Zookeeper作为分布式的服务框架，虽然是java写的，但是强大的C#也可以连接使用。
C#要连接使用Zookeeper，需要借助第三方插件，而现在主要有两个插件可供使用，分别是ZooKeeperNetEx和Zookeeper.Net
Zookeeper.Net好像是是Apache官方提供的，但是5年没更新了，也就是说他依赖于.net framework，因此无法在.net core项目中使用
ZooKeeperNetEx是从java改过来的，因此里面的一些习惯是java风格的，但是好像有人在提供更新维护，支持最新的Zookeeper特性，而且摆脱了对.net framework的依赖，所以个人推荐使用ZooKeeperNetEx做开发，本文也已介绍ZooKeeperNetEx为主
新建一个控制台项目，在nuget中搜索ZooKeeperNetEx，并安装最新版
在Program的Main方法：
using org.apache.zookeeper; using org.apache.zookeeper.data; using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading; using System.Threading.Tasks; namespace AspNetCore.ZookeeperConsole { class Program { static void Main(string[] args) { //Zookeeper连接字符串，采用host:port格式，多个地址之间使用逗号（,）隔开 string connectionString = "192.168.209.133:2181,192.168.209.133:2181,192.168.209.133:2181"; //会话超时时间,单位毫秒 int sessionTimeOut = 10000; //异步监听 var watcher = new MyWatcher("ConnectWatcher"); //连接 ZooKeeper zooKeeper = new ZooKeeper(connectionString, sessionTimeOut, watcher); Thread.Sleep(1000);//停一秒，等待连接完成 while (zooKeeper.getState() == ZooKeeper.States.CONNECTING) { Console.WriteLine("等待连接完成..."); Thread.Sleep(1000); } var state = zooKeeper.getState(); if (state != ZooKeeper.States.CONNECTED && state != ZooKeeper.States.CONNECTEDREADONLY) { Console.WriteLine("连接失败：" + state); Console.ReadKey(); return; } //创建znode节点 { var data = Encoding.UTF8.GetBytes("hello world"); List<ACL> acl = ZooDefs.Ids.OPEN_ACL_UNSAFE;//创建节点时的acl权限，也可以使用下面的自定义权限 //List<ACL> acl = new List<ACL>() { // new ACL((int)ZooDefs.Perms.READ, new Id("ip", "127.0.0.1")), // new ACL((int)(ZooDefs.Perms.READ | ZooDefs.Perms.WRITE), new Id("auth", "id:pass")) //}; CreateMode createMode = CreateMode.PERSISTENT; zooKeeper.createAsync("/mynode", data, acl, createMode).Wait(); Console.WriteLine("完成创建节点"); } //节点是否存在 { var exists = zooKeeper.existsAsync("/mynode", new MyWatcher("ExistsWatcher")).GetAwaiter().GetResult(); Console.WriteLine("节点是否存在：" + exists); } //获取节点数据 { var dataResult = zooKeeper.getDataAsync("/mynode", new MyWatcher("GetWatcher")).GetAwaiter().GetResult(); var value = Encoding.UTF8.GetString(dataResult.Data); Console.WriteLine("完成读取节点：" + value); } //设置节点数据 { var data = Encoding.UTF8.GetBytes("hello world again"); zooKeeper.setDataAsync("/mynode", data); Console.WriteLine("设置节点数据"); } //重新获取节点数据 { var dataResult = zooKeeper.getDataAsync("/mynode", new MyWatcher("GetWatcher")).GetAwaiter().GetResult(); var value = Encoding.UTF8.GetString(dataResult.Data); Console.WriteLine("重新获取节点数据：" + value); } //移除节点 { zooKeeper.deleteAsync("/mynode").Wait(); Console.WriteLine("移除节点"); } Console.WriteLine("完成"); Console.ReadKey(); } } class MyWatcher : Watcher { public string Name { get; private set; } public MyWatcher(string name) { this.Name = name; } public override Task process(WatchedEvent @event) { var path = @event.getPath(); var state = @event.getState(); Console.WriteLine($"{Name} recieve: Path-{path} State-{@event.getState()} Type-{@event.get_Type()}"); return Task.FromResult(0); } } }
运行后显示结果：
这个简单的例子是使用ZooKeeperNetEx操作的简单例子，下面具体介绍
ZooKeeperNetEx连接Zookeeper只需要实例化ZooKeeper对象即可
//Zookeeper连接字符串，采用host:port格式，多个地址之间使用逗号（,）隔开 string connectionString = "192.168.209.133:2181,192.168.209.133:2181,192.168.209.133:2181"; //会话超时时间,单位毫秒 int sessionTimeOut = 10000; //异步监听 var watcher = new MyWatcher("ConnectWatcher"); //连接 ZooKeeper zooKeeper = new ZooKeeper(connectionString, sessionTimeOut, watcher);
实例化过程中至少需要三个参数
连接字符串(connectstring)：host:port形式，多个地址之间使用英文逗号隔开
会话超时时间(sessionTimeout)：当会话中，Zookeeper超过此时间未响应，则表示会话超时
监听器(watcher)：这个连接过程中可以注册一个监听器，当连接过程中出现状态改变时，会通知到监听器
ZooKeeper对象实例化过程中会异步的去连接Zookeeper，所以例子中才有一个while循环来判断状态
Thread.Sleep(1000);//停一秒，等待连接完成 while (zooKeeper.getState() == ZooKeeper.States.CONNECTING) { Console.WriteLine("等待连接完成..."); Thread.Sleep(1000); }
而Zookeeper的连接状态有6种：
//ZooKeeper.States的枚举
CONNECTING = 0, //连接中 CONNECTED = 1, //已连接 CONNECTEDREADONLY = 2, //已连接，但是只能只读访问 CLOSED = 3, //已关闭连接 AUTH_FAILED = 4, //认证失败 NOT_CONNECTED = 5 //未连接
当应用连接到Zookeeper时，一般都是读取数据，所以主需要只读连接就可以满足的，不过具体还是要看需求。
当在指定的会话时间内未成功连接时，则会导致连接超时，因为这个过程是异步的，所以需要一个监听器来接收。
监听器其实是org.apache.zookeeper.Watcher的一个子类，这个需要开发者去继承实现它的process方法，比如上面的例子中我们就简单的实现
class MyWatcher : Watcher { public string Name { get; private set; } public MyWatcher(string name) { this.Name = name; } public override Task process(WatchedEvent @event) { var path = @event.getPath(); var state = @event.getState(); Console.WriteLine($"{Name} recieve: Path-{path} State-{@event.getState()} Type-{@event.get_Type()}"); return Task.FromResult(0); } }
