add CacheKeyAccessor implementation

Author: stratosblue

package.props

@@ -6,7 +6,7 @@
 
   <!--Package Info-->
   <PropertyGroup>
-    <VersionPrefix>2.1.0</VersionPrefix>
+    <VersionPrefix>2.2.0</VersionPrefix>
     <!--<VersionSuffix>beta-05</VersionSuffix>-->
 
     <Description>The `asp.net core` server-side caching component implemented based on `ResourceFilter` and `ActionFilter`; 基于`ResourceFilter`和`ActionFilter`实现的`asp.net core`服务端缓存组件</Description>

readme.md

@@ -324,3 +324,13 @@ app.EnableResponseCachingDiagnosticLogger();
 ```
 
 如上配置后，内部将订阅相关`Diagnostic`，并将事件信息使用`ILogger`输出。
+
+-------
+
+## 其它
+
+### 1. 启用 `CacheKeyAccessor` 在代码中访问当前请求的 `cache key`
+```C#
+services.AddCaching()
+        .EnableCacheKeyAccessor(); //启用 CacheKeyAccessor ，从DI中获取 ICacheKeyAccessor 以访问当前请求的 `cache key`
+```

src/Cuture.AspNetCore.ResponseCaching/CacheKey/Builders/QueryKeysCacheKeyBuilder.cs

@@ -49,7 +49,7 @@ public override ValueTask<string> BuildAsync(FilterContext filterContext, String
                 char[]? buffer = null;
                 try
                 {
-                    buffer = ArrayPool<char>.Shared.Rent(queryString.Value!.Length);
+                    buffer = ArrayPool<char>.Shared.Rent(queryString.Value!.Length + 1);
                     var length = QueryStringOrderUtil.Order(queryString, buffer);
                     keyBuilder.Append(CombineChar);
                     keyBuilder.Append(buffer, 0, length);

src/Cuture.AspNetCore.ResponseCaching/CacheKey/Generators/FullPathAndQueryCacheKeyGenerator.cs

@@ -34,7 +34,7 @@ public ValueTask<string> GenerateKeyAsync(FilterContext filterContext)
         try
         {
             var path = pathValue.Value;
-            buffer = ArrayPool<char>.Shared.Rent(method.Length + path.Length + queryString.Value!.Length);
+            buffer = ArrayPool<char>.Shared.Rent(method.Length + path.Length + queryString.Value!.Length + 1);
 
             var span = buffer.AsSpan();
             method.CopyTo(span);

src/Cuture.AspNetCore.ResponseCaching/CacheKeyAccessor.cs

@@ -0,0 +1,31 @@
+namespace Cuture.AspNetCore.ResponseCaching;
+
+/// <summary>
+/// 缓存Key访问器
+/// </summary>
+public interface ICacheKeyAccessor
+{
+    #region Public 属性
+
+    /// <summary>
+    /// 缓存key
+    /// </summary>
+    string? Key { get; }
+
+    #endregion Public 属性
+}
+
+internal sealed class CacheKeyAccessor : ICacheKeyAccessor
+{
+    #region Private 字段
+
+    private static readonly AsyncLocal<string?> s_asyncLocalCacheKey = new();
+
+    #endregion Private 字段
+
+    #region Public 属性
+
+    public string? Key { get => s_asyncLocalCacheKey.Value; set => s_asyncLocalCacheKey.Value = value; }
+
+    #endregion Public 属性
+}

src/Cuture.AspNetCore.ResponseCaching/Context/ResponseCachingContext.cs

@@ -81,6 +81,11 @@ public class ResponseCachingContext : IDisposable
     /// </summary>
     public IResponseCache ResponseCache { get; }
 
+    /// <summary>
+    /// 构建时使用的 <see cref="IServiceProvider"/>
+    /// </summary>
+    public IServiceProvider ServiceProvider { get; }
+
     #endregion Public 属性
 
     #region Protected 构造函数
@@ -107,13 +112,15 @@ protected ResponseCachingContext()
     /// <param name="options"></param>
     /// <param name="interceptorAggregator"></param>
     /// <param name="dumpStreamCapacity"></param>
+    /// <param name="serviceProvider"></param>
     public ResponseCachingContext(EndpointMetadataCollection metadatas,
                                   ICacheKeyGenerator cacheKeyGenerator,
                                   IResponseCache responseCache,
                                   IResponseCacheDeterminer cacheDeterminer,
                                   ResponseCachingOptions options,
                                   InterceptorAggregator interceptorAggregator,
-                                  int dumpStreamCapacity)
+                                  int dumpStreamCapacity,
+                                  IServiceProvider serviceProvider)
     {
         ArgumentNullException.ThrowIfNull(metadatas);
 
@@ -131,13 +138,16 @@ public ResponseCachingContext(EndpointMetadataCollection metadatas,
         LockMillisecondsTimeout = Checks.ThrowIfLockMillisecondsTimeoutInvalid(executingLockMetadata?.LockMillisecondsTimeout ?? options.DefaultLockMillisecondsTimeout).Value;
 
         Interceptors = interceptorAggregator;
+
         DumpStreamCapacity = Checks.ThrowIfDumpStreamInitialCapacityTooSmall(dumpStreamCapacity, nameof(dumpStreamCapacity));
 
         OnCannotExecutionThroughLock = options.OnCannotExecutionThroughLock ?? DefaultExecutionLockTimeoutFallback.SetStatus429;
         OnExecutionLockTimeout = executingLockMetadata?.OnExecutionLockTimeout
