/// <summary>
/// Helper method to more easily create an Absolute Expiration CacheItemPolicy directly from a Configuration
/// Parameter name that has the TTL Seconds; with Default fallback if it does not exist.
/// </summary>
/// <param name="ttlSecondsConfigKey"></param>
/// <param name="callbackWhenCacheEntryRemoved"></param>
/// <returns></returns>
public static CacheItemPolicy NewAbsoluteExpirationPolicy(string ttlSecondsConfigKey, Action <CacheEntryRemovedArguments> callbackWhenCacheEntryRemoved = null)
{
var timeSpanToLive = LazyCacheConfig.GetCacheTTLFromConfig(ttlSecondsConfigKey, LazyCacheConfig.NeverCacheTTL);
if (timeSpanToLive.TotalMilliseconds > 0)
{
return(LazyCachePolicy.NewAbsoluteExpirationPolicy(timeSpanToLive, callbackWhenCacheEntryRemoved));
}
return(null);
}
/// <summary>
/// Helper method to more easily create an Absolute Expiration CacheItemPolicy directly from a Configuration
/// Parameter names that has the TTL Seconds; this will return the first identified valid configuration key.
/// </summary>
/// <param name="ttlConfigKeysToSearch"></param>
/// <param name="callbackWhenCacheEntryRemoved"></param>
/// <returns></returns>
public static CacheItemPolicy NewAbsoluteExpirationPolicy(string[] ttlConfigKeysToSearch, Action <CacheEntryRemovedArguments> callbackWhenCacheEntryRemoved = null)
{
var timeSpanToLive = LazyCacheConfig.GetCacheTTLFromConfig(ttlConfigKeysToSearch, LazyCacheConfig.NeverCacheTTL);
if (timeSpanToLive.TotalMilliseconds > 0)
{
return(LazyCachePolicy.NewAbsoluteExpirationPolicy(timeSpanToLive, callbackWhenCacheEntryRemoved));
}
//Finally return the cache policy for the first identified valid configuration key.
return(null);
}
/// <summary>
/// Initialize the Cache TTL Seconds from Configuration in a fully ThreadSafe way by finding the configuration value
/// of the first valid config key specified; searching in the order defined int the array.
/// </summary>
/// <param name="configKeysToSearch"></param>
/// <param name="defaultMinimumTTL"></param>
/// <returns></returns>
public static TimeSpan GetCacheTTLFromConfig(string[] configKeysToSearch, TimeSpan defaultMinimumTTL)
{
foreach (var configKey in configKeysToSearch)
{
var timeSpanToLive = LazyCacheConfig.GetCacheTTLFromConfig(configKey, LazyCacheConfig.MissingCacheTTL);
if (timeSpanToLive == NeverCacheTTL || timeSpanToLive.TotalMilliseconds > 0)
{
return(timeSpanToLive);
}
}
return(defaultMinimumTTL);
}