这里仅仅只是简单的输出节点路径、监听事件响应状态和监听事件类型
//监听事件响应状态，Watcher.Event.KeeperState的枚举 Expired = -112, //连接超时 Disconnected = 0, //连接断开 SyncConnected = 3, //已同步连接 AuthFailed = 4, //认证失败 ConnectedReadOnly = 5 //只读连接 //监听事件类型，Watcher.Event.EventType的枚举 None = -1, //非节点操作事件 NodeCreated = 1, //创建节点事件 NodeDeleted = 2, //删除节点事件 NodeDataChanged = 3, //节点数据改变 NodeChildrenChanged = 4 //子节点发生改变
为什么要有监听器？监听器就类似一个回调，当发生某个事件时，我们的应用可能需要进行相应的处理，如当连接断开时，由于监听器的存在，我们可以让我们的应用程序重新与Zookeeper建立连接。
ZooKeeperNetEx创建znode节点使用的是createAsync异步方法，传入4个参数，分别是
节点路径(path):：创建的节点路径
节点数据(data)：节点数据，它是一个字节数组，可以通过编码将字符串转化为字符数组
ACL权限(acl)：ACL权限，可以使用已定义好的，也可以使用自定义，如：
//已经定义好的，ZooDefs.Ids的枚举 OPEN_ACL_UNSAFE：完全开放 CREATOR_ALL_ACL：创建该znode的连接拥有所有权限 READ_ACL_UNSAFE：所有的客户端都可读
自定义方式如：
List<ACL> acl = new List<ACL>() { new ACL((int)ZooDefs.Perms.READ, new Id("ip", "127.0.0.1")), new ACL((int)(ZooDefs.Perms.READ | ZooDefs.Perms.WRITE), new Id("auth", "id:pass")) };
节点类型(createMode)：节点类型有4种，分别是CreateMode类的4个静态字段
PERSISTENT：持久化节点
PERSISTENT_SEQUENTIAL：持久化有序节点
EPHEMERAL：临时节点（连接断开自动删除）
EPHEMERAL_SEQUENTIAL：临时有序节点（连接断开自动删除）
createAsync异步方法会返回实际创建的znode路径，貌似没什么用（在创建顺序节点时会用到，当一个新的znode被创建为一个顺序节点时，ZooKeeper通过将10位的序列号附加到原始名称来设置znode的路径）
上面这个是ZooKeeperNetEx创建znode节点的方法，而对znode的其他操作的参数就很简单了，这里就不在重述，需要具体操作才能理解，一个简单的介绍如下：
//删除znode节点 public Task deleteAsync(string path, int version = -1); //指定的znode节点是否存在 public Task<Stat> existsAsync(string path, Watcher watcher); public Task<Stat> existsAsync(string path, bool watch = false); //获取znode节点数据 public Task<DataResult> getDataAsync(string path, bool watch = false); public Task<DataResult> getDataAsync(string path, Watcher watcher); //设置指定znode节点的数据 public Task<Stat> setDataAsync(string path, byte[] data, int version = -1); //获取指定znode节点的子节点，注意，监听器是注册给当前节点的，而非子节点 public Task<ChildrenResult> getChildrenAsync(string path, Watcher watcher); public Task<ChildrenResult> getChildrenAsync(string path, bool watch = false);
可以比较一下上一节介绍的zkCli对znode节点的操作就很容易理解了。
另外，需要注意的是，existsAsync方法、getDataAsync方法和getChildrenAsync方法可以在指定的znode注册一个监听器，setDataAsync方法却没有这个注册功能，这个是因为Zookeeper注册的监听器只会响应一次，当需要再次响应时，需要重新注册，这时就可以调用existsAsync方法或者getDataAsync方法或者getChildrenAsync方法进行重新注册了！
上一节说到ACL权限不仅可以在创建是给予，在创建后也可以修改，ZookeeperNetEx操作znode的ACL权限使用的方法如下：
//获取ACL权限 public Task<ACLResult> getACLAsync(string path); //设置ACL权限 public Task<Stat> setACLAsync(string path, List<ACL> acl, int aclVersion = -1);
说到ACL，自然就会认证存在，ZookeeperNetEx添加认证使用的是addAuthInfo方法
public void addAuthInfo(string scheme, byte[] auth);
其中scheme就是我们上一节介绍的那几种：
world：默认模式，所有客户端都拥有指定的权限。world下只有一个id选项，就是anyone，通常组合写法为world:anyone:[permissons]； auth：只有经过认证的用户才拥有指定的权限。通常组合写法为auth:user:password:[permissons]，使用这种模式时，你需要先进行登录，之后采用auth模式设置权限时，user和password都将使用登录的用户名和密码；比如： digest：只有经过认证的用户才拥有指定的权限。通常组合写法为digest:user:BASE64(SHA1(password)):[permissons]，这种形式下的密码必须通过SHA1和BASE64进行双重加密； ip：限制只有特定IP的客户端才拥有指定的权限。通常组成写法为ip:182.168.0.168:[permissions]； super：代表超级管理员，拥有所有的权限，需要修改Zookeeper启动脚本进行配置。
auth是认证数据，如果没有则可以是空的字节数组，如：
//world模式认证 zk.addAuthInfo("world",new byte[0]); //auth模式认证 byte[] auth=Encoding.UTF8.GetBytes("id:pass") zk.addAuthInfo("auth",new byte[0]); //digest模式认证 byte[] auth=Encoding.UTF8.GetBytes("加密后的字符串") zk.addAuthInfo("digest",new byte[0]);
ZookeeperNetEx关闭会话使用的是closeAsync方法，调用这个方法之后，当前连接对象ZooKeeper就不能再访问了
public Task closeAsync();
其他常用方法就不介绍了，一般时候基本上也用不上。
简单封装
真实项目中，我们连接Zookeeper多数只是为了创建znode节点，读取数据等等操作，一般不会去设置ACL等权限，甚至连认证都可能不会用到，为了更好使用ZookeeperNetEx，我做了一层简单的封装，用以满足常见的CRUD操作，同时也让它更符合我们.net开发的一些习惯。
using org.apache.zookeeper; using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Threading.Tasks; using System.Collections.Concurrent; using System.Threading; using System.Text; using org.apache.zookeeper.data; using org.apache.utils; using System.Diagnostics; namespace AspNetCore.ZookeeperConsole { /// <summary> /// Zookeeper辅助类 /// </summary> public class ZookeeperHelper : Watcher, IDisposable { /// <summary> /// Zookeeper路径分隔符 /// </summary> string sep = "/"; /// <summary> /// Zookeeper访问对象 /// </summary> ZooKeeper zookeeper; /// <summary> /// Zookeeper集群地址 /// </summary> string[] address; /// <summary> /// 路径监控节点列表 /// </summary> ConcurrentDictionary<string, NodeWatcher> nodeWatchers = new ConcurrentDictionary<string, NodeWatcher>(); /// <summary> /// 节点的默认权限 /// </summary> List<ACL> defaultACL = ZooDefs.Ids.OPEN_ACL_UNSAFE; /// <summary> /// 默认的监听器 /// </summary> DefaultWatcher defaultWatcher; /// <summary> /// 监控定时器 /// </summary> System.Timers.Timer timer; /// <summary> /// 同步锁 /// </summary> AutoResetEvent