.net core(.net 6) IResourceFilter 扩展缓存（IAsyncResourceFilter）

参考：.net core(.net 6) IResourceFilter 的基础使用（IAsyncResourceFilter） 

缓存：就是一个临时存储区域，以一个Key-value格式保存数据；key---保存数据的标识，也需要这个表示key才能获取缓存。

a 定义一个静态的键值对Dictionary作为临时存储区域

b 在API执行前（OnResourceExecuting）判断该请求是否存在缓存，若存在则直接返回缓存的数据终止action执行

c 在API执行后（OnResourceExecuted）此时说明没有缓存执行了action，就把计算结果存储到缓存内

扩展类:CustomCacheResourceFilterAttribute.cs

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;
using System;

namespace Demo02.Utility.Filters
{
    /// <summary>
    /// 自定义ResourceFilter扩展缓存
    /// </summary>
    public class CustomCacheResourceFilterAttribute : Attribute, IResourceFilter
    {
        private static Dictionary<string, Object> CacheDictionary = new Dictionary<string, object>();


        /// <summary>
        /// API执行后 执行
        /// </summary>
        /// <param name="context"></param>
        /// <exception cref="NotImplementedException"></exception>
        public void OnResourceExecuted(ResourceExecutedContext context)
        {
            //执行到这里说明之前没有缓存，并已执行了API，需要将该次数据处理的结果存储到缓存中
            string key = context.HttpContext.Request.Path;
            CacheDictionary[key] = context.Result;

           
        }

        /// <summary>
        /// API执行前 执行
        /// </summary>
        /// <param name="context"></param>
        /// <exception cref="NotImplementedException"></exception>
        public void OnResourceExecuting(ResourceExecutingContext context)
        {
            //将Url作为缓存标识符，相同url同一数据
            string key = context.HttpContext.Request.Path;//Url地址
            if(CacheDictionary.ContainsKey(key))
            {
                object oResult = CacheDictionary[key];
                IActionResult result = oResult as IActionResult;
                context.Result = result;//该变量相当于请求数据处理中的一个断路器，如果给Result值就会终止执行返回Result，如果没有赋值为null，就会继续往后执行。
            }
        }
    }
}

API action测试：

  
        /// <summary>
        /// GET AOP测试 ResourceFilter缓存
        /// </summary>
        /// <returns></returns>
        [HttpGet()]
        [Route("ResourceFilter/CustomCacheResourceFilter/{id:int}")]
        [CustomCacheResourceFilter]
        public IActionResult Get(int id)
        {
            return new JsonResult(new ApiResut<String>()
            {
                Success = true,
                Data = "AOP ResourceFilter 测试",
                Time = DateTime.Now.ToString()

            });
        }

测试结果：

IAsyncResourceFilter

CustomCacheAsyncResourceFilterAttribute 自定义AsyncResourceFilter标记类

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;
using System;

namespace Demo02.Utility.Filters
{
    /// <summary>
    /// 自定义AsyncResourceFilter标记类
    /// </summary>
    public class CustomCacheAsyncResourceFilterAttribute : Attribute, IAsyncResourceFilter
    {
        private static Dictionary<string, Object> CacheDictionary = new Dictionary<string, object>();

        /// <summary>
        /// API异步action 执行前后
        /// </summary>
        /// <param name="context"></param>
        /// <param name="next"></param>
        /// <returns></returns>
        public async Task OnResourceExecutionAsync(ResourceExecutingContext context, ResourceExecutionDelegate next)
        {
            //将Url作为缓存标识符，相同url同一数据
            string key = context.HttpContext.Request.Path;//Url地址
            if (CacheDictionary.ContainsKey(key))
            {
                object oResult = CacheDictionary[key];
                IActionResult result = oResult as IActionResult;
                context.Result = result;//该变量相当于请求数据处理中的一个断路器，如果给Result值就会终止执行返回Result，如果没有赋值为null，就会继续往后执行。
            }
            else
            {
               ResourceExecutedContext executedContext =  await next.Invoke();
                //执行到这里说明之前没有缓存，并已执行了API，需要将该次数据处理的结果存储到缓存中
                CacheDictionary[key] = executedContext.Result;
            }
          

        }
    }
}

API action测试

   /// <summary>
        /// GET AOP测试 ResourceFilter缓存异步
        /// </summary>
        /// <returns></returns>
        [HttpGet()]
        [Route("ResourceFilter/CustomCacheAsyncResourceFilter/{id:int}")]
        [CustomCacheAsyncResourceFilter]
        public IActionResult AsyncGet(int id)
        {
            return new JsonResult(new ApiResut<String>()
            {
                Success = true,
                Data = "AOP ResourceFilter 测试",
                Time = DateTime.Now.ToString()

            });
        }