Caching GET .NET Webservice Call in Client - Headers not being updated

Question

I am trying to cache a parameterized GET webservice call in ASP.NET 4.5/C#. I've tried all the options that I've read in StackOverflow, including setting the HttpCachePolicy, using CacheDuration attribute, but I always get Cache-Control :no-cache, Expired: -1, Pragma: no-cache and the call to the webservice returns 200 not 304 (Not modified).

The content is cached correctly on the server,but I want the cache headers to be updated as well so it won't even get to call to the server for a give amount of time which I specified in the cache.

I also tried this approach but it didn't work:

  HttpCachePolicy cache = HttpContext.Current.Response.Cache;
        cache.VaryByParams["*"] = true;
        cache.SetCacheability(HttpCacheability.Private);
        cache.SetExpires(DateTime.Now.AddSeconds((double)900));

        FieldInfo maxAgeField = cache.GetType().GetField(
            "_maxAge", BindingFlags.Instance | BindingFlags.NonPublic);
        maxAgeField.SetValue(cache, new TimeSpan(0, 0, 900));

and also tried:

 private void SetCachingPolicy()
    {
        HttpCachePolicy cache = HttpContext.Current.Response.Cache;
        cache.VaryByParams["*"] = true;
        cache.SetCacheability(HttpCacheability.Private);
        cache.SetExpires(DateTime.Now.AddSeconds((double)900));

        FieldInfo maxAgeField = cache.GetType().GetField(
            "_maxAge", BindingFlags.Instance | BindingFlags.NonPublic);
        maxAgeField.SetValue(cache, new TimeSpan(0, 0, 900));
    }

The caching code is applied within the web-service call Web Method.

I want the webservice call (which I call from jQuery/Ajax) to be cached in the client for a few seconds or minutes.

I am testing it in my local IIS 7.5 server on my Windows 7 computer, using Visual Studio as the dev platform. I am also using Chrome Network traffic to test the response headers.

Have you checked that you aren't setting headers in your local IIS? — ste-fu, Jan 15 '16 at 11:17
Try setting it to use local IIS and setting the cache headers in that maybe? — ste-fu, Jan 15 '16 at 11:34
Basically, you want to cache the results of the web service call at the client side, is that correct? — TejSoft, Jan 18 '16 at 23:32
Cache the result and still return 403 (Forbidden) from server? Why would you need the trip to the server when the results are cached at the client? — TejSoft, Jan 18 '16 at 23:55
Have a look at this SO answer. It discusses about the same problem: http://stackoverflow.com/questions/17287144/how-to-cache-net-web-api-requests-use-w-angularjs-http — TejSoft, Jan 20 '16 at 01:05
Have you tried setting the OutputCache https://msdn.microsoft.com/en-us/library/system.web.mvc.outputcacheattribute(v=vs.118).aspx on the controller? — ste-fu, Jan 20 '16 at 15:09

score 1 · Accepted Answer · answered Jan 20 '16 at 14:26

Can you just update your response Header with a CachePolicy, that might be a simple solution to alert the clients(browsers) to cache it for sometime.

response.Headers.CacheControl = new CacheControlHeaderValue()
{
      Public = false,
      MaxAge = new TimeSpan(0, 0, 900)
};

Caching GET .NET Webservice Call in Client - Headers not being updated

1 Answers1