public async Task <CachedObject <TResult> > GetAsync <TResult>(ProxiedMethodInvocation <T, TResult> proxiedMethodInvocation, CachePolicy cachePolicy)
{
return(await Task.Factory.StartNew(() =>
{
var hash = proxiedMethodInvocation.GetHashString();
DictionaryCacheItem cachedObject;
if (_cache.TryGetValue(hash, out cachedObject))
{
if (cachedObject.ThrownException != null && cachedObject.Created.AddSeconds(cachePolicy.ExceptionCacheDuration) > DateTime.Now)
{
return new CachedObject <TResult>(CachedObjectState.Exception, cachedObject.ThrownException);
}
else if (cachedObject.ThrownException != null)
{
return new CachedObject <TResult>(CachedObjectState.None, null);
}
if (cachedObject.AbsoluteDuration.TotalSeconds > 0 && cachedObject.Created + cachedObject.AbsoluteDuration < DateTime.Now)
{
return new CachedObject <TResult>(CachedObjectState.None, null);
}
return new CachedObject <TResult>(cachedObject.IsExpired ? CachedObjectState.Stale : CachedObjectState.Fresh, (TResult)cachedObject.Object);
}
return CachedObject <TResult> .Empty();
}));
}
public async Task StoreExceptionAsync <TResult>(ProxiedMethodInvocation <T, TResult> proxiedMethodInvocation, CachePolicy cachePolicy, Exception e)
{
await Task.Factory.StartNew(() =>
{
var hash = proxiedMethodInvocation.GetHashString();
var duration = TimeSpan.FromSeconds(cachePolicy.CacheDuration);
var absoluteDuration = TimeSpan.FromSeconds(cachePolicy.MaxAge);
_cache[hash] = new DictionaryCacheItem(e, duration, absoluteDuration);
});
}
public async Task <CachedObject <TResult> > GetAsync <TResult>(ProxiedMethodInvocation <T, TResult> proxiedMethodInvocation, CachePolicy cachePolicy)
{
var key = proxiedMethodInvocation.GetHashString(_hashScramble);
var memcachedItem = await _memcachedCluster.Get(key);
if (memcachedItem != null)
{
MemcachedObject <TResult> cacheItem;
using (var zipStream = new GZipStream(memcachedItem.Data, CompressionMode.Decompress))
{
using (var streamReader = new StreamReader(zipStream))
{
var textReader = new JsonTextReader(streamReader);
try
{
cacheItem = _serializer.Deserialize <MemcachedObject <TResult> >(textReader);
}
catch (JsonSerializationException)
{
//This exception occurs if whatever is in memcached is impossible to deserialize. It's a tricky case, but we'll have to report back that nothing is in there.
return(new CachedObject <TResult>(CachedObjectState.None, default(TResult)));
}
}
}
if (cacheItem == null)
{
return(new CachedObject <TResult>(CachedObjectState.None, default(TResult)));
}
if (cacheItem.IsException && cacheItem.Created.AddSeconds(cachePolicy.ExceptionCacheDuration) > DateTime.Now)
{
return(new CachedObject <TResult>(CachedObjectState.Exception, cacheItem.Exception));
}
else if (cacheItem.IsException)
{
return(new CachedObject <TResult>(CachedObjectState.None, default(TResult)));
}
var fresh = cacheItem.Created.AddSeconds(cachePolicy.CacheDuration) > DateTime.Now;
var state = fresh ? CachedObjectState.Fresh : CachedObjectState.Stale;
if (cachePolicy.DiscardStale && state == CachedObjectState.Stale)
{
return(new CachedObject <TResult>(CachedObjectState.None, default(TResult)));
}
return(new CachedObject <TResult>(state, cacheItem.Object));
}
return(new CachedObject <TResult>(CachedObjectState.None, default(TResult)));
}
public async Task StoreAsync <TResult>(ProxiedMethodInvocation <T, TResult> proxiedMethodInvocation, CachePolicy cachePolicy, TResult data)
{
var key = proxiedMethodInvocation.GetHashString(_hashScramble);
var cachedObject = new MemcachedObject <TResult>()
{
Created = DateTime.Now,
Object = data
};
var bytes = SerializeAndZip(cachedObject);
if (cachePolicy.MaxAge > 0)
{
await _memcachedCluster.Set(key, bytes, new MemcachedStorageOptions()
{
ExpirationTime = TimeSpan.FromSeconds(cachePolicy.MaxAge)
});
}
else
{
await _memcachedCluster.Set(key, bytes);
}
}
