.net core microservices 架构之 分布式
2024-08-27 13:33:27
.net core microservices 架构之 分布式
一：简介
自动计算都是常驻内存的，没有人机交互。我们经常用到的就是console job和sql job了。sqljob有自己的宿主，与数据库产品有很关联，暂时不提。console job使用quartz.net框架，目前3.x已经支持netcore。
如果单台服务器运行计算，那就很简单了，quartz很强大了，而且支持故障灾难转移集群，docker做宿主，很容易实现。但是分布式就不可同日而语了。如果你的一个数据处理太慢，需要多进程多主机处理，那么就需要多进程自动协调处理这一数据，比如如果你的订单太多，而一个进程处理延迟是10秒，那用户体验就会非常不好，虽然异步已经提高了你的吞吐量，但是延迟太久，对后续业务还是造成很大的干扰，时不时的会进行停顿。如果两到三台的机器进行处理，那延迟就会大大的减低，但是这两到三台服务器如果分配处理任务？如何分割这个数据，多进程进行处理？就需要到这一篇讲解的知识了。
在多个job应用之间进行协调的工具，就是zookeeper了，zookeeper官方介绍：一个分布式应用协调服务。其实他也是一个类似文件系统的写一致的数据存储软件，我们可以使用它做分布式锁，对应用进行协调控制。
目前流行的这一类产品也比较多，但是我是熟悉quartz，至于切片的功能，在quartz之上可以进行封装，因为所要封装的功能不多，所以我还是选择了quartz。
二 zookeeper 服务
首先就是zookeeper服务，和前面log日志一样，首先创建构建和配置文件类。
首先看看配置类：
ZookeeperConfiguration.cs
using Microsoft.Extensions.Configuration; namespace Walt.Framework.Configuration
{
public class ZookeeperConfiguration
{
public IConfiguration Configuration { get; } public ZookeeperConfiguration(IConfiguration configuration)
{
Configuration = configuration;
}
} }
ZookeeperConfigurationExtensioncs.cs
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Options;
using Walt.Framework.Service.Zookeeper; namespace Walt.Framework.Configuration
{
public static class ZookeeperConfigurationExtensioncs
{
public static IZookeeperBuilder AddConfiguration(this IZookeeperBuilder builder
,IConfiguration configuration)
{ InitService( builder,configuration);
return builder;
} public static void InitService(IZookeeperBuilder builder,IConfiguration configuration)
{
builder.Services.TryAddSingleton<IConfigureOptions<ZookeeperOptions>>(
new ZookeeperConfigurationOptions(configuration)); builder.Services.TryAddSingleton
(ServiceDescriptor.Singleton<IOptionsChangeTokenSource<ZookeeperOptions>>(
new ConfigurationChangeTokenSource<ZookeeperOptions>(configuration)) ); builder.Services
.TryAddEnumerable(ServiceDescriptor.Singleton<IConfigureOptions<ZookeeperOptions>>
(new ConfigureFromConfigurationOptions<ZookeeperOptions>(configuration))); builder.Services.AddSingleton(new ZookeeperConfiguration(configuration));
}
}
}
ZookeeperConfigurationOptions.cs
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Options;
using Walt.Framework.Service.Zookeeper; namespace Walt.Framework.Configuration
{
public class ZookeeperConfigurationOptions : IConfigureOptions<ZookeeperOptions>
{ private readonly IConfiguration _configuration; public ZookeeperConfigurationOptions(IConfiguration configuration)
{
_configuration=configuration;
} public void Configure(ZookeeperOptions options)
{
System.Diagnostics.Debug.WriteLine("zookeeper配置类，适配方法。"
+Newtonsoft.Json.JsonConvert.SerializeObject(options));
}
}
}
以上这三个类就是配置类，下面是构建类和配置信息类：
ZookeeperBuilder.cs
using Microsoft.Extensions.DependencyInjection; namespace Walt.Framework.Service.Zookeeper
{
public class ZookeeperBuilder : IZookeeperBuilder
{
public IServiceCollection Services {get;} public ZookeeperBuilder(IServiceCollection services)
{
Services=services;
}
}
}
ZookeeperOptions.cs
using System;
using System.Collections.Generic; namespace Walt.Framework.Service.Zookeeper
{
public class ZookeeperOptions
{
/// <param name="connectstring">comma separated host:port pairs, each corresponding to a zk server.
