5、加入缓存支持
我们希望为项目增加缓存支持，我们选择Redis做为缓存数据库。
首先，我们在Services目录增加一个缓存接口类ICacheService：
| using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; namespace ChainStoreAPI.Services { public interface ICacheService { /// <summary> /// 验证缓存项是否存在 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> bool Exists(string key); /// <summary> /// 验证缓存项是否存在（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> Task<bool> ExistsAsync(string key); /// <summary> /// 添加缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <returns></returns> bool Add(string key, object value); /// <summary> /// 添加缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <returns></returns> Task<bool> AddAsync(string key, object value); /// <summary> /// 添加缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <param name="expiresSliding">滑动过期时长（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <param name="expiressAbsoulte">绝对过期时长</param> /// <returns></returns> bool Add(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte); /// <summary> /// 添加缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <param name="expiresSliding">滑动过期时长（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <param name="expiressAbsoulte">绝对过期时长</param> /// <returns></returns> Task<bool> AddAsync(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte); /// <summary> /// 添加缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <param name="expiresIn">缓存时长</param> /// <param name="isSliding">是否滑动过期（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <returns></returns> bool Add(string key, object value, TimeSpan expiresIn, bool isSliding = false); /// <summary> /// 添加缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <param name="expiresIn">缓存时长</param> /// <param name="isSliding">是否滑动过期（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <returns></returns> Task<bool> AddAsync(string key, object value, TimeSpan expiresIn, bool isSliding = false); /// <summary> /// 删除缓存 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> bool Remove(string key); /// <summary> /// 删除缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> Task<bool> RemoveAsync(string key); /// <summary> /// 批量删除缓存 /// </summary> /// <param name="key">缓存Key集合</param> /// <returns></returns> void RemoveAll(IEnumerable<string> keys); /// <summary> /// 批量删除缓存（异步方式） /// </summary> /// <param name="key">缓存Key集合</param> /// <returns></returns> Task RemoveAllAsync(IEnumerable<string> keys); /// <summary> /// 获取缓存 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> T Get<T>(string key) where T : class; /// <summary> /// 获取缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> Task<T> GetAsync<T>(string key) where T : class; /// <summary> /// 获取缓存 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> object Get(string key); /// <summary> /// 获取缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> Task<object> GetAsync(string key); /// <summary> /// 获取缓存集合 /// </summary> /// <param name="keys">缓存Key集合</param> /// <returns></returns> IDictionary<string, object> GetAll(IEnumerable<string> keys); /// <summary> /// 获取缓存集合（异步方式） /// </summary> /// <param name="keys">缓存Key集合</param> /// <returns></returns> Task<IDictionary<string, object>> GetAllAsync(IEnumerable<string> keys); /// <summary> /// 修改缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <returns></returns> bool Replace(string key, object value); /// <summary> /// 修改缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <returns></returns> Task<bool> ReplaceAsync(string key, object value); /// <summary> /// 修改缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <param name="expiresSliding">滑动过期时长（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <param name="expiressAbsoulte">绝对过期时长</param> /// <returns></returns> bool Replace(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte); /// <summary> /// 修改缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <param name="expiresSliding">滑动过期时长（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <param name="expiressAbsoulte">绝对过期时长</param> /// <returns></returns> Task<bool> ReplaceAsync(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte); /// <summary> /// 修改缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <param name="expiresIn">缓存时长</param> /// <param name="isSliding">是否滑动过期（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <returns></returns> bool Replace(string key, object value, TimeSpan expiresIn, bool isSliding = false); /// <summary> /// 修改缓存（异步方式） /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <param name="expiresIn">缓存时长</param> /// <param name="isSliding">是否滑动过期（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <returns></returns> Task<bool> ReplaceAsync(string key, object value, TimeSpan expiresIn, bool isSliding = false); } } |
