[Suggestion] Exclude caching based on http header value

[Hashemalrifai]

Example: Ignore caching if Accept-Languages value is different.

[nate-red]

You simply write a new CacheKeyGenerator by overriding MakeCacheKey in the DefaultCacheKeyGenerator class.

The function takes the context as argument and returns a string key identifying the cached ressource.

Then you simply concat the default key to the Accept-Language by accessing the context that is passed in the arguments.

Have fun.

[Hashemalrifai]

Thanks, I will try it 👍

[ericlundmark]

Are trying to achieve the same thing have written the following cachekey

var v = base.MakeCacheKey(context, mediaType, excludeQueryString);
return context.Request.Headers.Accept + v;

but it does not seem to work when testing with postman. I have the following configuration

config.CacheOutputConfiguration().RegisterCacheOutputProvider(() => new MemoryCacheDefault());
config.CacheOutputConfiguration().RegisterDefaultCacheKeyGeneratorProvider(() => new AcceptHeaderKeyGenerator());

[nate-red]

Do you really want to cache using the Accept header ? Not the AcceptLanguage ?

Because that's two different things....

[ericlundmark]

Yep, if someone requests the resource in a different format using the accept header I do not want to return the same data. E.g. someone requests an image/tiff and then requests an image/png I want to return different data, not the cached image/tiff.

[nate-red]

Try appending this on the controller's function that you are calling :
[CacheOutput(CacheKeyGenerator = typeof(AcceptHeaderKeyGenerator))]

[ericlundmark]

Seems to do the trick! but I expected it to be enough to configure it as the default CacheKeyGeneratorProvider? Thanks anyway :)

[Korayem]

Can you merge this PR #126 to have this functionality out of the box

[GithubMaastricht]

Dear readers, how to enable or use "PerUserCacheKeyGenerator" ?

1) I have implemented

public class PerUserCacheKeyGenerator : DefaultCacheKeyGenerator
{ public override string MakeCacheKey
{ .....

2) and decorated the Controllers with:
[CacheOutput(ClientTimeSpan = 259200, ServerTimeSpan = 259200, CacheKeyGenerator = typeof(PerUserCacheKeyGenerator))]

3) and registered the PerUserCacheKeyGenerator class in WebApiConfig.cs with:

config.CacheOutputConfiguration().RegisterCacheOutputProvider(() => new MemoryCacheDefault());
config.CacheOutputConfiguration().RegisterDefaultCacheKeyGeneratorProvider(() => new PerUserCacheKeyGenerator());

But still the class PerUserCacheKeyGenerator is not used when requesting the controllers actions....

Any help?