are = new AutoResetEvent(false); /// <summary> /// 是否正常关闭 /// </summary> bool isClose = false; /// <summary> /// 回话超时时间 /// </summary> public int SessionTimeout { get; set; } = 10000; /// <summary> /// 当前路径 /// </summary> public string CurrentPath { get; private set; } /// <summary> /// 是否已连接Zookeeper /// </summary> public bool Connected { get { return zookeeper != null && (zookeeper.getState() == ZooKeeper.States.CONNECTED || zookeeper.getState() == ZooKeeper.States.CONNECTEDREADONLY); } } /// <summary> /// Zookeeper是否有写的权限 /// </summary> public bool CanWrite { get { return zookeeper != null && zookeeper.getState() == ZooKeeper.States.CONNECTED; } } /// <summary> /// 数据编码 /// </summary> public Encoding Encoding { get; set; } = Encoding.Default; /// <summary> /// 释放时发生 /// </summary> public event Action OnDisposing; /// <summary> /// 在重新连接时发生 /// </summary> public event Action OnConnected; /// <summary> /// 构造函数 /// </summary> /// <param name="address">集群地址(host:prot)</param> public ZookeeperHelper(params string[] address) : this(address, "") { } /// <summary> /// 构造函数 /// </summary> /// <param name="address">集群地址(host:prot)</param> /// <param name="root">初始化根路经</param> public ZookeeperHelper(string[] address, string root) { this.address = address.ToArray(); CurrentPath = string.IsNullOrWhiteSpace(root) ? sep : root; SetLogger(new ZookeeperLogger()); timer = new System.Timers.Timer(); timer.Interval = 5000; timer.Elapsed += Timer_Elapsed; } /// <summary> /// Zookeeper的日志设置 /// </summary> /// <param name="log"></param> public static void SetLogger(ZookeeperLogger log) { ZooKeeper.LogLevel = log.LogLevel; ZooKeeper.LogToFile = log.LogToFile; ZooKeeper.LogToTrace = log.LogToTrace; ZooKeeper.CustomLogConsumer = log; } #region 私有方法 /// <summary> /// 定时器 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void Timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e) { timer.Enabled = false; if (Monitor.TryEnter(timer))//每次只能一个线程进去 { if (!isClose) { //Thread.Sleep(SessionTimeout); if (!Connected) { try { zookeeper?.closeAsync(); are.Reset(); zookeeper = new ZooKeeper(string.Join(",", address), SessionTimeout, defaultWatcher); if (are.WaitOne(SessionTimeout) && Connected)//会话未超时，表示成功连接 { //挂载监听器 foreach (var key in nodeWatchers.Keys) { NodeWatcher watcher; if (nodeWatchers.TryGetValue(key, out watcher)) { WatchAsync(key, watcher, true).Wait(); } } OnConnected?.Invoke(); Monitor.Exit(timer); return; } } catch { } timer.Enabled = true; } } Monitor.Exit(timer); } } /// <summary> /// 检查连接是否正常 /// </summary> private void CheckConnection() { if (!Connected) { throw new Exception("fail to connect to the server:" + string.Join(",", address)); } } /// <summary> /// 检查是否具有写的权限 /// </summary> private void CheckWriten() { if (!CanWrite) { throw new Exception("this connection is in readonly mode"); } } /// <summary> /// 连接数据成Zookeeper的路径格式 /// </summary> /// <param name="paths">路径</param> /// <returns>连接后的路径</returns> private string Combine(params string[] paths) { List<string> list = new List<string>(); foreach (var path in paths) { var ps = path.Split(new string[] { "/", "\" }, StringSplitOptions.RemoveEmptyEntries); foreach (var p in ps) { if (p == ".")//当前路径 { continue; } else if (p == "..")//回退 { if (list.Count == 0) { throw new ArgumentOutOfRangeException("path is out of range"); } list.RemoveAt(list.Count - 1); } else { list.Add(p); } } } return sep + string.Join(sep, list.ToArray()); } /// <summary> /// 使用指定的分隔符连接路径 /// </summary> /// <param name="sep">分隔符</param> /// <param name="paths">路径</param> /// <returns>连接后的路径</returns> private string MakePathName(string sep, params string[] paths) { List<string> list = new List<string>(); foreach (var path in paths) { var ps = path.Split(new string[] { "/", "\" }, StringSplitOptions.RemoveEmptyEntries); list.AddRange(ps); } return string.Join(sep, list.ToArray()); } /// <summary> /// 获取绝对路径 /// </summary> /// <param name="path">路径</param> /// <param name="isAbsolute">路径是否是绝对路径</param> /// <returns>绝对路径</returns> private string GetAbsolutePath(string path, bool isAbsolute) { if (!isAbsolute) { path = Combine(CurrentPath, path); } else { path = Combine(path); } return path; } #endregion /// <summary> /// 连接Zookeeper /// </summary> /// <returns>成功连接返回true,否则返回false</returns> public bool Connect() { if (Connected) { return true; } if (zookeeper == null) { lock (this) { defaultWatcher = defaultWatcher ?? new DefaultWatcher(this, are); are.Reset(); zookeeper = new