public static T GetKeyT <TId>(TId id, int decaysec, Func <TId, T> factory)
{
// Get object from cache and Load/Create it if needed.
// NOTE: await Task<T> cant be done inside lock !???
// TId = int or string.
// like IMemoryCache GetOrCreate
string cacheKey = string.Concat(typeof(T).Name, CacheData.kSep, id);
lock (_WeakRefs)
{
// Find in the hard ref cache first.
T obj = (T)CacheData.Get(cacheKey);
if (obj != null)
{
return(obj); // got it.
}
// Fallback to the weak ref cache next. e.g. someone has a ref that existed longer than the cache? get it.
WeakReference wr;
if (_WeakRefs.TryGetValue(cacheKey, out wr))
{
if (wr.IsAlive)
{
// someone still has a ref to this . so continue to use it. we should reload this from the db though.
obj = (T)wr.Target;
}
}
// lastly load it if we cant find it otherwise.
if (factory != null)
{
// NOTE: await Task<T> cant be done inside lock !
T objLoad = factory.Invoke(id);
ValidState.ThrowIfNull(objLoad, nameof(objLoad));
if (obj == null)
{
obj = objLoad; // Fresh load.
if (wr != null)
{
_WeakRefs.Remove(cacheKey);
}
_WeakRefs.Add(cacheKey, new WeakReference(obj));
}
else
{
PropertyUtil.InjectProperties <T>(obj, objLoad); // refresh props in old weak ref.
}
}
if (obj != null)
{
// store it in cache. refresh decaySec.
CacheData.Set(cacheKey, obj, decaysec);
}
return(obj);
}
}
public static T Get(string id)
{
// Find the object in the cache if possible.
if (id == null) // shortcut.
{
return(null);
}
ValidState.ThrowIfWhiteSpace(id, nameof(id)); // must have id. else use GetSingleton
string cacheKey = MakeKey(id);
object o = CacheData.Get(cacheKey);
return((T)o);
}
public static T GetSingleton()
{
// Get singleton. Instance()
return((T)CacheData.Get(typeof(T).Name));
}
