asp.net mvc 用Redis实现分布式集群共享Session。

1、这两天研究Redis搞分布式session问题，网上找的资料都是用ServiceStack.Redis来实现的，但是在做性能测试的时候发现最新的v4版本有限制每小时候最多请求6000次，因为官网开始商业化要收费了，好坑爹的说，还好我前期弄了个性能测试列子，不然上线以后出问题那就麻烦了。后面找了个NServiceKit.Redis（好像就是ServiceStack.Redis的v3版本）来替代v4的收费版。

2、解决方案是 Redis+cookie方式实现记录用户登录状态

cookie：存放用户的ID，这个ID是经过加密的，并且后台可以通过密钥解密。

Redis：key/value 方式存储，key存放比如：user_1。 value存放用户实体对象。

3、先安装一个Redis，windows的版本在本地进行测试，后期上线更换linux系统的Redis替换一下ip就可以了。

4、添加一个Session管理类

public class SessionHelper
{
private const int secondsTimeOut = 60 * 20;  //默认过期时间20分钟  单位秒

public RedisHelper Redis = new RedisHelper(false);
public LoginUserInfo this[string key]
{
get
{
string webCookie = WebHelper.GetCookie(key);
if (webCookie == "")
{
return null;
}
key = key + "_" + SecureHelper.AESDecrypt(webCookie);

//距离过期时间还有多少秒
long l = Redis.TTL(key);
if (l >= 0)
{
Redis.Expire(key, secondsTimeOut);
}

return Redis.Get<LoginUserInfo>(key);
}
set
{
SetSession(key, value);
}
}
public void SetSession(string key, LoginUserInfo value)
{
if (string.IsNullOrWhiteSpace(key))
{
throw new Exception("Key is Null or Epmty");
}
WebHelper.SetCookie(key, SecureHelper.AESEncrypt(value.ID.ToString()));
key = key + "_" + value.ID;
Redis.Set<LoginUserInfo>(key, value, secondsTimeOut);
}

/// <summary>
/// 移除Session
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public bool Remove(string key)
{
var rs = Redis.Remove(key + "_" + SecureHelper.AESDecrypt(WebHelper.GetCookie(key)));
WebHelper.DeleteCookie(key);
return rs;
}

}

5、Redis操作类

public class RedisHelper : IDisposable
{
private RedisClient Redis = new RedisClient("127.0.0.1", 6379);
//缓存池
PooledRedisClientManager prcm = new PooledRedisClientManager();

//默认缓存过期时间单位秒
public int secondsTimeOut = 20 * 60;

/// <summary>
/// 缓冲池
/// </summary>
/// <param name="readWriteHosts"></param>
/// <param name="readOnlyHosts"></param>
/// <returns></returns>
public static PooledRedisClientManager CreateManager(string[] readWriteHosts, string[] readOnlyHosts)
{
return new PooledRedisClientManager(readWriteHosts, readOnlyHosts,
new RedisClientManagerConfig
{
MaxWritePoolSize = readWriteHosts.Length * 5,
MaxReadPoolSize = readOnlyHosts.Length * 5,
AutoStart = true,
});
}
/// <summary>
/// 构造函数
/// </summary>
/// <param name="OpenPooledRedis">是否开启缓冲池</param>
public RedisHelper(bool OpenPooledRedis = false)
{

if (OpenPooledRedis)
{
prcm = CreateManager(new string[] { "127.0.0.1:6379" }, new string[] { "127.0.0.1:6379" });
Redis = prcm.GetClient() as RedisClient;
}
}
/// <summary>
/// 距离过期时间还有多少秒
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public long TTL(string key)
{
return Redis.Ttl(key);
}
/// <summary>
/// 设置过期时间
/// </summary>
/// <param name="key"></param>
/// <param name="timeout"></param>
public void Expire(string key,int timeout = 0)
{
if (timeout >= 0)
{
if (timeout > 0)
{
secondsTimeOut = timeout;
}
Redis.Expire(key, secondsTimeOut);
}
}

#region Key/Value存储
/// <summary>
/// 设置缓存
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="key">缓存建</param>
/// <param name="t">缓存值</param>
/// <param name="timeout">过期时间，单位秒,-1：不过期，0：默认过期时间</param>
/// <returns></returns>
public bool Set<T>(string key, T t, int timeout = 0)
{
Redis.Set<T>(key, t);
if (timeout >= 0)
{
if (timeout > 0)
{
secondsTimeOut = timeout;
}
Redis.Expire(key, secondsTimeOut);
}
return true;

}
/// <summary>
/// 获取
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="key"></param>
/// <returns></returns>
public T Get<T>(string key)
{
return Redis.Get<T>(key);
}
/// <summary>
/// 删除
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public bool Remove(string key)
{
return Redis.Remove(key);
}
#endregion

//释放资源
public void Dispose()
{
if (Redis != null)
{
Redis.Dispose();
Redis = null;
}
GC.Collect();

}
}