ASP.NET MVC Unit Testing With HttpContextBase.Cache

9/6/2008 4:32:15 PM

Technologies

ASP.NET MVC
.NET Framework 3.5

I was trying to unit test a controller that made use of System.Web.Caching.Cache to store a chunk of data returned from the db that only needed to be fetched every 15 minutes or so. The test I was writing was to make sure that if the data was in the cache that it would be used instead of fetched. I thought this would be really straight forward:

Instantiate System.Web.Caching.Cache
Add my data to the cache
Add the cache object to my HttpContextBase stub
Set the stub on the controller
Run the controller action
Assert my returned data from the action

However, whenever I added items to the instantiated cache null reference exceptions would be thrown. After some reflector digging this is because the cache object is actually storing the data in an instance of System.Web.Caching.CacheInternal. ASP.net needs a thorough makeover . . .

After some googling I came across this great tip that showed how HttpRuntime.Cache properly instantiates CacheInternal. Problem solved.

   1:  Cache testCache = HttpRuntime.Cache;

Comments

HttpRuntime.Cache is fine, while HttpContext.Cache not work in test project, but is there any difference?

Thanks a lot! ;)

Thanks for information!

Thanks for this. You were the first search result in bing and my unit test worked on the first try!

Paul

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