latest entity caching primitives

1 files changed, 74 insertions, 0 deletions

diff --git a/lib/VNLib.Plugins.Extensions.VNCache/src/DataModel/TransparentEntityCache.cs b/lib/VNLib.Plugins.Extensions.VNCache/src/DataModel/TransparentEntityCache.cs
new file mode 100644
index 0000000..90aeb74
--- /dev/null
+++ b/lib/VNLib.Plugins.Extensions.VNCache/src/DataModel/TransparentEntityCache.cs
@@ -0,0 +1,74 @@
+/*
+* Copyright (c) 2024 Vaughn Nugent
+* 
+* Library: VNLib
+* Package: VNLib.Plugins.Extensions.VNCache
+* File: EntityCacheExtensions.cs 
+*
+* EntityCacheExtensions.cs is part of VNLib.Plugins.Extensions.VNCache 
+* which is part of the larger VNLib collection of libraries and utilities.
+*
+* VNLib.Plugins.Extensions.VNCache is free software: you can redistribute it and/or modify 
+* it under the terms of the GNU Affero General Public License as 
+* published by the Free Software Foundation, either version 3 of the
+* License, or (at your option) any later version.
+*
+* VNLib.Plugins.Extensions.VNCache is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU Affero General Public License for more details.
+*
+* You should have received a copy of the GNU Affero General Public License
+* along with this program.  If not, see https://www.gnu.org/licenses/.
+*/
+
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace VNLib.Plugins.Extensions.VNCache.DataModel
+{
+    /// <summary>
+    /// A cache proxy that sits transparently between a backing store and the caller
+    /// to cache unique entities
+    /// </summary>
+    /// <typeparam name="TEntity"></typeparam>
+    /// <param name="store">The backing entity data store</param>
+    /// <param name="cache">The entity cache used to fetch</param>
+    public class TransparentEntityCache<TEntity>(IEntityStore<TEntity> store, EntityResultCache<TEntity> cache) : IEntityStore<TEntity> 
+        where TEntity : class
+    {
+
+        ///<inheritdoc/>
+        public Task<TEntity?> GetAsync<TRequest>(TRequest request, CancellationToken cancellation = default) 
+            where TRequest : IEntityCacheKey
+        {
+            return cache.FetchAsync(request, store.GetAsync, cancellation);
+        }
+
+        ///<inheritdoc/>
+        public Task<bool> RemoveAsync<TRequest>(TRequest request, CancellationToken cancellation = default)
+            where TRequest : IEntityCacheKey
+        {
+            Task<bool> _fromCache = cache.RemoveAsync(request, cancellation)
+                .ContinueWith(static (_) => true, TaskScheduler.Default);
+
+            Task<bool> _fromStore = store.RemoveAsync(request, cancellation);
+
+            return Task.WhenAll(_fromCache, _fromStore)
+                .ContinueWith(static (t) => t.Result.All(static r => r), TaskScheduler.Default);
+        }
+
+        ///<inheritdoc/>
+        public Task UpsertAsync<TRequest>(TRequest request, TEntity entity, CancellationToken cancellation = default)
+            where TRequest : IEntityCacheKey
+        {
+            //Remove key from cache but push update to store
+            Task _fromCache = cache.RemoveAsync(request, cancellation);
+
+            Task _fromStore = store.UpsertAsync(request, entity, cancellation);
+
+            return Task.WhenAll(_fromCache, _fromStore);
+        }
+    }
+}