System.out.println(prefix + "獲取數據：" + PATH);
System.out.println(prefix + "成功獲取數據：" + badzk.getData(PATH, false, null));
} catch (Exception e) {
System.err.println(prefix + "獲取數據失敗，原因：" + e.getMessage());
}
}
/** 獲取數據：不采用密碼 */
static void getDataByNoAuthentication() {
String prefix = "[不使用任何授權信息]";
try {
System.out.println(prefix + "獲取數據：" + PATH);
ZooKeeper nozk = new ZooKeeper(CONNECT_ADDR, 2000, null);
Thread.sleep(2000);
System.out.println(prefix + "成功獲取數據：" + nozk.getData(PATH, false, null));
} catch (Exception e) {
System.err.println(prefix + "獲取數據失敗，原因：" + e.getMessage());
}
}
/** 采用正確的密碼 */
static void getDataByCorrectAuthentication() {
String prefix = "[使用正確的授權信息]";
try {
System.out.println(prefix + "獲取數據：" + PATH);
System.out.println(prefix + "成功獲取數據：" + zk.getData(PATH, false, null));
} catch (Exception e) {
System.out.println(prefix + "獲取數據失敗，原因：" + e.getMessage());
}
}
/**
* 更新數據：不采用密碼
*/
static void updateDataByNoAuthentication() {
String prefix = "[不使用任何授權信息]";
System.out.println(prefix + "更新數據： " + 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 + "更新失敗，原因是：" + e.getMessage());
}
}
/**
* 更新數據：采用錯誤的密碼
*/
static void updateDataByBadAuthentication() {
String prefix = "[使用錯誤的授權信息]";
System.out.println(prefix + "更新數據：" + PATH);
try {
ZooKeeper badzk = new ZooKeeper(CONNECT_ADDR, 2000, null);
//授權
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 + "更新失敗，原因是：" + e.getMessage());
}
}
/**
* 更新數據：采用正確的密碼
*/
static void updateDataByCorrectAuthentication() {
String prefix = "[使用正確的授權信息]";
System.out.println(prefix + "更新數據：" + 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 + "更新失敗，原因是：" + e.getMessage());
}
}
/**
* 不使用密碼 刪除節點
*/
static void deleteNodeByNoAuthentication() throws Exception {
String prefix = "[不使用任何授權信息]";
try {
System.out.println(prefix + "刪除節點：" + 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 + "刪除成功");
}
} catch (Exception e) {
System.err.println(prefix + "刪除失敗，原因是：" + e.getMessage());
}
}
/**
* 采用錯誤的密碼刪除節點
*/
static void deleteNodeByBadAuthentication() throws Exception {
String prefix = "[使用錯誤的授權信息]";
try {
System.out.println(prefix + "刪除節點：" + PATH_DEL);
ZooKeeper badzk = new ZooKeeper(CONNECT_ADDR, 2000, null);
//授權
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 + "刪除成功");
}
} catch (Exception e) {
System.err.println(prefix + "刪除失敗，原因是：" + e.getMessage());
}
}
/**
* 使用正確的密碼刪除節點
*/
static void deleteNodeByCorrectAuthentication() throws Exception {
String prefix = "[使用正確的授權信息]";
try {
System.out.println(prefix + "刪除節點：" + PATH_DEL);
Stat stat = zk.exists(PATH_DEL, false);
if (stat!=null) {
zk.delete(PATH_DEL, -1);
System.out.println(prefix + "刪除成功");
}
} catch (Exception e) {
System.out.println(prefix + "刪除失敗，原因是：" + e.getMessage());
}
}
/**
* 使用正確的密碼刪除節點
*/
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();
}
}
}