ZooKeeper(string.Join(",", address), SessionTimeout, defaultWatcher); are.WaitOne(SessionTimeout); } } if (!Connected) { return false; } OnConnected?.Invoke(); return true; } /// <summary> /// 关闭连接 /// </summary> public void Close() { isClose = true; if (Connected) { zookeeper.closeAsync().Wait(); } } /// <summary> /// 监控回调 /// </summary> /// <param name="event">回调事件</param> /// <returns>异步</returns> public async override Task process(WatchedEvent @event) { ZookeeperEvent ze = new ZookeeperEvent(@event); if (!string.IsNullOrEmpty(ze.Path)) { NodeWatcher watcher; if (nodeWatchers.TryGetValue(ze.Path, out watcher)) { if (watcher != null) { try { watcher.Process(ze); } catch { } await WatchAsync(ze.Path, watcher, true);//重新监控 } } } } /// <summary> /// 修改当前目录地址 /// </summary> /// <param name="path"></param> public void ChangeDirectory(string path) { this.CurrentPath = Combine(path); } /// <summary> /// 切换到相对目录下 /// </summary> /// <param name="path"></param> public void Goto(string path) { this.CurrentPath = Combine(this.CurrentPath, path); } /// <summary> /// 使用认证 /// </summary> /// <param name="scheme">认证类型</param> /// <param name="auth">认证数据</param> public void Authorize(AuthScheme scheme, string auth = "") { CheckConnection(); zookeeper.addAuthInfo(scheme.ToString().ToLower(), Encoding.GetBytes(auth)); } #region 监听与取消 /// <summary> /// 对当前路径添加监控 /// </summary> /// <param name="delegate">监控</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAsync(WatcherEvent @delegate) { return await WatchAsync(CurrentPath, @delegate, true); } /// <summary> /// 对当前路径添加监控 /// </summary> /// <param name="watcher">监控</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAsync(NodeWatcher watcher) { return await WatchAsync(CurrentPath, watcher, true); } /// <summary> /// 对指定路径添加监控 /// </summary> /// <param name="path">节点路径</param> /// <param name="delegate">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAsync(string path, WatcherEvent @delegate, bool isAbsolutePath = false) { var array = await WatchManyAsync(new string[] { path }, @delegate, isAbsolutePath); return array.FirstOrDefault(); } /// <summary> /// 对指定路径添加监控 /// </summary> /// <param name="path">节点路径</param> /// <param name="watcher">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAsync(string path, NodeWatcher watcher, bool isAbsolutePath = false) { var array = await WatchManyAsync(new string[] { path }, watcher, isAbsolutePath); return array.FirstOrDefault(); } /// <summary> /// 监控多个路径，但是不包括子路径 /// </summary> /// <param name="paths">节点路径</param> /// <param name="delegate">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool[]> WatchManyAsync(string[] paths, WatcherEvent @delegate, bool isAbsolutePath = false) { var watcher = new NodeWatcher(); watcher.AllTypeChanged += @delegate; return await WatchManyAsync(paths, watcher, isAbsolutePath); } /// <summary> /// 监控多个路径，但是不包括子路径 /// </summary> /// <param name="paths">节点路径</param> /// <param name="watcher">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool[]> WatchManyAsync(string[] paths, NodeWatcher watcher, bool isAbsolutePath = false) { CheckConnection(); List<bool> list = new List<bool>(); foreach (var path in paths) { try { var p = GetAbsolutePath(path, isAbsolutePath); if (await zookeeper.existsAsync(p, this) != null) { nodeWatchers[p] = watcher; list.Add(true); } else { nodeWatchers.TryRemove(p, out _); list.Add(false); } } catch { list.Add(false); } } return list.ToArray(); } /// <summary> /// 监控当前路径，包括子路径 /// </summary> /// <param name="delegate">监控</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAllAsync(WatcherEvent @delegate) { return await WatchAllAsync(CurrentPath, @delegate, true); } /// <summary> /// 监控当前路径，包括子路径 /// </summary> /// <param name="watcher">监控</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAllAsync(NodeWatcher watcher) { return await WatchAllAsync(CurrentPath, watcher, true); } /// <summary> /// 监控指定路径，包括子路径 /// </summary> /// <param name="path">节点路径</param> /// <param name="delegate">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAllAsync(string path, WatcherEvent @delegate, bool isAbsolutePath = false) { var array = await WatchAllAsync(new string[] { path }, @delegate, isAbsolutePath); return array.FirstOrDefault(); } /// <summary> /// 监控指定路径，包括子路径 /// </summary> /// <param name="path">节点路径</param> /// <param name="watcher">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool> WatchAllAsync(string path, NodeWatcher watcher, bool isAbsolutePath = false) { var array = await WatchAllAsync(new