/// e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002" If the optional chroot suffix is used the example would look like:
/// "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002/app/a" where the client would be rooted at "/app/a" and all paths would
/// be relative to this root - ie getting/setting/etc... "/foo/bar" would result in operations being run on "/app/a/foo/bar"
/// (from the server perspective).</param>
public string Connectstring{get;set;} public int SessionTimeout{get;set;} public int SessionId{get;set;} public string SessionPwd{get;set;} public bool IsReadOnly{get;set;} }
}
ZookeeperService.cs 这个类中有两个watch类。
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using org.apache.zookeeper;
using org.apache.zookeeper.data;
using static org.apache.zookeeper.ZooKeeper;
using System.Linq;
using System.Linq.Expressions;
using System.Threading;
using static org.apache.zookeeper.Watcher.Event;
using Newtonsoft.Json;
using System.Collections.Concurrent; namespace Walt.Framework.Service.Zookeeper
{ internal class WaitLockWatch:Watcher
{
private AutoResetEvent _autoResetEvent;
private ILogger _logger; private string _path; private ZookeeperService _zookeeperService; public string _tempNode; public WaitLockWatch(AutoResetEvent autoResetEvent
,ZookeeperService zookeeperService
,ILogger logger,string path
,string tempNode)
{
_autoResetEvent=autoResetEvent;
_zookeeperService=zookeeperService;
_logger=logger;
_path=path;
_tempNode=tempNode;
} public override Task process(WatchedEvent @event)
{
_logger.LogDebug("{0}节点下子节点发生改变，激发监视方法。",_path);
var childList=_zookeeperService.GetChildrenAsync(_path,null,true).Result;
if(childList==null||childList.Children==null||childList.Children.Count<1)
{
_logger.LogDebug("获取子序列失败，计数为零.path:{0}",_path);
return Task.FromResult(0);
}
var top=childList.Children.OrderBy(or=>or).First();
if(_path+"/"+top==_tempNode)
{
_logger.LogDebug("释放阻塞");
_autoResetEvent.Set();
} return Task.FromResult(0);
}
} internal class WaitConnWatch : Watcher
{
private AutoResetEvent _autoResetEvent;
private ILogger _logger; public WaitConnWatch(AutoResetEvent autoResetEvent
,ILogger logger)
{
_autoResetEvent=autoResetEvent;
_logger=logger;
} public override Task process(WatchedEvent @event)
{
_logger.LogDebug("watch激发,回掉状态：{0}",@event.getState().ToString());
if(@event.getState()== KeeperState.SyncConnected
||@event.getState()== KeeperState.ConnectedReadOnly)
{
_logger.LogDebug("释放阻塞");
_autoResetEvent.Set();
}
return Task.FromResult(0);
}
} public class ZookeeperService : IZookeeperService
{ public List<string> requestLockSequence=new List<string>();
private object _lock=new object();
private ZookeeperOptions _zookeeperOptions;
private ZooKeeper _zookeeper; private static readonly byte[] NO_PASSWORD = new byte[0]; public Watcher Wathcer {get;set;} public ILoggerFactory LoggerFac { get; set; } private ILogger _logger; AutoResetEvent[] autoResetEvent=new AutoResetEvent[2]
{new AutoResetEvent(false),new AutoResetEvent(false)}; public ZookeeperService(IOptionsMonitor<ZookeeperOptions> zookeeperOptions
