/// <summary>
/// Get or create cache value
/// </summary>
/// <typeparam name="T">Type of the value cached or to be cached</typeparam>
/// <param name="cacheKey">Key of the cache</param>
/// <param name="valueProviderFunc">Value provider function in case the value is not in the cache</param>
/// <returns>The requested cache value</returns>
public T GetOrCreateValue <T>(string cacheKey, Func <T> valueProviderFunc)
{
// Try to get cache value from local cache
var localCacheValue = _inMemoryCacheProvider.Get <T>(cacheKey);
if (localCacheValue != null)
{
// Touch distributed cache (async way without waiting for the result) to mark usage but otherwise return the local value
_ = _distributedCacheProvider.GetAsync <T>(cacheKey);
return(localCacheValue);
}
// Try to get cache value from the distributed cache if not found in the local one
var distributedCacheValue = _distributedCacheProvider.Get <T>(cacheKey);
if (distributedCacheValue != null)
{
// "Download" value to local cache
_inMemoryCacheProvider.Set(cacheKey, distributedCacheValue);
return(distributedCacheValue);
}
// Cache not found in any of the cache providers so obtain it using the given provider function
var cacheValueToSet = valueProviderFunc.Invoke();
// Fill in cache
_inMemoryCacheProvider.Set(cacheKey, cacheValueToSet);
_distributedCacheProvider.Set(cacheKey, cacheValueToSet);
// Return the obtained value
return(cacheValueToSet);
}
public async void GetAsync()
{
// Arrange
string cacheKey = "Unit-Test-Cache";
var innerCacheValue = JsonSerializer.SerializeToUtf8Bytes("MockCacheValue");
_innerCacheMock.Setup(ic => ic.GetAsync(cacheKey, It.IsAny <CancellationToken>())).Returns(Task.FromResult(innerCacheValue));
// Act
var obtainedCacheValue = await _cacheProvider.GetAsync <string>(cacheKey.ToString());
// Assert
_innerCacheMock.Verify(ic => ic.GetAsync(cacheKey, It.IsAny <CancellationToken>()));
Assert.Equal(JsonSerializer.Deserialize <string>(innerCacheValue), obtainedCacheValue);
}