Prevent Caching in ASP.NET MVC for specific actions using an attribute
I have an ASP.NET MVC 3 application. This application requests records through JQuery. JQuery calls back to a controller action that returns results in JSON format. I have not been able to prove this, but I'm concerned that my data may be getting cached.
I only want the caching to be applied to specific actions, not for all actions.
Is there an attribute that I can put on an action to ensure that the data does not get cached? If not, how do I ensure that the browser gets a new set of records each time, instead of a cached set?
To ensure that JQuery isn't caching the results, on your ajax methods, put the following:
$.ajax({
cache: false
//rest of your ajax setup
});
Or to prevent caching in MVC, we created our own attribute, you could do the same. Here's our code:
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
public sealed class NoCacheAttribute : ActionFilterAttribute
{
public override void OnResultExecuting(ResultExecutingContext filterContext)
{
filterContext.HttpContext.Response.Cache.SetExpires(DateTime.UtcNow.AddDays(-1));
filterContext.HttpContext.Response.Cache.SetValidUntilExpires(false);
filterContext.HttpContext.Response.Cache.SetRevalidation(HttpCacheRevalidation.AllCaches);
filterContext.HttpContext.Response.Cache.SetCacheability(HttpCacheability.NoCache);
filterContext.HttpContext.Response.Cache.SetNoStore();
base.OnResultExecuting(filterContext);
}
}
Then just decorate your controller with [NoCache] . OR to do it for all you could just put the attribute on the class of the base class that you inherit your controllers from (if you have one) like we have here:
[NoCache]
public class ControllerBase : Controller, IControllerBase
You can also decorate some of the actions with this attribute if you need them to be non-cacheable, instead of decorating the whole controller.
If your class or action didn't have NoCache when it was rendered in your browser and you want to check it's working, remember that after compiling the changes you need to do a "hard refresh" (Ctrl+F5) in your browser. Until you do so, your browser will keep the old cached version, and won't refresh it with a "normal refresh" (F5).
You can use the built in cache attribute to prevent caching.
For .net Framework: [OutputCache(NoStore = true, Duration = 0)]
For .net Core: [ResponseCache(NoStore = true, Duration = 0)]
Be aware that it is impossible to force the browser to disable caching. The best you can do is provide suggestions that most browsers will honor, usually in the form of headers or meta tags. This decorator attribute will disable server caching and also add this header: Cache-Control: public, no-store, max-age=0 . It does not add meta tags. If desired, those can be added manually in the view.
Additionally, JQuery and other client frameworks will attempt to trick the browser into not using it's cached version of a resource by adding stuff to the url, like a timestamp or GUID. This is effective in making the browser ask for the resource again but doesn't really prevent caching.
On a final note. You should be aware that resources can also be cached in between the server and client. ISP's, proxies, and other network devices also cache resources and they often use internal rules without looking at the actual resource. There isn't much you can do about these. The good news is that they typically cache for shorter time frames, like seconds or minutes.
All you need is:
[OutputCache(Duration=0)]
public JsonResult MyAction(
or, if you want to disable it for an entire Controller:
[OutputCache(Duration=0)]
public class MyController
Despite the debate in comments here, this is enough to disable browser caching - this causes ASP.Net to emit response headers that tell the browser the document expires immediately:
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