,ILoggerFactory loggerFac)
{
LoggerFac=loggerFac;
_logger=LoggerFac.CreateLogger<ZookeeperService>();
_zookeeperOptions=zookeeperOptions.CurrentValue;
_logger.LogDebug("配置参数：{0}",JsonConvert.SerializeObject(_zookeeperOptions));
zookeeperOptions.OnChange((zookopt,s)=>{
_zookeeperOptions=zookopt;
});
_logger.LogDebug("开始连接");
Conn(_zookeeperOptions);
} private void Conn(ZookeeperOptions zookeeperOptions)
{
bool isReadOnly=default(Boolean);
Wathcer=new WaitConnWatch(autoResetEvent[0],_logger);
if(isReadOnly!=zookeeperOptions.IsReadOnly)
{
isReadOnly=zookeeperOptions.IsReadOnly;
} byte[] pwd=new byte[0];
//如果没有密码和sessionId
if(string.IsNullOrEmpty(zookeeperOptions.SessionPwd)
&&_zookeeperOptions.SessionId==default(int))
{
_zookeeper=new ZooKeeper(zookeeperOptions.Connectstring,zookeeperOptions.SessionTimeout,Wathcer,isReadOnly);
}
else if (!string.IsNullOrEmpty(zookeeperOptions.SessionPwd))
{
pwd=System.Text.Encoding.Default.GetBytes(zookeeperOptions.SessionPwd);
_zookeeper=new ZooKeeper(zookeeperOptions.Connectstring,zookeeperOptions.SessionTimeout,Wathcer,0,pwd,isReadOnly);
}
else
{
_zookeeper=new ZooKeeper(zookeeperOptions.Connectstring
,zookeeperOptions.SessionTimeout,Wathcer,zookeeperOptions.SessionId,pwd,isReadOnly);
}
if(_zookeeper.getState()==States.CONNECTING)
{
_logger.LogDebug("当前状态：CONNECTING。阻塞等待");
autoResetEvent[0].WaitOne();
}
} public Task<string> CreateZNode(string path,string data,CreateMode createMode,List<ACL> aclList)
{
ReConn();
if(string.IsNullOrEmpty(path)||!path.StartsWith('/'))
{
_logger.LogDebug("path路径非法，参数：path：{0}",path);
return null;
}
byte[] dat=new byte[0];
if(string.IsNullOrEmpty(data))
{
dat=System.Text.Encoding.Default.GetBytes(data);
}
if(createMode==null)
{
_logger.LogDebug("createMode为null,默认使用CreateMode.PERSISTENT");
createMode=CreateMode.PERSISTENT;
}
return _zookeeper.createAsync(path,dat,aclList,createMode);
} public Task<DataResult> GetDataAsync(string path,Watcher watcher,bool isSync)
{
ReConn();
if(_zookeeper.existsAsync(path).Result==null )
{
_logger.LogDebug("path不存在");
return null;
}
if(isSync)
{
_logger.LogDebug("即将进行同步。");
var task=Task.Run(async ()=>{
await _zookeeper.sync(path);
});
task.Wait();
} return _zookeeper.getDataAsync(path,watcher);
} public Task<Stat> SetDataAsync(string path,string data,bool isSync)
{
ReConn();
if(_zookeeper.existsAsync(path).Result==null )
{
_logger.LogDebug("path不存在");
return null;
}
byte[] dat=new byte[0];
if(!string.IsNullOrEmpty(data))
{
dat=System.Text.Encoding.Default.GetBytes(data);
}
return _zookeeper.setDataAsync(path,dat);
} public async Task<ChildrenResult> GetChildrenAsync(string path,Watcher watcher,bool isSync)
{
ReConn();
if(_zookeeper.existsAsync(path).Result==null )
{
_logger.LogDebug("path不存在");
return null;
}
if(isSync)
{
_logger.LogDebug("即将进行同步。");
var task=Task.Run(async ()=>{
_logger.LogDebug("开始同步");
await _zookeeper.sync(path);
});
task.Wait();
}
return await _zookeeper.getChildrenAsync(path,watcher);
} public void DeleteNode(string path,String tempNode)
