/// <summary>A DelayedQuery<TResult> extension method that future value.</summary>
/// <typeparam name="TResult">Type of the result.</typeparam>
/// <param name="query">The query to act on.</param>
/// <returns>A FutureQueryValue<TResult,TResult></returns>
public static QueryFutureValue <TResult> FutureValue <TResult>(this QueryDelayed <TResult> query)
{
var objectQuery = query.Source.GetObjectQuery();
var futureBatch = QueryFutureManager.AddOrGetBatch(objectQuery.Context);
var futureQuery = new QueryFutureValue <TResult>(futureBatch, objectQuery);
futureBatch.Queries.Add(futureQuery);
return(futureQuery);
}
/// <summary>
/// Return the result of the <paramref name="query" /> from the cache. If the query is not cached
/// yet, the query is materialized and cached before being returned.
/// </summary>
/// <typeparam name="T">Generic type parameter.</typeparam>
/// <param name="query">The query to cache in the QueryCacheManager.</param>
/// <param name="absoluteExpiration">The fixed date and time at which the cache entry will expire.</param>
/// <param name="tags">
/// A variable-length parameters list containing tag to use for the cache
/// key and expiration.
/// </param>
/// <returns>The result of the query.</returns>
public static T FromCache <T>(this QueryDelayed <T> query, DateTimeOffset absoluteExpiration, params string[] tags)
{
var key = QueryCacheManager.GetCacheKey(query, tags);
var item = QueryCacheManager.Cache.Get(key);
if (item == null)
{
item = query.Execute();
QueryCacheManager.Cache.AddOrGetExisting(key, item, absoluteExpiration);
QueryCacheManager.AddCacheTag(key, tags);
}
return((T)item);
}
/// <summary>
/// Return the result of the <paramref name="query" /> from the cache. If the query is not cached
/// yet, the query is materialized and cached before being returned.
/// </summary>
/// <typeparam name="T">The generic type of the query.</typeparam>
/// <param name="query">The query to cache in the QueryCacheManager.</param>
/// <param name="policy">The policy to use to cache the query.</param>
/// <param name="tags">
/// A variable-length parameters list containing tag to use for the cache
/// key and expiration.
/// </param>
/// <returns>The result of the query.</returns>
public static T FromCache <T>(this QueryDelayed <T> query, CacheItemPolicy policy, params string[] tags)
{
var key = QueryCacheManager.GetCacheKey(query, tags);
var item = QueryCacheManager.Cache.Get(key);
if (item == null)
{
item = query.Execute();
QueryCacheManager.Cache.AddOrGetExisting(key, item, policy);
QueryCacheManager.AddCacheTag(key, tags);
}
return((T)item);
}
/// <summary>
/// Return the result of the <paramref name="query" /> from the cache. If the query is not cached
/// yet, the query is materialized asynchronously and cached before being returned.
/// </summary>
/// <typeparam name="T">Generic type parameter.</typeparam>
/// <param name="query">The query to cache in the QueryCacheManager.</param>
/// <param name="tags">
/// A variable-length parameters list containing tag to use for the cache
/// key and expiration.
/// </param>
/// <returns>The result of the query.</returns>
public static async Task <T> FromCacheAsync <T>(this QueryDelayed <T> query, params string[] tags)
{
return(await query.FromCacheAsync(QueryCacheManager.DefaultCacheItemPolicy, tags));
}
/// <summary>
/// Return the result of the <paramref name="query" /> from the cache. If the query is not cached
/// yet, the query is materialized and cached before being returned.
/// </summary>
/// <typeparam name="T">Generic type parameter.</typeparam>
/// <param name="query">The query to cache in the QueryCacheManager.</param>
/// <param name="tags">
/// A variable-length parameters list containing tag to use for the cache
/// key and expiration.
/// </param>
/// <returns>The result of the query.</returns>
public static T FromCache <T>(this QueryDelayed <T> query, params string[] tags)
{
return(query.FromCache(QueryCacheManager.DefaultCacheItemPolicy, tags));
}
/// <summary>Gets cache key used to cache or retrieve query from the QueryCacheManager.</summary>
/// <typeparam name="T">Generic type parameter.</typeparam>
/// <param name="query">The query to cache or retrieve from the QueryCacheManager.</param>
/// <param name="tags">A variable-length parameters list containing tag to create the cache key.</param>
/// <returns>The cache key used to cache or retrieve query from the QueryCacheManager.</returns>
public static string GetCacheKey <T>(QueryDelayed <T> query, string[] tags)
{
return(CachePrefix + string.Join(";", tags) + query.Source);
}