.NetCore使用Redis，StackExchange.Redis队列，发布与订阅，分布式锁的简单使用
https://www.cnblogs.com/Fengge518/p/13556182.html
环境：之前一直是使用serverStack.Redis的客服端，
今天来使用一下StackExchange.Redis(个人感觉更加的人性化一些，也是免费的，性能也不会差太多)，
版本为StackExchange.Redis V2.1.58 ,Core3.1
简单的说明(专业的术语参考资料网络和官网)：官网地址：https://www.redis.net.cn/
Redis（Remote Dictionary Server )，即远程字典服务是一个开源的 ，由C语言编写、支持网络、可基于内存亦可持久化的日志型、Key-Value数据库，并提供多种语言的API。
Redis 是一个高性能的key-value数据库。Redis的出现，很大程度补偿了memcached这类key/value存储的不足，
提供了Java，C/C++，C#，PHP，JavaScript，Perl，Object-C，Python，Ruby，Erlang等客户端，使用很方便。
优点：
1 Redis读写性能优异，从内存当中进行IO读写速度快，支持超过100K+每秒的读写频率。
2 Redis支持Strings,
Lists, Hashes, Sets,Ordered Sets等数据类型操作。
3 Redis支持数据持久化，支持AOF和RDB两种持久化方式
4 Redis支持主从复制，主机会自动将数据同步到从机，可以进行读写分离。
5 Redis的所有操作都是原子性的，同时Redis还支持对几个操作全并后的原子性执行。
6 Redis是单线程多CPU，不需要考虑加锁释放锁，也就没有死锁的问题，效率高。
1：redis队列值入队出队,截图效果：
优化之前入队1000条数据，测试结果将近50秒，这实在太慢，不可忍受！
优化后的效果：为5.55s的样子
2：redis发布与订阅截图效果：(一个发布者，四个订阅者) 订阅者都会收到相同的信息
3：redis秒杀，截图如下：单个进程秒杀ok
开多个进程时，会有超卖的现象：（那我加lock锁呢？结果也是会有超卖的现象，此时下面的分布式锁可以解决）
4：加上redis分布式锁的测试效果截图：
但是这样会比较耗资源，库存已经没有了，就应该不要再去执行下去了
分布式锁ok库存为零就不在请求直接抛异常即可
上面通过测试的截图，简单的介绍了，Redis的队列(入队和出队)，Redis发布与订阅，Redis分布式锁的使用，现在直接上代码 ：
出队入队的WebApi Core3.1
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace WebApp.Controllers
{
using Microsoft.AspNetCore.Mvc;
using RedisPublishAndSubHelper;
[Route("api/[Controller]")]
[ApiController]
public class RedisTestController
{
[HttpGet("EnqueueMsg")]
public async Task EnqueueMsgAsync(string rediskey, string redisValue)
{
ApiResultObject obj = new ApiResultObject();
try
{
long enqueueLong = default;
for (int i = 0; i < 1000; i++)
{
enqueueLong = await MyRedisSubPublishHelper.EnqueueListLeftPushAsync(rediskey, redisValue + i);
}
obj.Code = ResultCode.Success;
obj.Data = "入队的数据长度：" + enqueueLong;
obj.Msg = "入队成功！";
}
catch (Exception ex)
{
obj.Msg = $"入队异常，原因：{ex.Message}";
}
return obj;
}
[HttpGet("DequeueMsg")]
public async Task DequeueMsgAsync(string rediskey)
{
ApiResultObject obj = new ApiResultObject();
try
{
string dequeueMsg = await MyRedisSubPublishHelper.DequeueListPopRightAsync(rediskey);
obj.Code = ResultCode.Success;
obj.Data = $"出队的数据是：{dequeueMsg}";
obj.Msg = "入队成功！";
}
catch (Exception ex)
{
obj.Msg = $"入队异常，原因：{ex.Message}";
}
return obj;
}
}
}
出队入队的后端code WebApi：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace WebApp.Controllers
{
using Microsoft.AspNetCore.Mvc;
using RedisPublishAndSubHelper;
[Route("api/[Controller]")]
[ApiController]
public class RedisTestController
{
[HttpGet("EnqueueMsg")]
public async Task EnqueueMsgAsync(string rediskey, string redisValue)
{
ApiResultObject obj = new ApiResultObject();
try
{
long enqueueLong = default;
for (int i = 0; i < 1000; i++)
{
enqueueLong = await MyRedisSubPublishHelper.EnqueueListLeftPushAsync(rediskey, redisValue + i);
}
obj.Code = ResultCode.Success;
obj.Data = "入队的数据长度：" + enqueueLong;
obj.Msg = "入队成功！";
}
catch (Exception ex)
{
obj.Msg = $"入队异常，原因：{ex.Message}";
}
return obj;
}
[HttpGet("DequeueMsg")]
public async Task DequeueMsgAsync(string rediskey)
{
ApiResultObject obj = new ApiResultObject();
try
{
string dequeueMsg = await MyRedisSubPublishHelper.DequeueListPopRightAsync(rediskey);
obj.Code = ResultCode.Success;
obj.Data = $"出队的数据是：{dequeueMsg}";
obj.Msg = "入队成功！";
}
catch (Exception ex)
{
obj.Msg = $"入队异常，原因：{ex.Message}";
}
return obj;
}
}
}
入队以及秒杀分布式锁的客服端的Code：
using System;
using System.Threading;
using System.Threading.Tasks;
namespace RedisPublishService
{
using RedisPublishAndSubHelper;
class Program
{
