How to invalidate Web API cache from another Controller(ASP.NET Web API CacheOutput Library)

Question

I have used ASP.NET Web API CacheOutput Library for my asp.net project for web API and it working fine, but have another controller from where I have a POST method and I would like to invalidate my cache from that controller.

[AutoInvalidateCacheOutput]
public class EmployeeApiController : ApiController
{ 
    [CacheOutput(ClientTimeSpan = 100, ServerTimeSpan = 100)]
    public IEnumerable<DropDown> GetData()
    {
        //Code here
    }
}


public class EmployeesController : BaseController
{
    [HttpPost]
    public ActionResult CreateEmployee (EmployeeEntity empInfo)
    {
        //Code Here
    }
}

I would like to invalidate Employees Cache when there is add\update in employee controller.

I want Cache, but just would like to invalidate when there is change in employee controller — Suresh, Dec 11 '14 at 08:06

score 13 · Accepted Answer · edited May 31 '22 at 02:45

It is little tricky, but you can get it in this way:

1. On your WebApiConfig:

// Registering the IApiOutputCache.    
var cacheConfig = config.CacheOutputConfiguration();
cacheConfig.RegisterCacheOutputProvider(() => new MemoryCacheDefault());

We will need of it to get the IApiOutputCache from GlobalConfiguration.Configuration.Properties, if we let the default properties' setup happen the property with the IApiOutputCache won't exists on MVC BaseController request.

2. Create a WebApiCacheHelper class:

using System;
using System.Linq.Expressions;
using System.Web.Http;
using WebApi.OutputCache.Core.Cache;
using WebApi.OutputCache.V2;

namespace MideaCarrier.Bss.WebApi.Controllers
{
    public static class WebApiCacheHelper
    {
        public static void InvalidateCache<T, U>(Expression<Func<T, U>> expression)
        {
            var config = GlobalConfiguration.Configuration;

            // Gets the cache key.
            var outputConfig = config.CacheOutputConfiguration();
            var cacheKey = outputConfig.MakeBaseCachekey(expression);

            // Remove from cache.
            var cache = (config.Properties[typeof(IApiOutputCache)] as Func<IApiOutputCache>)();
            cache.RemoveStartsWith(cacheKey);
        }
    }
}

3. Then, call it from your EmployeesController.CreateEmployee action:

public class EmployeesController : BaseController
{
    [HttpPost]
    public ActionResult CreateEmployee (EmployeeEntity empInfo)
    {
        // your action code Here.
        WebApiCacheHelper.InvalidateCache((EmployeeApiController t) => t.GetData());
    }
}

Thanks, but i am using ASP.Net 4.0 and WebApi.OutputCache.V2 is available only in ASP.net 4.5 do you have any other suggestion for work with ASP.Net 4.0? or i have to upgrade my solution to asp.net 4.5 — Suresh, Dec 11 '14 at 13:12
I don't know, I've never used WebApi.OutputCache with ASP .NET 4.0. — giacomelli, Dec 11 '14 at 13:22
Seems your solution will work for 4.5 as it doesn't solved my problem but accepting as answer hope that will help to others. — Suresh, Dec 15 '14 at 17:05

How to invalidate Web API cache from another Controller(ASP.NET Web API CacheOutput Library)

1 Answers1