{
if(!string.IsNullOrEmpty(tempNode))
{
requestLockSequence.Remove(tempNode);
}
ReConn();
if(_zookeeper.existsAsync(path).Result==null )
{
_logger.LogDebug("path不存在");
return;
}
var task=Task.Run(async ()=>{
_logger.LogDebug("删除node：{0}",path);
await _zookeeper.deleteAsync(path);
});
task.Wait();
var sequencePath=requestLockSequence.Where(w=>path==w).FirstOrDefault();
if(sequencePath!=null)
{
requestLockSequence.Remove(sequencePath);
}
} public string GetDataByLockNode(string path,string sequenceName,List<ACL> aclList,out string tempNodeOut)
{
_logger.LogInformation("获取分布式锁开始。");
ReConn();
string tempNode=string.Empty;
tempNodeOut=string.Empty; if(_zookeeper.existsAsync(path).Result==null )
{
_logger.LogDebug("path不存在");
return null;
} try
{
_logger.LogDebug("开始锁定语句块");
lock(_lock)
{
_logger.LogDebug("锁定，访问requestLockSequence的代码应该同步。");
tempNode=requestLockSequence
.Where(w=>w.StartsWith(path+"/"+sequenceName)).FirstOrDefault(); if(tempNode==null)
{
tempNode=CreateZNode(path+"/"+sequenceName,"",CreateMode.EPHEMERAL_SEQUENTIAL,aclList).Result;
_logger.LogDebug("创建节点：{0}",tempNode);
if(tempNode==null)
{
_logger.LogDebug("创建临时序列节点失败。详细参数:path:{0},data:{1},CreateMode:{2}"
,path+"/squence","",CreateMode.EPHEMERAL_SEQUENTIAL);
return null;
}
_logger.LogInformation("创建成功，加入requestLockSequence列表。");
requestLockSequence.Add(tempNode);
}
else
{
_logger.LogDebug("已经存在的锁节点，返回null");
return null;
}
} var childList= GetChildrenAsync(path,null,true).Result;
if(childList==null||childList.Children==null||childList.Children.Count<1)
{
_logger.LogDebug("获取子序列失败，计数为零.path:{0}",path);
return null;
}
_logger.LogDebug("获取path:{0}的子节点：{1}",path,Newtonsoft.Json.JsonConvert.SerializeObject(childList.Children));
var top=childList.Children.OrderBy(or=>or).First();
byte[] da=null;
if(path+"/"+top==tempNode)
{
tempNodeOut =tempNode;
da= GetDataAsync(path,null,true).Result.Data;
if(da==null||da.Length<1)
{
return string.Empty;
}
return System.Text.Encoding.Default.GetString(da);
}
else
{
childList= GetChildrenAsync(path,new WaitLockWatch(autoResetEvent[1],this,_logger,path,tempNode),true).Result;
autoResetEvent[1].WaitOne();
}
_logger.LogDebug("继续执行。");
tempNodeOut =tempNode;
da= GetDataAsync(path,null,true).Result.Data;
if(da==null||da.Length<1)
{
return string.Empty;
}
return System.Text.Encoding.Default.GetString(da);
}
catch(Exception ep)
{
_logger.LogError(ep,"获取同步锁出现错误。");
if(!string.IsNullOrEmpty(tempNode))
{
DeleteNode(tempNode,tempNode);
}
}
return null;
} private void ReConn()
{
_logger.LogInformation("检查连接状态");
if(_zookeeper.getState()==States.CLOSED
||_zookeeper.getState()== States.NOT_CONNECTED)
{
_logger.LogInformation("连接为关闭，开始重新连接。");
Conn(_zookeeperOptions);
}
} public void Close(string tempNode)
{
var task=Task.Run(async ()=>{
requestLockSequence.Remove(tempNode);
await _zookeeper.closeAsync();
});
task.Wait();
} }
}
前面的类如果了解了netcore的扩展服务和配置机制，就很简单理解了，我们主要是讲解这个服务类的功能。
首先看服务类其中的一段代码：
private void Conn(ZookeeperOptions zookeeperOptions)
{
bool isReadOnly=default(Boolean);
