public IMethodReturn Invoke(IMethodInvocation input, GetNextHandlerDelegate getNext)
{
var cacheKey = _keyGenerator.GenerateKey(input);
var methodIsTask = input.MethodBase.IsGenericTask();
var returnType = input.MethodBase.GetReturnType();
var cachedResult = typeof(ICache).GetMethod("Get")
.MakeGenericMethod(returnType)
.Invoke(_cache, new object[] { cacheKey });
object unwrappedResult = null;
var scheduleDurableRefresh = false;
//Force cache miss for durable results that are behind
if (cachedResult != null && AbsoluteExpiration != null)
{
var lastUpdate = (DateTime)CacheExtensions.GetLastUpdate((dynamic)cachedResult);
var expires = (DateTime)CacheExtensions.GetExpires((dynamic)cachedResult);
if (DateTime.UtcNow.Subtract(lastUpdate).TotalSeconds > MaximumStaleness.TotalSeconds)
{
if (RescheduleStale && DateTime.UtcNow.Add(Expiration) < expires)
{
scheduleDurableRefresh = true;
}
else
{
cachedResult = null;
}
}
}
// Nothing is cached for this method
if (cachedResult == null)
{
// Get a new result
var newResult = getNext()(input, getNext);
//Do not cache exceptions
if (newResult.Exception == null)
{
if (methodIsTask)
{
newResult.ReturnValue = (dynamic)typeof(CacheExtensions).GetMethod("AddToCacheAsync")
.MakeGenericMethod(returnType)
.Invoke(null, new object[] { _cache, newResult.ReturnValue,
cacheKey, DateTime.UtcNow.Add(AbsoluteExpiration ?? Expiration) });
}
else
{
typeof(CacheExtensions).GetMethod("AddToCache")
.MakeGenericMethod(returnType)
.Invoke(null, new object[] { _cache, newResult.ReturnValue,
cacheKey, DateTime.UtcNow.Add(AbsoluteExpiration ?? Expiration) });
}
//queue refresh if configured by the user
scheduleDurableRefresh = AbsoluteExpiration != null;
}
unwrappedResult = newResult.ReturnValue;
}
else
{
if (methodIsTask)
{
var unwrappedResultMissingTask = CacheExtensions.Unwrap((dynamic)cachedResult);
unwrappedResult = typeof(Task).GetMethod("FromResult")
.MakeGenericMethod(input.MethodBase.GetGenericReturnTypeArguments())
.Invoke(null, new object[] { unwrappedResultMissingTask });
}
else
{
unwrappedResult = CacheExtensions.Unwrap((dynamic)cachedResult);
}
}
if (scheduleDurableRefresh)
{
var parameters = new object[input.Inputs.Count];
input.Inputs.CopyTo(parameters, 0);
var queue = _container.Resolve <IDurableCacheQueue>();
queue.ScheduleRefresh(new DurableCacheRefreshEvent
{
AbsoluteExpiration = AbsoluteExpiration.Value,
CacheName = _cacheName,
Key = cacheKey,
Method = new DurableMethod
{
DeclaringType = input.Target.GetType(),
Interface = input.MethodBase.DeclaringType,
Name = input.MethodBase.Name,
Parameters = input.MethodBase.GetParameters()
.Select(p => p.ParameterType).ToArray()
},
Parameters = parameters,
RefreshTime = Expiration,
UtcLifetime = cachedResult != null ? (DateTime)CacheExtensions.GetExpires((dynamic)cachedResult) :
DateTime.UtcNow.Add(AbsoluteExpiration.Value),
});
}
var arguments = new object[input.Inputs.Count];
input.Inputs.CopyTo(arguments, 0);
return(new VirtualMethodReturn(input, unwrappedResult, arguments));
}