                                  ?? options.OnExecutionLockTimeoutFallback
                                  ?? DefaultExecutionLockTimeoutFallback.SetStatus429;
 
+        ServiceProvider = serviceProvider;
+
         TMetadata? Metadata<TMetadata>() where TMetadata : class => metadatas.GetMetadata<TMetadata>();
         TMetadata RequiredMetadata<TMetadata>() where TMetadata : class => metadatas.RequiredMetadata<TMetadata>();
     }

src/Cuture.AspNetCore.ResponseCaching/DefaultResponseCachingFilterBuilder.cs

@@ -68,7 +68,8 @@ public IFilterMetadata CreateFilter(IServiceProvider serviceProvider)
                                                                 cacheDeterminer: cacheDeterminer,
                                                                 options: buildContext.Options,
                                                                 interceptorAggregator: interceptorAggregator,
-                                                                dumpStreamCapacity: dumpStreamCapacity);
+                                                                dumpStreamCapacity: dumpStreamCapacity,
+                                                                serviceProvider: serviceProvider);
         return filterType switch
         {
             FilterType.Resource => executingLockPool is null

src/Cuture.AspNetCore.ResponseCaching/Filters/CacheFilterBase.cs

@@ -1,11 +1,13 @@
-using System.Runtime.CompilerServices;
+using System.Diagnostics.CodeAnalysis;
+using System.Runtime.CompilerServices;
 
 using Cuture.AspNetCore.ResponseCaching.Diagnostics;
 using Cuture.AspNetCore.ResponseCaching.Interceptors;
 using Cuture.AspNetCore.ResponseCaching.ResponseCaches;
 
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Filters;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 
 namespace Cuture.AspNetCore.ResponseCaching.Filters;
@@ -19,6 +21,8 @@ public abstract class CacheFilterBase<TFilterExecutingContext>
 {
     #region Private 字段
 
+    private readonly CacheKeyAccessor? _cacheKeyAccessor;
+
     private readonly CachingDiagnosticsAccessor _cachingDiagnosticsAccessor;
 
     private readonly OnCacheStoringDelegate<ActionContext> _onCacheStoringDelegate;
@@ -27,6 +31,13 @@ public abstract class CacheFilterBase<TFilterExecutingContext>
 
     #endregion Private 字段
 
+    #region Private 属性
+
+    [MemberNotNullWhen(true, nameof(_cacheKeyAccessor))]
+    private bool NeedSetCacheKeyAccessor { get; }
+
+    #endregion Private 属性
+
     #region Protected 属性
 
     /// <inheritdoc cref="Diagnostics.CachingDiagnostics"/>
@@ -61,6 +72,11 @@ public CacheFilterBase(ResponseCachingContext context, CachingDiagnosticsAccesso
         CachingDiagnostics = _cachingDiagnosticsAccessor.CachingDiagnostics;
         Logger = CachingDiagnostics.Logger;
         ResponseCache = Context.ResponseCache;
+
+        _cacheKeyAccessor = context.ServiceProvider.GetService<CacheKeyAccessor>();
+
+        NeedSetCacheKeyAccessor = _cacheKeyAccessor is not null;
+
         _onCacheStoringDelegate = InternalStoreCacheAsync;
     }
 
@@ -169,6 +185,18 @@ protected Task<bool> WriteCacheToResponseWithInterceptorAsync(ActionContext cont
 
     #endregion Response with cache
 
+    /// <summary>
+    /// 设置 <see cref="ICacheKeyAccessor"/>
+    /// </summary>
+    /// <param name="cacheKey"></param>
+    protected void SetCacheKeyAccessor(string cacheKey)
+    {
+        if (NeedSetCacheKeyAccessor)
+        {
+            _cacheKeyAccessor.Key = cacheKey;
+        }
+    }
+
     #endregion Protected 方法
 
     #region Dispose

src/Cuture.AspNetCore.ResponseCaching/Filters/DefaultActionCacheFilter.cs

@@ -45,6 +45,8 @@ public async Task OnActionExecutionAsync(ActionExecutingContext executingContext
         var key = (await Context.KeyGenerator.GenerateKeyAsync(executingContext)).ToLowerInvariant();
         CachingDiagnostics.CacheKeyGenerated(executingContext, key, Context.KeyGenerator, Context);
 
+        SetCacheKeyAccessor(key);
+
         if (key.Length > Context.MaxCacheKeyLength)
         {
             CachingDiagnostics.CacheKeyTooLong(key, Context.MaxCacheKeyLength, executingContext, Context);

src/Cuture.AspNetCore.ResponseCaching/Filters/DefaultResourceCacheFilter.cs

@@ -49,6 +49,8 @@ private async Task InternalOnResourceExecutionAsync(ResourceExecutingContext exe
             var key = (await Context.KeyGenerator.GenerateKeyAsync(executingContext)).ToLowerInvariant();
             cachingDiagnostics.CacheKeyGenerated(executingContext, key, Context.KeyGenerator, Context);
 
+            SetCacheKeyAccessor(key);
+
             if (key.Length > Context.MaxCacheKeyLength)
             {
                 cachingDiagnostics.CacheKeyTooLong(key, Context.MaxCacheKeyLength, executingContext, Context);