Wathcer=new WaitConnWatch(autoResetEvent[0],_logger); //监控连接是否连接成功
if(isReadOnly!=zookeeperOptions.IsReadOnly)
{
isReadOnly=zookeeperOptions.IsReadOnly;
} byte[] pwd=new byte[0];
//如果没有密码和sessionId
if(string.IsNullOrEmpty(zookeeperOptions.SessionPwd)
&&_zookeeperOptions.SessionId==default(int))
{
_zookeeper=new ZooKeeper(zookeeperOptions.Connectstring,zookeeperOptions.SessionTimeout,Wathcer,isReadOnly);
}
else if (!string.IsNullOrEmpty(zookeeperOptions.SessionPwd))
{
pwd=System.Text.Encoding.Default.GetBytes(zookeeperOptions.SessionPwd);
_zookeeper=new ZooKeeper(zookeeperOptions.Connectstring,zookeeperOptions.SessionTimeout,Wathcer,0,pwd,isReadOnly);
}
else
{
_zookeeper=new ZooKeeper(zookeeperOptions.Connectstring
,zookeeperOptions.SessionTimeout,Wathcer,zookeeperOptions.SessionId,pwd,isReadOnly);
}
if(_zookeeper.getState()==States.CONNECTING)
{
_logger.LogDebug("当前状态：CONNECTING。阻塞等待");
autoResetEvent[0].WaitOne();
}
}
这个方法是连接zookeeper，我们在构造函数中调用它，注意，zookeeper是异步，所以需要watcher类监控和AutoResetEvent阻塞当前线程，因为如果不阻塞，在连接还没建立的时候，后面调用，
会出现错误。在监控类被触发的时候，执行取消阻塞。
internal class WaitConnWatch : Watcher
{
private AutoResetEvent _autoResetEvent;
private ILogger _logger; public WaitConnWatch(AutoResetEvent autoResetEvent
,ILogger logger)
{
_autoResetEvent=autoResetEvent;
_logger=logger;
} public override Task process(WatchedEvent @event)
{
_logger.LogDebug("watch激发,回掉状态：{0}",@event.getState().ToString());
if(@event.getState()== KeeperState.SyncConnected
||@event.getState()== KeeperState.ConnectedReadOnly)
{
_logger.LogDebug("释放阻塞");
_autoResetEvent.Set(); //取消阻塞当前线程。
}
return Task.FromResult(0);
}
}
大家看zookeeper服务类，里面很多方法在执行前需要执行conn方法，这只是一种失败重连的机制，因为一般没有线程池的，我都会给这个服务单例。哪有人会问，如果失败重连，会不会阻塞当前应用，
这个不会，因为netcore是多线程的，但是会降低这个应用的生产力。我前面翻译过一篇net的关于线程的知识，后面也会单独一篇讲解netcore的线程模型。还有代码中我很少用异常去处理容错性，尽量抛出原生的异常，使用日志去记录，然后为这个类返回个null，异常对性能也有一定的消耗，当然看自己习惯了，目的都是为了应用的健壮性。
其他方法是操作zookeeper的类，大家可以看我贴出来的代码。因为zookeeper最出名的估计就是分布式锁了，所以就把这个功能加进来。
public string GetDataByLockNode(string path,string sequenceName,List<ACL> aclList,out string tempNodeOut)
{
_logger.LogInformation("获取分布式锁开始。");
ReConn();
string tempNode=string.Empty;
tempNodeOut=string.Empty; if(_zookeeper.existsAsync(path).Result==null )
{
_logger.LogDebug("path不存在");
return null;
} try
{
_logger.LogDebug("开始锁定语句块");
lock(_lock) //这是我为了防止重复提交做的防止并发，当然实际用的地方是协调应用之间的功能，而肯定不会用人机交互。你可以把这个看作多此一举。
{
_logger.LogDebug("锁定，访问requestLockSequence的代码应该同步。");
tempNode=requestLockSequence
.Where(w=>w.StartsWith(path+"/"+sequenceName)).FirstOrDefault(); if(tempNode==null)
{
tempNode=CreateZNode(path+"/"+sequenceName,"",CreateMode.EPHEMERAL_SEQUENTIAL,aclList).Result;
_logger.LogDebug("创建节点：{0}",tempNode);
if(tempNode==null)
{
_logger.LogDebug("创建临时序列节点失败。详细参数:path:{0},data:{1},CreateMode:{2}"
,path+"/squence","",CreateMode.EPHEMERAL_SEQUENTIAL);
return null;
}
_logger.LogInformation("创建成功，加入requestLockSequence列表。");
requestLockSequence.Add(tempNode);
}
else
{
_logger.LogDebug("已经存在的锁节点，返回null");
return null;
}
} var childList= GetChildrenAsync(path,null,true).Result; //首先获取lock子节点。