然后，在增加实现类之前，先引入Redis的依赖项：
选择Microsoft.Extensions.Caching.Redis，版本选择2.1.2，安装一下。
在Services\Impl目录增加Redis的缓存实现类RedisCacheService：
| using Microsoft.Extensions.Caching.Redis; using Newtonsoft.Json; using StackExchange.Redis; using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ChainStoreAPI.Services.Impl { public class RedisCacheService : ICacheService { protected IDatabase _cache; private ConnectionMultiplexer _connection; private readonly string _instance; /// <summary> /// 构造函数 /// </summary> /// <param name="options"></param> /// <param name="database"></param> public RedisCacheService(RedisCacheOptions options, int database = 0) { _connection = ConnectionMultiplexer.Connect(options.Configuration); _cache = _connection.GetDatabase(database); _instance = options.InstanceName; } /// <summary> /// 为Key添加实例名 /// </summary> /// <param name="key"></param> /// <returns></returns> public string GetKeyForRedis(string key) { return _instance + ":" + key; } #region 验证缓存项是否存在 /// <summary> /// 验证缓存项是否存在 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> public bool Exists(string key) { if (key == null) { throw new ArgumentNullException(nameof(key)); } return _cache.KeyExists(GetKeyForRedis(key)); } public async Task<bool> ExistsAsync(string key) { bool result = await Task.Run(() => Exists(key)); return result; } #endregion #region 添加缓存 /// <summary> /// 添加缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <returns></returns> public bool Add(string key, object value) { if (key == null) { throw new ArgumentNullException(nameof(key)); } return _cache.StringSet(GetKeyForRedis(key), Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(value))); } /// <summary> /// 添加缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <param name="expiresSliding">滑动过期时长（如果在过期时间内有操作，则以当前时间点延长过期时间,Redis中无效）</param> /// <param name="expiressAbsoulte">绝对过期时长</param> /// <returns></returns> public bool Add(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte) { if (key == null) { throw new ArgumentNullException(nameof(key)); } return _cache.StringSet(GetKeyForRedis(key), Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(value)), expiressAbsoulte); } /// <summary> /// 添加缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">缓存Value</param> /// <param name="expiresIn">缓存时长</param> /// <param name="isSliding">是否滑动过期（如果在过期时间内有操作，则以当前时间点延长过期时间,Redis中无效）</param> /// <returns></returns> public bool Add(string key, object value, TimeSpan expiresIn, bool isSliding = false) { if (key == null) { throw new ArgumentNullException(nameof(key)); } return _cache.StringSet(GetKeyForRedis(key), Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(value)), expiresIn); } public async Task<bool> AddAsync(string key, object value) { bool result = await Task.Run(() => Add(key, value)); return result; } public async Task<bool> AddAsync(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte) { bool result = await Task.Run(() => Add(key, value, expiresSliding, expiressAbsoulte)); return result; } public async Task<bool> AddAsync(string key, object value, TimeSpan expiresIn, bool isSliding = false) { bool result = await Task.Run(() => Add(key, value, expiresIn, isSliding)); return result; } #endregion #region 删除缓存 /// <summary> /// 删除缓存 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> public bool Remove(string key) { if (key == null) { throw new ArgumentNullException(nameof(key)); } return _cache.KeyDelete(GetKeyForRedis(key)); } /// <summary> /// 批量删除缓存 /// </summary> /// <param name="key">缓存Key集合</param> /// <returns></returns> public void RemoveAll(IEnumerable<string> keys) { if (keys == null) { throw new ArgumentNullException(nameof(keys)); } keys.ToList().ForEach(item => Remove(item)); } public async Task<bool> RemoveAsync(string key) { bool