private static bool IsSimpleCaching(CacheExpires expires, ICacheSignal signal)
{
// signal provided - complex caching
if (signal != null)
{
return(false);
}
// no signal, no expires - simple caching
if (expires == null)
{
return(true);
}
// expires absolute has meaningful value - complex caching
if (expires.Absolute != CacheExpires.NoAbsoluteExpiration &&
expires.Absolute != DateTime.MaxValue)
{
return(false);
}
// expires sliding has meaningful value - complex caching
if (expires.Sliding != CacheExpires.NoSlidingExpiration &&
expires.Sliding != TimeSpan.MaxValue &&
expires.Sliding != TimeSpan.Zero)
{
return(false);
}
// no signal, no meaningful expires value - simple caching
return(true);
}
public void Store(string identifier, CacheExpires expires, ICacheSignal signal, object item)
{
_cache.Insert(
identifier,
item,
SignalDependency.For(signal),
(expires ?? CacheExpires.Empty).Absolute,
(expires ?? CacheExpires.Empty).Sliding);
}
public void Store(string identifier, CacheExpires expires, ICacheSignal signal, object item)
{
_cache[identifier] = new Entry {Value = item, UtcExpires = ToAbsolute(expires)};
if (signal != null)
{
signal.Changed += (sender, e) => _cache.Remove(identifier);
}
}
public void Store(string identifier, CacheExpires expires, ICacheSignal signal, object item)
{
_cache[identifier] = new Entry {
Value = item, UtcExpires = ToAbsolute(expires)
};
if (signal != null)
{
signal.Changed += (sender, e) => _cache.Remove(identifier);
}
}
public void Store(string identifier, CacheExpires expires, ICacheSignal signal, object item)
{
if (IsSimpleCaching(expires, signal))
{
// use MR cache service for simple identifier-only caching
_monorailCacheProvider.Store(identifier, item);
}
else
{
// use the httpcontext cache when storing with expires or signal args in effect
_fallbackCacheService.Store(identifier, expires, signal, item);
}
}
private DateTime ToAbsolute(CacheExpires expires)
{
// this is less sophisticated than the web caching implementation, but
// it only needs to satisfy expectations of unit tests. they should always
// use utc for abs
if (expires == null)
return CacheExpires.NoAbsoluteExpiration;
if (expires.Sliding != CacheExpires.NoSlidingExpiration)
{
return UtcNow.Add(expires.Sliding);
}
return expires.Absolute;
}
private DateTime ToAbsolute(CacheExpires expires)
{
// this is less sophisticated than the web caching implementation, but
// it only needs to satisfy expectations of unit tests. they should always
// use utc for abs
if (expires == null)
{
return(CacheExpires.NoAbsoluteExpiration);
}
if (expires.Sliding != CacheExpires.NoSlidingExpiration)
{
return(UtcNow.Add(expires.Sliding));
}
return(expires.Absolute);
}
public void Store(string identifier, CacheExpires expires, ICacheSignal signal, object item)
{
}
public void Store(string identifier, CacheExpires expires, ICacheSignal signal, object item)
{
}
