ASP.NET結合Redis實現分佈式緩存

 

最近一個項目ASP.NET+MySQL

有的網頁打開初始化的查詢須要10秒甚至更久，用戶體驗極差，並且併發量變大的時候網站容易崩潰

後來想了兩種解決方案都不是太滿意

一、數據庫裏建一張緩存表，後臺做業定時去更新這張表，每次網頁打開就能夠直接從緩存表裏查詢

二、用戶第一次打開網站將數據已文件的形式緩存到服務器上，下次直接從文件中讀取數據

最後決定用Redis分佈式緩存實現

Redis是在Linux系統上安裝的，不過也有Windows版本的安裝包，我是將它設置成了服務

下載地址 https://github.com/MicrosoftArchive/redis/releases

解壓後目錄結構以下

以管理員方式打開命令行，跳轉到Redis解壓的目錄下，執行命令 redis-server --service-install redis.windows.conf

會提示服務安裝成功

打開計算機管理->服務，已經能夠看到Redis服務了，將它設置爲開機自動運行

接下來，要使用ServiceStack.Redis在C#中操做Redis

能夠經過Nuget安裝，也能夠到網上下載這個類庫

最新版本的版本(好像是5.0)是收費的，免費版一個小時以內有緩存6000次的限制。

若是須要破解版能夠聯繫我QQ 22378930

固然也可使用比較舊的ServiceStack版本，好比3.0

首先添加ServiceStack的引用

ServiceStack.Common.dll

ServiceStack.Interfaces.dll

ServiceStack.Redis.dll

ServiceStack.Text.dll

添加引用後，在web.config中添加一些配置

 <appSettings>
    <add key="WriteServerList" value="127.0.0.1:6379" />
    <add key="ReadServerList" value="127.0.0.1:6379" />
    <add key="MaxWritePoolSize" value="60" />
    <add key="MaxReadPoolSize" value="60" />
    <add key="AutoStart" value="true" />
    <add key="LocalCacheTime" value="1800" />
    <add key="RecordeLog" value="false" />
  </appSettings>

配置文件操做類

 public class RedisConfigInfo
    {
        public static string WriteServerList = ConfigurationManager.AppSettings["WriteServerList"];
        public static string ReadServerList = ConfigurationManager.AppSettings["ReadServerList"];
        public static int MaxWritePoolSize = Convert.ToInt32(ConfigurationManager.AppSettings["MaxWritePoolSize"]);
        public static int MaxReadPoolSize = Convert.ToInt32(ConfigurationManager.AppSettings["MaxReadPoolSize"]);
        public static int LocalCacheTime = Convert.ToInt32(ConfigurationManager.AppSettings["LocalCacheTime"]);
        public static bool AutoStart = ConfigurationManager.AppSettings["AutoStart"].Equals("true") ? true : false;
    }

鏈接Redis,以及其餘的一些操做類

public class RedisManager
    {
        private static PooledRedisClientManager prcm;

        /// <summary>
        /// 建立連接池管理對象
        /// </summary>
        private static void CreateManager()
        {
            string[] writeServerList = SplitString(RedisConfigInfo.WriteServerList, ",");
            string[] readServerList = SplitString(RedisConfigInfo.ReadServerList, ",");

            prcm = new PooledRedisClientManager(readServerList, writeServerList,
                             new RedisClientManagerConfig
                             {
                                 MaxWritePoolSize = RedisConfigInfo.MaxWritePoolSize,
                                 MaxReadPoolSize = RedisConfigInfo.MaxReadPoolSize,
                                 AutoStart = RedisConfigInfo.AutoStart,
                             });
        }

        private static string[] SplitString(string strSource, string split)
        {
            return strSource.Split(split.ToArray());
        }

        /// <summary>
        /// 客戶端緩存操做對象
        /// </summary>
        public static IRedisClient GetClient()
        {
            if (prcm == null)
                CreateManager();

            return prcm.GetClient();
        }
        /// <summary>
        /// 緩存默認24小時過時
        /// </summary>
        public static TimeSpan expiresIn = TimeSpan.FromHours(24);
        /// <summary>
        /// 設置一個鍵值對，默認24小時過時
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key"></param>
        /// <param name="value"></param>
        /// <param name="redisClient"></param>
        /// <returns></returns>
        public static bool Set<T>(string key, T value, IRedisClient redisClient)
        {

            return redisClient.Set<T>(key, value, expiresIn);
        }

        /// <summary>
        /// 將某類數據插入到list中
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key">通常是BiaoDiGuid</param>
        /// <param name="item"></param>
        /// <param name="redisClient"></param>
        public static void Add2List<T>(string key, T item, IRedisClient redisClient)
        {
            var redis = redisClient.As<T>();
            var list = redis.Lists[GetListKey(key)];
            list.Add(item);
        }

        /// <summary>
        /// 獲取一個list
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key"></param>
        /// <param name="redisClient"></param>
        /// <returns></returns>
        public static IRedisList<T> GetList<T>(string key, IRedisClient redisClient)
        {
            var redis = redisClient.As<T>();
            return redis.Lists[GetListKey(key)];
        }

        public static string GetListKey(string key, string prefix = null)
        {
            if (string.IsNullOrEmpty(prefix))
            {
                return "urn:" + key;
            }
            else
            {
                return "urn:" + prefix + ":" + key;
            }
        }
    }

下面咱們來測試一下是否可以成功讀取Redis緩存

 <form id="form1" runat="server">
    <div>
        <asp:Label runat="server" ID="lbtest"></asp:Label>
        <asp:Button runat="server" ID ="btn1" OnClick="btn1_Click" Text="獲取測試數據"/>
    </div>
    </form>

 protected void btn1_Click(object sender, EventArgs e)
        {
            string UserName;
            //讀取數據，若是緩存存在直接從緩存中讀取，不然從數據庫讀取而後寫入redis
            using (var redisClient = RedisManager.GetClient())
            {
                UserName = redisClient.Get<string>("UserInfo_123");
                if (string.IsNullOrEmpty(UserName)) //初始化緩存
                {
                    //TODO 從數據庫中獲取數據，並寫入緩存
                    UserName = "張三";
                    redisClient.Set<string>("UserInfo_123", UserName, DateTime.Now.AddSeconds(10));
                    lbtest.Text = "數據庫數據：" + "張三";
                    return;
                }
                lbtest.Text = "Redis緩存數據：" + UserName;
            }
        }

首次訪問緩存中數據不存在，獲取數據並寫入緩存，並設定有效期10秒

10秒內再次訪問讀取緩存中數據