result = await Task.Run(() => Remove(key)); return result; } public async Task RemoveAllAsync(IEnumerable<string> keys) { await Task.Run(() => RemoveAll(keys)); } #endregion #region 获取缓存 /// <summary> /// 获取缓存 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> public T Get<T>(string key) where T : class { if (key == null) { throw new ArgumentNullException(nameof(key)); } var value = _cache.StringGet(GetKeyForRedis(key)); if (!value.HasValue) { return default(T); } return JsonConvert.DeserializeObject<T>(value); } /// <summary> /// 获取缓存 /// </summary> /// <param name="key">缓存Key</param> /// <returns></returns> public object Get(string key) { if (key == null) { throw new ArgumentNullException(nameof(key)); } var value = _cache.StringGet(GetKeyForRedis(key)); if (!value.HasValue) { return null; } return JsonConvert.DeserializeObject(value); } /// <summary> /// 获取缓存集合 /// </summary> /// <param name="keys">缓存Key集合</param> /// <returns></returns> public IDictionary<string, object> GetAll(IEnumerable<string> keys) { if (keys == null) { throw new ArgumentNullException(nameof(keys)); } var dict = new Dictionary<string, object>(); keys.ToList().ForEach(item => dict.Add(item, Get(GetKeyForRedis(item)))); return dict; } public async Task<T> GetAsync<T>(string key) where T : class { T result = await Task.Run(() => Get(key)) as T; return result; } public async Task<object> GetAsync(string key) { object result = await Task.Run(() => Get(key)); return result; } public async Task<IDictionary<string, object>> GetAllAsync(IEnumerable<string> keys) { IDictionary<string, object> result = await Task.Run(() => GetAll(keys)); return result; } #endregion #region 修改缓存 /// <summary> /// 修改缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <returns></returns> public bool Replace(string key, object value) { if (key == null) { throw new ArgumentNullException(nameof(key)); } if (Exists(key)) if (!Remove(key)) return false; return Add(key, value); } /// <summary> /// 修改缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <param name="expiresSliding">滑动过期时长（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <param name="expiressAbsoulte">绝对过期时长</param> /// <returns></returns> public bool Replace(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte) { if (key == null) { throw new ArgumentNullException(nameof(key)); } if (Exists(key)) if (!Remove(key)) return false; return Add(key, value, expiresSliding, expiressAbsoulte); } /// <summary> /// 修改缓存 /// </summary> /// <param name="key">缓存Key</param> /// <param name="value">新的缓存Value</param> /// <param name="expiresIn">缓存时长</param> /// <param name="isSliding">是否滑动过期（如果在过期时间内有操作，则以当前时间点延长过期时间）</param> /// <returns></returns> public bool Replace(string key, object value, TimeSpan expiresIn, bool isSliding = false) { if (key == null) { throw new ArgumentNullException(nameof(key)); } if (Exists(key)) if (!Remove(key)) return false; return Add(key, value, expiresIn, isSliding); } public async Task<bool> ReplaceAsync(string key, object value) { bool result = await Task.Run(() => Replace(key, value)); return result; } public async Task<bool> ReplaceAsync(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte) { bool result = await Task.Run(() => Replace(key, value, expiresSliding, expiressAbsoulte)); return result; } public async Task<bool> ReplaceAsync(string key, object value, TimeSpan expiresIn, bool isSliding = false) { bool result = await Task.Run(() => Replace(key, value, expiresIn, isSliding)); return result; } #endregion /// <summary> /// 释放 /// </summary> public void Dispose() { if (_connection != null) _connection.Dispose(); GC.SuppressFinalize(this); } } } |
在配置文件appsettings.json中加入Redis的链接字符串：
| "RedisConnectionString": "127.0.0.1:6379" |
然后打开Startup.cs，引入缓存服务类：
当然，现在我们需要安装好Redis并启动：
运行run.bat即可：
我们将控制器TestController.cs重命名为MemberController.cs：
再新增测试控制器，将来我们的测试代码都在这里面实现：
我们只保留Get方法，其他全删除：
修改BaseController，加入缓存支持：
这样，我们就可以在所有继承BaseController的控制器中使用缓存了。
修改MemberController和TestController的构造函数：
下面我们在测试控制器中写代码测试一下缓存的写入和读取：
| // GET: api/Test [HttpGet] public ResultInfo Get() { cache.Add("test", "这是一个测试字符串"); string value = cache.Get<string>("test"); return new ResultInfo() { Code = "0", Message = "成功", Data = value }; } |
运行看一下效果：
打开RedisDesktopManager看一下Redis数据库中是否写入：
