public async Task <TCacheItem> AwaitCacheItem(LazyAwaitableCacheItem <TCacheItem> itemToAwait)
{
try
{
return(await itemToAwait.GetTask().ConfigureAwait(false));
}
catch (Exception ex)
{
itemToAwait.Reset();
throw ex;
}
}
/// <summary>
/// Gets or creates an item in the cache.
/// </summary>
/// <param name="key">The key under which the item is stored.</param>
/// <param name="itemFactory">A fsctory operation for creating the item.</param>
/// <returns>A Task representing the cache item.</returns>
public async Task <TCacheItem> GetOrCreateItem(
string key,
Func <Task <TCacheItem> > itemFactory,
TimeSpan?expiresAfter = null)
{
LazyAwaitableCacheItem <TCacheItem> cacheItem =
this.cache.GetOrAdd(
key,
new LazyAwaitableCacheItem <TCacheItem>(itemFactory));
this.OnItemAdd(this, new AddItemEventArgs(key, expiresAfter ?? this.expiresAfterOnDefault));
return(await this.awaitingStrategy.AwaitCacheItem(cacheItem));
}
/// <summary>
/// Loads a particular item out of the cache.
/// If under the supplied key no item is found,
/// default(TCacheItem) is retured.
/// </summary>
/// <param name="key">Specifies the key of the requested item.
/// Must not be null, whitespace or empty.</param>
/// <returns>A Task representing the requested item.</returns>
public async Task <TCacheItem> GetItem(string key)
{
if (String.IsNullOrWhiteSpace(key))
{
throw new ArgumentNullException(nameof(key));
}
LazyAwaitableCacheItem <TCacheItem> encachedValue = null;
Task <TCacheItem> cacheItemTask = null;
if (cache.TryGetValue(key, out encachedValue))
{
cacheItemTask = this.awaitingStrategy.AwaitCacheItem(encachedValue);
}
else
{
cacheItemTask = Task.FromResult <TCacheItem>(default(TCacheItem));
}
return(await cacheItemTask);
}
/// <summary>
/// Tries to remove an item from the cache.
/// </summary>
/// <param name="key">The of the item.</param>
/// <param name="removedCacheItem">References the cacheitem when removing succeeded.</param>
/// <returns>Returns true when removing succeeded. Otherwise false.</returns>
public bool TryRemove(
string key,
out LazyAwaitableCacheItem <TCacheItem> removedCacheItem)
{
return(this.cache.TryRemove(key, out removedCacheItem));
}
/// <summary>
///
/// </summary>
/// <param name="itemToAwait"></param>
/// <returns></returns>
public async Task <TCacheItem> AwaitCacheItem(LazyAwaitableCacheItem <TCacheItem> itemToAwait)
{
return(await itemToAwait.GetTask().ConfigureAwait(false));
}