static void Main(string[] args)
{
#region 入队的code
{
int Index = 100000;
while (Index > 0)
{
//string msg = Console.ReadLine();
new MyRedisSubPublishHelper().PublishMessage("nihaofengge", $"你好风哥：Guid值是：{DateTime.Now}{Guid.NewGuid().ToString()}");
Console.WriteLine("发布成功！");
Index -= 1;
}
Console.ReadKey();
}
#endregion
#region 秒杀的code
{
try
{
Console.WriteLine("秒杀开始。。。。。");
for (int i = 0; i < 200; i++)
{
Task.Run(() =>
{
MyRedisSubPublishHelper.LockByRedis("mstest");
string productCount = MyRedisHelper.StringGet("productcount");
int pcount = int.Parse(productCount);
if (pcount > 0)
{
long dlong = MyRedisHelper.StringDec("productcount");
Console.WriteLine($"秒杀成功，商品库存:{dlong}");
pcount -= 1;
System.Threading.Thread.Sleep(30);
}
else
{
Console.WriteLine($"秒杀失败，商品库存为零了！");
throw new Exception("产品秒杀数量为零！");//加载这里会比较保险
}
MyRedisSubPublishHelper.UnLockByRedis("mstest");
}).Wait();
}
}
catch (Exception ex)
{
Console.WriteLine($"产品已经秒杀完毕，原因：{ex.Message}");
}
Console.ReadKey();
}
#endregion
}
}
}
完整的code RedisHelper帮助类(测试并使用了部分方法的封装)，
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace RedisPublishAndSubHelper
{
using StackExchange.Redis;
using StackExchange;
using System.Threading;
public class MyRedisHelper
{
private static readonly string connectionRedisStr = string.Empty;
static MyRedisHelper()
{
//在这里来初始化一些配置信息
connectionRedisStr = "12.23.45.12:6379,connectTimeout=1000,connectRetry=3,syncTimeout=10000";
}
#region Redis string简单的常见同步方法操作
public static bool StringSet(string key, string stringValue, double senconds = 60)
{
using (var conn = ConnectionMultiplexer.Connect(connectionRedisStr))
{
IDatabase db = conn.GetDatabase();
return db.StringSet(key, stringValue, TimeSpan.FromSeconds(senconds));
}
}
public static string StringGet(string key)
{
using (var conn = ConnectionMultiplexer.Connect(connectionRedisStr))
{
IDatabase db = conn.GetDatabase();
return db.StringGet(key);
}
}
public static long StringInc(string key)
{
using (var conn = ConnectionMultiplexer.Connect(connectionRedisStr))
{
IDatabase db = conn.GetDatabase();
return db.StringIncrement(key);
}
}
public static long StringDec(string key)
{
using (var conn = ConnectionMultiplexer.Connect(connectionRedisStr))
{
IDatabase db = conn.GetDatabase();
return db.StringDecrement(key);
}
}
public static bool KeyExists(string key)
{
using (var conn = ConnectionMultiplexer.Connect(connectionRedisStr))
{
IDatabase db = conn.GetDatabase();
return db.KeyExists(key);
}
}
#endregion
#region List Hash, Set,Zset 大同小异的使用，比较简单,后续有时间再补上
#endregion
#region 入队出队
#region 入队
///
/// 入队right
///
///
///
///
/// 入队left
///
///
///
///
/// 入队left异步
///
///
///
/// EnqueueListLeftPushAsync(RedisKey queueName, RedisValue redisvalue)
{
using (var conn = await ConnectionMultiplexer.ConnectAsync(connectionRedisStr))
{
return await conn.GetDatabase().ListLeftPushAsync(queueName, redisvalue);
}
}
///
/// 获取队列的长度
///
///
/// DequeueListPopRightAsync(RedisKey queueName)
{
using (var conn = await ConnectionMultiplexer.ConnectAsync(connectionRedisStr))
{
IDatabase database = conn.GetDatabase();
int count = (await database.ListRangeAsync(queueName)).Length;
if (count <= 0)
{
throw new Exception($"队列{queueName}数据为零");
}
string redisValue = await conn.GetDatabase().ListRightPopAsync(queueName);
if (!string.IsNullOrEmpty(redisValue))
return redisValue;
else
return string.Empty;
}
}
#endregion
#endregion
#region 分布式锁
public static void LockByRedis(string key, int expireTimeSeconds = 10)
{
try
{
