Getting 405 on a method which is using Cache

ServiceStack Caching
1

I have written a code like follows utilizing ToOptimizedResultUsingCacheAsync method, but I am getting 405 status code. And getting a error saying

Serializing Task’s is not supported. Did you forget to await it?

I have added the await on my method as well.

public async Task<object> GetAsync(RequestDTO request)
{
    return await Request.ToOptimizedResultUsingCacheAsync(CacheAsync,Defaults.CacheKey, TimeSpan.FromSeconds(60),
    async () =>
     {
              var result = await GetResultAsync();
             // Processing the result adding some filteration and pagination to it.
             
             return new ResponseDTO
             {
                     Response = resultToReturn,
                     // Extra details regarding the result and the filteration or anything which has been applied.
             }
     }
}
2

The factory method isn’t async, ToOptimizedResultUsingCacheAsync is only used for invoking CacheAsync async APIs.

You’d need to use a different implementation of:

That lets you await the factory method, something like:

public static async Task<object> ToOptimizedResultUsingCacheAsync<T>(
    this IRequest req, ICacheClientAsync cacheClient, string cacheKey,
    TimeSpan? expireCacheIn, Func<Task<T>> factoryFn, CancellationToken token=default)
{
    var cacheResult = await cacheClient.ResolveFromCacheAsync(cacheKey, req, token).ConfigAwait();
    if (cacheResult != null)
        return cacheResult;

    var responseDto = await factoryFn().ConfigAwait();
    cacheResult = await cacheClient.CacheAsync(cacheKey, responseDto, req, expireCacheIn, token).ConfigAwait();
    return cacheResult;
}

Which I’ve also just added. This change is available from v5.8.3+ that’s now available in pre-release packages.

3

Ahh thanks for the clarification about the methods.
I will use the method you suggested.

One more thing regarding the cache attribute.

If I use [CacheResponse(Duration = 60)] attribute on my method it will cache its response.
This is working fine but what if I have to invalidate the response which is cached by the above attribute how will I do that?

As we are not specifying any key in the attribute nor we have any overload that supports specifying the key.

4

You can’t easily invalidate a time based cache. If you need precise control you’d need to implement it in your API.

5

I see, thanks @mythz

6 
var cacheObj = await CacheAsync.ResolveFromCacheAsync(Defaults.ResponseCacheKey, Request);
if (cacheObj != null)
    return cacheObj;
// Rest of the method to get from DB
// Setting the cache
 await CacheAsync.CacheAsync(Defaults.ResponseCacheKey, responseToReturn, Request, TimeSpan.FromMinutes(Defaults.CacheExpiryInMinutes));

I did use this method as you suggested and its working properly for me, contents are getting cached I am getting 200 and 304 as and when required.

But I am unable to write the tests for it using NUnit Framework.
I am unable to Mock the IRequest and it is getting passed as null so all of the tests are failing.

 var cache = appHost.Container.Resolve<ICacheClientAsync>();
 var mockRequest = new Mock<IRequest>();
 var mockServices = new Mock<Services>();

mockServices.Setup(s => s.CacheAsync.CacheAsync(Defaults.ResponseCacheKey, new Response { }, mockRequest.Object, TimeSpan.FromMinutes(Defaults.CacheExpiryInMinutes), CancellationToken.None).AsTaskResult());


 var Services = mockSystemServices.Object;
 // Explicitly specify all arguments, avoid relying on optional parameters

 var response = await Services.GetAsync(new List());

 Assert.IsInstanceOf<Response>(response);
 var Response = response as Response;
 Assert.NotNull(Response);
 Assert.AreEqual(3, Response.Items.Count);
 Assert.AreEqual("A", Response.Items[0].Name);
 Assert.AreEqual("B", Response.Items[1].Name);
 Assert.AreEqual("C", Response.Items[2].Name);

I am doing this but the IRequest is getting passed as null always.

I am having the OneTimeSetUp() as well in which I am intializing the DB in memory and resolving the dependancy.

7

See testing docs for how to test ServiceStack classes which require an initialized AppHost.

I personally never use Mocks, if I need to stub an IRequest context I’d use the memory BasicHttpRequest or BasicRequest classes.