public async Task RecalculatesCachedValueAfterTimeHasPassed_DespiteOfCachedValueWasRetrieved_WhenAbsoluteExpirationIsSpecifiedAsync()
{
// Arrange - Setup ApplicationCache, Mock & put initial cache value that will expire in 100 milliseconds
using var cache = new ApplicationCache();
const string cacheName = "CacheTests-AbsoluteExp3";
const string initialCacheValue = "Message-0";
var functionMock = new Mock <Func <Task <string> > >();
functionMock.Setup(x => x()).Returns(Task.FromResult(initialCacheValue));
await cache.GetOrAddWithAbsoluteExpirationAsync(cacheName, functionMock.Object, CacheDuration).ConfigureAwait(false);
await Task.Delay(LessThanCacheDuration).ConfigureAwait(false);
await cache.GetOrAddWithAbsoluteExpirationAsync(cacheName, functionMock.Object, CacheDuration).ConfigureAwait(false);
functionMock.Invocations.Clear();
await Task.Delay(AdditionalLessThanCacheDuration).ConfigureAwait(false); // delay for another 70 milliseconds so the total delay is 120 (50 + 70) milliseconds since the 1st cache call
// Act - put new cache value and get the cached value
var newCacheValue = "Message-1";
functionMock.Setup(x => x()).Returns(Task.FromResult(newCacheValue));
var cachedValue = await cache.GetOrAddWithAbsoluteExpirationAsync(cacheName, functionMock.Object, CacheDuration).ConfigureAwait(false);
// Assert that the cached value has new cache value because the cache has expired since the 1st cache call
Assert.That(cachedValue, Is.EqualTo(newCacheValue));
functionMock.Verify(x => x(), Times.Once);
}
public async Task UsesCachedValueUntilTimeHasPassed_WhenAbsoluteExpirationIsSpecifiedAsync()
{
// Arrange - Setup ApplicationCache, Mock & put initial cache value that will expire in 100 milliseconds
using var cache = new ApplicationCache();
const string cacheName = "CacheTests-AbsoluteExp1";
const string initialCacheValue = "Message-0";
var functionMock = new Mock <Func <Task <string> > >();
functionMock.Setup(x => x()).Returns(Task.FromResult(initialCacheValue));
await cache.GetOrAddWithAbsoluteExpirationAsync(cacheName, functionMock.Object, CacheDuration).ConfigureAwait(false);
functionMock.Invocations.Clear();
await Task.Delay(LessThanCacheDuration).ConfigureAwait(false);
// Act - put new cache value and get cached value
var newCacheValue = "Message-1";
functionMock.Setup(x => x()).Returns(Task.FromResult(newCacheValue));
var cachedValue = await cache.GetOrAddWithAbsoluteExpirationAsync(cacheName, functionMock.Object, CacheDuration).ConfigureAwait(false);
// Assert that the cached value still holds the initial value because the cache has not expired
Assert.That(cachedValue, Is.EqualTo(initialCacheValue));
functionMock.Verify(x => x(), Times.Never);
}