string[] { path }, watcher, isAbsolutePath); return array.FirstOrDefault(); } /// <summary> /// 监控所有路径，包括子路径 /// </summary> /// <param name="paths">节点路径</param> /// <param name="delegate">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool[]> WatchAllAsync(string[] paths, WatcherEvent @delegate, bool isAbsolutePath = false) { var watcher = new NodeWatcher(); watcher.AllTypeChanged += @delegate; return await WatchAllAsync(paths, watcher, isAbsolutePath); } /// <summary> /// 监控所有路径，包括子路径 /// </summary> /// <param name="paths">节点路径</param> /// <param name="watcher">监控</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步，true表示成功，false表示失败</returns> public async Task<bool[]> WatchAllAsync(string[] paths, NodeWatcher watcher, bool isAbsolutePath = false) { CheckConnection(); List<bool> list = new List<bool>(); foreach (var path in paths) { try { var p = GetAbsolutePath(path, isAbsolutePath); if (await zookeeper.existsAsync(p, this) != null) { nodeWatchers[p] = watcher; list.Add(true); var result = await zookeeper.getChildrenAsync(p); await WatchAllAsync(result.Children.Select(c => Combine(p, c)).ToArray(), watcher, true); } else { nodeWatchers.TryRemove(p, out _); list.Add(false); } } catch { list.Add(false); } } return list.ToArray(); } /// <summary> /// 取消多个指定路径上的监控 /// </summary> /// <param name="path">节点路径</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步</returns> public async Task CancelAsync(string path, bool isAbsolutePath = true) { await CancelAsync(new string[] { path }, isAbsolutePath); } /// <summary> /// 取消多个指定路径上的监控 /// </summary> /// <param name="path">节点路径</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>异步</returns> public async Task CancelAsync(string[] paths, bool isAbsolutePath = true) { foreach (var path in paths) { var p = GetAbsolutePath(path, isAbsolutePath); nodeWatchers.TryRemove(p, out _); await Task.CompletedTask; } } /// <summary> /// 获取指定路径上的监控 /// </summary> /// <param name="path">节点路径</param> /// <param name="isAbsolutePath">是否绝对路径</param> /// <returns>存在则返回监控对象，否则返回null</returns> public NodeWatcher GetWatcher(string path, bool isAbsolutePath = true) { path = GetAbsolutePath(path, isAbsolutePath); NodeWatcher watcher; if (nodeWatchers.TryGetValue(path, out watcher)) { return watcher; } return null; } #endregion #region 基本数据操作 /// <summary> /// 当前节点是否存在 /// </summary> /// <returns>存在返回true，否则返回false</returns> public bool Exists() { return ExistsAsync().GetAwaiter().GetResult(); } /// <summary> /// 指定节点是否存在（相对当前节点） /// </summary> /// <param name="path">节点路径</param> /// <returns>存在返回true，否则返回false</returns> public bool Exists(string path) { return ExistsAsync(path).GetAwaiter().GetResult(); } /// <summary> /// 指定节点是否存在 /// </summary> /// <param name="absolutePath">绝对路径</param> /// <returns>存在返回true，否则返回false</returns> public bool ExistsByAbsolutePath(string absolutePath) { return ExistsByAbsolutePathAsync(absolutePath).GetAwaiter().GetResult(); } /// <summary> /// 当前节点是否存在 /// </summary> /// <returns>异步，存在返回true，否则返回false</returns> public async Task<bool> ExistsAsync() { return await ExistsByAbsolutePathAsync(CurrentPath); } /// <summary> /// 指定节点是否存在（相对当前节点） /// </summary> /// <param name="path">节点路径</param> /// <returns>异步，存在返回true，否则返回false</returns> public async Task<bool> ExistsAsync(string path) { path = Combine(CurrentPath, path); return await ExistsByAbsolutePathAsync(path); } /// <summary> /// 指定节点是否存在 /// </summary> /// <param name="absolutePath">绝对路径</param> /// <returns>异步，存在返回true，否则返回false</returns> public async Task<bool> ExistsByAbsolutePathAsync(string absolutePath) { absolutePath = Combine(absolutePath); return await zookeeper.existsAsync(absolutePath, false) != null; } /// <summary> /// 添加或者修改当前路径上的数据 /// </summary> /// <param name="value">数据</param> /// <param name="persistent">是否持久节点</param> /// <param name="sequential">是否顺序节点</param> /// <returns>znode节点名，不包含父节点路径</returns> public string SetData(string value, bool persistent = false, bool sequential = false) { return SetDataAsync(value, persistent, sequential).GetAwaiter().GetResult(); } /// <summary> /// 添加或者修改指定相对路径上的数据 /// </summary> /// <param name="path">相对路径</param> /// <param name="value">数据</param> /// <param name="persistent">是否持久节点</param> /// <param name="sequential">是否顺序节点</param> /// <returns>znode节点名，不包含父节点路径</returns> public string SetData(string path, string value, bool persistent = false, bool sequential = false) { return SetDataAsync(path, value, persistent, sequential).GetAwaiter().GetResult(); } /// <summary> /// 