IDatabase database1 = ConnectionMultiplexer.Connect(connectionRedisStr).GetDatabase();
while (true)
{
expireTimeSeconds = expireTimeSeconds > 20 ? 10 : expireTimeSeconds;
bool lockflag = database1.LockTake(key, Thread.CurrentThread.ManagedThreadId, TimeSpan.FromSeconds(expireTimeSeconds));
if (lockflag)
{
break;
}
}
}
catch (Exception ex)
{
throw new Exception($"Redis加锁异常:原因{ex.Message}");
}
}
public static bool UnLockByRedis(string key)
{
ConnectionMultiplexer conn = ConnectionMultiplexer.Connect(connectionRedisStr);
try
{
IDatabase database1 = conn.GetDatabase();
return database1.LockRelease(key, Thread.CurrentThread.ManagedThreadId);
}
catch (Exception ex)
{
throw new Exception($"Redis加锁异常:原因{ex.Message}");
}
finally
{
if (conn != null)
{
conn.Close();
conn.Dispose();
}
}
}
#endregion
}
}
using System;
using System.Collections.Generic;
using System.Text;
namespace RedisPublishAndSubHelper
{
using StackExchange.Redis;
using System.Net.Http;
using System.Threading;
using System.Threading.Channels;
using System.Threading.Tasks;
public class MyRedisSubPublishHelper
{
private static readonly string redisConnectionStr = "12.32.12.54:6379,connectTimeout=10000,connectRetry=3,syncTimeout=10000";
private static readonly ConnectionMultiplexer connectionMultiplexer = null;
static MyRedisSubPublishHelper()
{
connectionMultiplexer = ConnectionMultiplexer.Connect(redisConnectionStr);
}
#region 发布订阅
public void SubScriper(string topticName, Action handler = null)
{
ISubscriber subscriber = connectionMultiplexer.GetSubscriber();
ChannelMessageQueue channelMessageQueue = subscriber.Subscribe(topticName);
channelMessageQueue.OnMessage(channelMessage =>
{
if (handler != null)
{
string redisChannel = channelMessage.Channel;
string msg = channelMessage.Message;
handler.Invoke(redisChannel, msg);
}
else
{
string msg = channelMessage.Message;
Console.WriteLine($"订阅到消息: { msg},Channel={channelMessage.Channel}");
}
});
}
public void PublishMessage(string topticName, string message)
{
ISubscriber subscriber = connectionMultiplexer.GetSubscriber();
long publishLong = subscriber.Publish(topticName, message);
Console.WriteLine($"发布消息成功：{publishLong}");
}
#endregion
#region 入队出队
public static async Task EnqueueListLeftPushAsync(RedisKey queueName, RedisValue redisvalue)
{
return await connectionMultiplexer.GetDatabase().ListLeftPushAsync(queueName, redisvalue);
}
public static async Task DequeueListPopRightAsync(RedisKey queueName)
{
IDatabase database = connectionMultiplexer.GetDatabase();
int count = (await database.ListRangeAsync(queueName)).Length;
if (count <= 0)
{
throw new Exception($"队列{queueName}数据为零");
}
string redisValue = await database.ListRightPopAsync(queueName);
if (!string.IsNullOrEmpty(redisValue))
return redisValue;
else
return string.Empty;
}
#endregion
#region 分布式锁
public static void LockByRedis(string key, int expireTimeSeconds = 10)
{
try
{
IDatabase database = connectionMultiplexer.GetDatabase();
while (true)
{
expireTimeSeconds = expireTimeSeconds > 20 ? 10 : expireTimeSeconds;
bool lockflag = database.LockTake(key, Thread.CurrentThread.ManagedThreadId, TimeSpan.FromSeconds(expireTimeSeconds));
if (lockflag)
{
break;
}
}
}
catch (Exception ex)
{
throw new Exception($"Redis加锁异常:原因{ex.Message}");
}
}
public static bool UnLockByRedis(string key)
{
try
{
IDatabase database = connectionMultiplexer.GetDatabase();
return database.LockRelease(key, Thread.CurrentThread.ManagedThreadId);
}
catch (Exception ex)
{
throw new Exception($"Redis加锁异常:原因{ex.Message}");
}
}
#endregion
}
}