if(childList==null||childList.Children==null||childList.Children.Count<1)
{
_logger.LogDebug("获取子序列失败，计数为零.path:{0}",path);
return null;
}
_logger.LogDebug("获取path:{0}的子节点：{1}",path,Newtonsoft.Json.JsonConvert.SerializeObject(childList.Children));
var top=childList.Children.OrderBy(or=>or).First();
byte[] da=null;
if(path+"/"+top==tempNode) //判断是否是当前自己的节点在队列顶端。
{
tempNodeOut =tempNode;
da= GetDataAsync(path,null,true).Result.Data;
if(da==null||da.Length<1)
{
return string.Empty;
}
return System.Text.Encoding.Default.GetString(da);
}
else
{
childList= GetChildrenAsync(path,new WaitLockWatch(autoResetEvent[1],this,_logger,path,tempNode),true).Result; //如果自己不再队列顶端，则加监听等待这个节点有更改。
autoResetEvent[1].WaitOne();
}
_logger.LogDebug("继续执行。");
tempNodeOut =tempNode;
da= GetDataAsync(path,null,true).Result.Data;
if(da==null||da.Length<1)
{
return string.Empty;
}
return System.Text.Encoding.Default.GetString(da);
}
catch(Exception ep)
{
_logger.LogError(ep,"获取同步锁出现错误。");
if(!string.IsNullOrEmpty(tempNode))
{
DeleteNode(tempNode,tempNode);
}
}
return null;
}
接下来看监听类：
internal class WaitLockWatch:Watcher
{
private AutoResetEvent _autoResetEvent;
private ILogger _logger; private string _path; private ZookeeperService _zookeeperService; public string _tempNode; public WaitLockWatch(AutoResetEvent autoResetEvent
,ZookeeperService zookeeperService
,ILogger logger,string path
,string tempNode)
{
_autoResetEvent=autoResetEvent;
_zookeeperService=zookeeperService;
_logger=logger;
_path=path;
_tempNode=tempNode;
} public override Task process(WatchedEvent @event)
{
_logger.LogDebug("{0}节点下子节点发生改变，激发监视方法。",_path);
var childList=_zookeeperService.GetChildrenAsync(_path,null,true).Result;
if(childList==null||childList.Children==null||childList.Children.Count<1)
{
_logger.LogDebug("获取子序列失败，计数为零.path:{0}",_path);
return Task.FromResult(0);
}
var top=childList.Children.OrderBy(or=>or).First();
if(_path+"/"+top==_tempNode) //判断当前节点是否队列顶端
{
_logger.LogDebug("释放阻塞");
_autoResetEvent.Set();
} return Task.FromResult(0);
}
}
这个类，在path节点每次更改或者子节点更改的时候都会激发，仅仅是判断当前节点是不是列表的顶端，再执行 _autoResetEvent.Set();释放阻塞让继续执行。
编译提交nuget，然后集成到测试程序看效果。
首先看zookeeper：
目前节点下没有一个子节点，再看看这个节点的值：
首先新建一个看看：
create -s -e /testzookeeper/sequence ""
然后启动程序，当程序提交一个子节点，他是排序的：
我们删除我们刚刚用命令行创建的节点：
delete /testzookeeper/sequence0000000072
然后再看值：
我们的客户端就是获取到锁后更改这个值，增加了一段字符串，客户端调用如下：
[HttpGet("{id}")]
public ActionResult<string> Get(int id)
{
string sequenceNode=string.Empty;
string nodename=_zookeeperService.GetDataByLockNode("/testzookeeper","sequence",ZooDefs.Ids.OPEN_ACL_UNSAFE,out sequenceNode);
if(sequenceNode==null)
{
return "获取分布式锁失败，请查看日志。";
}
_zookeeperService.SetDataAsync("/testzookeeper",nodename+"执行了"+DateTime.Now.ToString("yyyyMMddhhmmss"),false);
if(!string.IsNullOrEmpty(sequenceNode))
{
_zookeeperService.DeleteNode(sequenceNode,sequenceNode);
return "取得锁并且成功处理数据，释放锁成功。";
}
return "出现错误，请查日志。";
}
当然这个是我做测试用的，实际开发，web就是用来做他的数据库存取的，尽量不要去做一些额外的功能，因为i守护进程或者后台服务和job有它自己的任务。
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