添加或者修改指定绝对路径上的数据 /// </summary> /// <param name="absolutePath">绝对路径</param> /// <param name="value">数据</param> /// <param name="persistent">是否持久节点</param> /// <param name="sequential">是否顺序节点</param> /// <returns>znode节点名，不包含父节点路径</returns> public string SetDataByAbsolutePath(string absolutePath, string value, bool persistent = false, bool sequential = false) { return SetDataByAbsolutePathAsync(absolutePath, value, persistent, sequential).GetAwaiter().GetResult(); } /// <summary> /// 添加或者修改当前路径上的数据 /// </summary> /// <param name="value">数据</param> /// <param name="persistent">是否持久节点</param> /// <param name="sequential">是否顺序节点</param> /// <returns>znode节点名，不包含父节点路径</returns> public async Task<string> SetDataAsync(string value, bool persistent = false, bool sequential = false) { return await SetDataByAbsolutePathAsync(CurrentPath, value, persistent, sequential); } /// <summary> /// 添加或者修改指定相对路径上的数据 /// </summary> /// <param name="path">相对路径</param> /// <param name="value">数据</param> /// <param name="persistent">是否持久节点</param> /// <param name="sequential">是否顺序节点</param> /// <returns>znode节点名，不包含父节点路径</returns> public async Task<string> SetDataAsync(string path, string value, bool persistent = false, bool sequential = false) { path = Combine(CurrentPath, path); return await SetDataByAbsolutePathAsync(path, value, persistent, sequential); } /// <summary> /// 添加或者修改指定绝对路径上的数据 /// </summary> /// <param name="absolutePath">绝对路径</param> /// <param name="value">数据</param> /// <param name="persistent">是否持久节点</param> /// <param name="sequential">是否顺序节点</param> /// <returns>znode节点名，不包含父节点路径</returns> public async Task<string> SetDataByAbsolutePathAsync(string absolutePath, string value, bool persistent = false, bool sequential = false) { CheckConnection(); CheckWriten(); absolutePath = Combine(absolutePath); if (await zookeeper.existsAsync(absolutePath, false) == null) { absolutePath = await zookeeper.createAsync(absolutePath, Encoding.GetBytes(value), defaultACL, persistent ? sequential ? CreateMode.PERSISTENT_SEQUENTIAL : CreateMode.PERSISTENT : sequential ? CreateMode.EPHEMERAL_SEQUENTIAL : CreateMode.EPHEMERAL); } else { await zookeeper.setDataAsync(absolutePath, Encoding.GetBytes(value)); } return absolutePath.Split(new string[] { sep }, StringSplitOptions.RemoveEmptyEntries).LastOrDefault(); } /// <summary> /// 获取指定相对路径上的数据 /// </summary> /// <param name="path">相对路径</param> /// <returns>相对路径上的数据</returns> public string GetData(string path) { return GetDataAsync(path).GetAwaiter().GetResult(); } /// <summary> /// 获取指定绝对路径上的数据 /// </summary> /// <param name="absolutePath">绝对路径</param> /// <returns>相对路径上的数据</returns> public string GetDataByAbsolutePath(string absolutePath) { return GetDataByAbsolutePathAsync(absolutePath).GetAwaiter().GetResult(); } /// <summary> /// 获取指定相对路径上的数据 /// </summary> /// <param name="path">相对路径</param> /// <returns>相对路径上的数据</returns> public async Task<string> GetDataAsync(string path) { path = Combine(CurrentPath, path); return await GetDataByAbsolutePathAsync(path); } /// <summary> /// 获取指定绝对路径上的数据 /// </summary> /// <param name="absolutePath">绝对路径</param> /// <returns>绝对路径上的数据</returns> public async Task<string> GetDataByAbsolutePathAsync(string absolutePath) { CheckConnection(); absolutePath = Combine(absolutePath); if (await zookeeper.existsAsync(absolutePath, false) == null) { return ""; } var data = await zookeeper.getDataAsync(absolutePath, false); return Encoding.GetString(data.Data); } /// <summary> /// 获取指定节点及其字节点的所有值，使用路径做键返回字典型 /// </summary> /// <param name="sep"></param> /// <returns></returns> public async Task<IDictionary<string, string>> GetDictionaryAsync(string sep = ":") { CheckConnection(); Dictionary<string, string> dict = new Dictionary<string, string>(); async Task action(string path) { try { var result = await zookeeper.getChildrenAsync(path, false); string name = MakePathName(sep, path); dict[name] = await GetDataByAbsolutePathAsync(path); foreach (var child in result.Children) { var p = Combine(path, child); await action(p); } } catch (Exception ex) { } } await action(CurrentPath); return dict; } /// <summary> /// 获取子节点 /// </summary> /// <param name="path">相对路径</param> /// <param name="order">是否按时间排序</param> /// <returns>子节点数组（节点路径不含父节点路径）</returns> public async Task<string[]> GetChildrenAsync(string path, bool order = false) { path = Combine(CurrentPath, path); return await GetChildrenByAbsolutePathAsync(path, order); } /// <summary> /// 获取指定路径绝对路径下的子节点 /// </summary> /// <param name="absolutePath">绝对路径</param> /// <param name="order">是否按时间排序</param> /// <returns>子节点数组（节点路径不含父节点路径）</returns> public async Task<string[]> GetChildrenByAbsolutePathAsync(string absolutePath, bool order = false) { var result = await zookeeper.getChildrenAsync(absolutePath, false); if (!order) { return result.Children.ToArray(); } List<(string, long)> list = new List<(string, long)>(); foreach (var child in result.Children) { var p = Combine(absolutePath, child); var stat = await zookeeper.existsAsync(p, false); if (stat != null) { list.Add((child, stat.getCtime())); } } return list.OrderBy(l => l.Item2).Select(l => l.Item1).ToArray(); } /// <summary> /// 移除当前路径节点 /// </summary> public void Delete() { DeleteAsync().Wait(); } /// <summary> /// 移除相对当前的指定路径节点及子节点 /// </summary> /// <param name="path">相对路径</param> public void Delete(string path) { DeleteAsync(path).Wait(); } /// <summary> /// 移除指定绝对路径节点及子节点 /// </summary> /// <param name="absolutePath">绝对路径</param> public void DeleteByAbsolutePath(string absolutePath) { DeleteByAbsolutePathAsync(absolutePath).Wait(); } /// <summary> /// 移除当前路径节点 /// </summary> public async Task DeleteAsync() { await DeleteByAbsolutePathAsync(CurrentPath); } /// <summary> /// 移除相对当前的指定路径节点及子节点 /// </summary> /// <param name="path">相对路径</param> public async Task DeleteAsync(string path) { path = Combine(CurrentPath, path); await DeleteByAbsolutePathAsync(path); } /// <summary> /// 移除指定绝对路径节点及子节点 /// </summary> /// <param name="absolutePath">绝对路径</param> public async Task DeleteByAbsolutePathAsync(string absolutePath) { if (await ExistsByAbsolutePathAsync(absolutePath)) { var children = await GetChildrenByAbsolutePathAsync(absolutePath); foreach (var child in children) { var path = Combine(absolutePath, child); await DeleteByAbsolutePathAsync(path); } absolutePath = Combine(absolutePath); await zookeeper.deleteAsync(absolutePath); } } #endregion /// <summary> /// 释放资源 /// </summary> public void Dispose() { OnDisposing?.Invoke(); Close(); timer?.Dispose(); nodeWatchers?.Clear(); are?.Dispose(); GC.Collect(); } /// <summary> /// 默认的监听器，用于初始化使用 /// </summary> public class DefaultWatcher : Watcher { /// <summary> /// waithandle同步 /// </summary> EventWaitHandle ewh; /// <summary> /// 辅助类 /// </summary> ZookeeperHelper zookeeperHelper; public DefaultWatcher(ZookeeperHelper zookeeperHelper, EventWaitHandle ewh) { this.ewh = ewh; this.zookeeperHelper = zookeeperHelper; } /// <summary> /// 回调 /// </summary> /// <param name="event">监听事件对象</param> /// <returns></returns> public override Task process(WatchedEvent @event) { var state = @event.getState(); if (state == Event.KeeperState.ConnectedReadOnly || state == Event.KeeperState.SyncConnected)//连接时 { ewh.Set(); } else if ((state == Event.KeeperState.Expired) && !zookeeperHelper.isClose)//回话过期重新建立连接 { zookeeperHelper.timer.Enabled = true; } return Task.FromResult(1); } } } /// <summary> /// 认证类型 /// </summary> public enum AuthScheme { /// <summary> /// 下面只有一个id，叫anyone，world:anyone代表任何人，zookeeper中对所有人有权限的结点就是属于world:anyone类型的。创建节点的默认权限。有唯一的id是anyone授权的时候的模式为 world:anyone:rwadc 表示所有人都对这个节点有rwadc的权限 /// </summary> World = 0, /// <summary> ///不需要id,只要是通过authentication的user都有权限（zookeeper支持通过kerberos来进行authencation, 也支持username/password形式的authentication) /// </summary> Auth = 1, /// <summary> /// 它对应的id为username:BASE64(SHA1(password))，它需要先通过加密过的username:password形式的authentication。 /// </summary> Digest = 2, /// <summary> ///它对应的id为客户机的IP地址，设置的时候可以设置一个ip段，比如ip:192.168.1.0/16。 /// </summary> Ip = 3, /// <summary> /// 在这种scheme情况下，对应的id拥有超级权限，可以做任何事情(cdrwa） /// </summary> Super = 4 } /// <summary> /// Zookeeper事件数据 /// </summary> public class ZookeeperEvent { public ZookeeperEvent(WatchedEvent @event) { switch (@event.getState()) { case Watcher.Event.KeeperState.AuthFailed: State = EventState.AuthFailed; break; case Watcher.Event.KeeperState.ConnectedReadOnly: State = EventState.ConnectedReadOnly; break; case Watcher.Event.KeeperState.Disconnected: State = EventState.Disconnected; break; case Watcher.Event.KeeperState.Expired: State = EventState.Expired; break; case Watcher.Event.KeeperState.SyncConnected: State = EventState.SyncConnected; break; } switch (@event.get_Type()) { case Watcher.Event.EventType.NodeChildrenChanged: Type = EventType.NodeChildrenChanged; break; case Watcher.Event.EventType.NodeCreated: Type = EventType.NodeCreated; break; case Watcher.Event.EventType.NodeDataChanged: Type = EventType.NodeDataChanged; break; case Watcher.Event.EventType.NodeDeleted: Type = EventType.NodeDeleted; break; case Watcher.Event.EventType.None: Type = EventType.None; break; } Path = @event.getPath(); } /// <summary> /// 当前连接状态 /// </summary> public EventState State { get; private set; } /// <summary> /// 事件类型 /// </summary> public EventType Type { get; private set; } /// <summary> /// 事件路径 /// </summary> public string Path { get; private set; } /// <summary> /// 连接状态 /// </summary> public enum EventState {/// <summary> /// 超时 /// </summary> Expired = -112, /// <summary> /// 连接已断开 /// </summary> Disconnected = 0, /// <summary> /// 已建立连接 /// </summary> SyncConnected = 3, /// <summary> /// 认证失败 /// </summary> AuthFailed = 4, /// <summary> /// 已建立连接，但是只支持只读模式 /// </summary> ConnectedReadOnly = 5 } /// <summary> /// 时间类型 /// </summary> public enum EventType { /// <summary> /// 空类型，如：建立连接时 /// </summary> None = -1, /// <summary> /// 节点创建时 /// </summary> NodeCreated = 1, /// <summary> /// 节点删除时 /// </summary> NodeDeleted = 2, /// <summary> /// 节点数据改变时 /// </summary> NodeDataChanged = 3, /// <summary> /// 节点增加子节点时 /// </summary> NodeChildrenChanged = 4 } } /// <summary> /// 监控对象 /// </summary> public class NodeWatcher { /// <summary> /// 节点创建时调用事件 /// </summary> public event WatcherEvent NodeCreated; /// <summary> /// 节点删除时调用事件 /// </summary> public event WatcherEvent NodeDeleted; /// <summary> /// 节点数据改变时调用事件 /// </summary> public event WatcherEvent NodeDataChanged; /// <summary> /// 节点增加子节点时调用事件 /// </summary> public event WatcherEvent NodeChildrenChanged; /// <summary> /// 不区分类型，所有的类型都会调用 /// </summary> public event WatcherEvent AllTypeChanged; /// <summary> /// 触发，执行事件 /// </summary> /// <param name="event"></param> public void Process(ZookeeperEvent @event) { try { switch (@event.Type) { case ZookeeperEvent.EventType.NodeChildrenChanged: NodeChildrenChanged?.Invoke(@event); break; case ZookeeperEvent.EventType.NodeCreated: NodeCreated?.Invoke(@event); break; case ZookeeperEvent.EventType.NodeDeleted: NodeDeleted?.Invoke(@event); break; case ZookeeperEvent.EventType.NodeDataChanged: NodeDataChanged?.Invoke(@event); break; } AllTypeChanged?.Invoke(@event); } catch { } } } /// <summary> /// 监控事件委托 /// </summary> /// <param name="event"></param> public delegate void WatcherEvent(ZookeeperEvent @event); /// <summary> /// Zookeeper默认日志记录 /// </summary> public class ZookeeperLogger : ILogConsumer { /// <summary> /// 是否记录日志到文件 /// </summary> public bool LogToFile { get; set; } = false; /// <summary> /// 是否记录堆栈信息 /// </summary> public bool LogToTrace { get; set; } = true; /// <summary> /// 日志级别 /// </summary> public TraceLevel LogLevel { get; set; } = TraceLevel.Warning; /// <summary> /// 日志记录 /// </summary> /// <param name="severity"></param> /// <param name="className"></param> /// <param name="message"></param> /// <param name="exception"></param> public virtual void Log(TraceLevel severity, string className, string message, Exception exception) { Console.WriteLine(string.Format("Level:{0} className:{1} message:{2}", severity, className, message)); Console.WriteLine(exception.StackTrace); } } }
简单的使用例子：
using System; using System.Collections.Generic; using System.Text; using System.Threading; namespace AspNetCore.ZookeeperConsole { class Program { static void Main(string[] args) { //Zookeeper连接字符串，采用host:port格式，多个地址之间使用逗号（,）隔开 string[] address = new string[] { "192.168.209.133:2181", "192.168.209.133:2181", "192.168.209.133:2181" }; //会话超时时间,单位毫秒 int sessionTimeOut = 10000; ZookeeperHelper zookeeperHelper = new ZookeeperHelper(address, "/"); zookeeperHelper.SessionTimeout = sessionTimeOut; zookeeperHelper.Connect();//发起连接 while (!zookeeperHelper.Connected) { Thread.Sleep(1000); //停一秒，等待连接完成 } //创建znode节点 { zookeeperHelper.SetData("/mynode", "hello world", true, false); Console.WriteLine("完成创建节点"); } //节点是否存在 { var exists = zookeeperHelper.Exists("/mynode"); Console.WriteLine("节点是否存在：" + exists); } //添加监听器 { zookeeperHelper.WatchAsync("/mynode", (e) => { Console.WriteLine($"recieve: Path-{e.Path} State-{e.State} Type-{e.Type}"); }).Wait(); } //获取节点数据 { var value = zookeeperHelper.GetData("/mynode"); Console.WriteLine("完成读取节点：" + value); } //设置节点数据 { zookeeperHelper.SetData("/mynode", "hello world again"); Console.WriteLine("设置节点数据"); } //重新获取节点数据 { var value = zookeeperHelper.GetData("/mynode"); Console.WriteLine("重新获取节点数据：" + value); } //移除节点 { zookeeperHelper.Delete("/mynode"); Console.WriteLine("移除节点"); } Console.WriteLine("完成"); Console.ReadKey(); } } }
执行结果：
