Implementing AuthDataCache

DotBased.ASP.Auth/AuthDataCache.cs

@@ -0,0 +1,91 @@
+using System.Collections.ObjectModel;
+using DotBased.ASP.Auth.Domains.Auth;
+
+namespace DotBased.ASP.Auth;
+
+public class AuthDataCache
+{
+    public AuthDataCache(IAuthDataRepository dataRepository, BasedAuthConfiguration configuration)
+    {
+        DataRepository = dataRepository;
+        _configuration = configuration;
+    }
+
+    public readonly IAuthDataRepository DataRepository;
+    private readonly BasedAuthConfiguration _configuration;
+
+    private readonly CacheNodeCollection<AuthenticationStateModel> _authenticationStateCollection = [];
+
+    public Result PurgeSessionFromCache(string id) => _authenticationStateCollection.Remove(id) ? Result.Ok() : Result.Failed("Failed to purge session state from cache!");
+
+    public async Task<Result<AuthenticationStateModel>> RequestAuthStateAsync(string id)
+    {
+        if (_authenticationStateCollection.TryGetValue(id, out var node))
+        {
+            if (node.Object == null)
+            {
+                _authenticationStateCollection.Remove(id);
+                return Result<AuthenticationStateModel>.Failed($"Returned object is null, removing entry [{id}] from cache!");
+            }
+
+            if (node.IsValidLifespan(_configuration.CachedAuthSessionLifespan))
+                return Result<AuthenticationStateModel>.Ok(node.Object);
+        }
+        
+        var dbResult = await DataRepository.GetAuthenticationStateAsync(id);
+        if (!dbResult.Success || dbResult.Value == null)
+        {
+            _authenticationStateCollection.Remove(id);
+            return Result<AuthenticationStateModel>.Failed("Unknown session state!");
+        }
+
+        if (node == null)
+            node = new CacheNode<AuthenticationStateModel>(dbResult.Value);
+        else
+            node.UpdateObject(dbResult.Value);
+        if (node.Object != null)
+            return Result<AuthenticationStateModel>.Ok(node.Object);
+        return node.Object != null ? Result<AuthenticationStateModel>.Ok(node.Object) : Result<AuthenticationStateModel>.Failed("Failed to get db object!");
+    }
+
+    /*
+     *
+     */
+}
+
+public class CacheNode<T> where T : class
+{
+    public CacheNode(T obj)
+    {
+        Object = obj;
+    }
+    public T? Object { get; private set; }
+    public DateTime DateCached { get; private set; } = DateTime.Now;
+
+    public void UpdateObject(T obj)
+    {
+        Object = obj;
+        DateCached = DateTime.Now;
+    }
+
+    /// <summary>
+    /// Checks if the cached object is within the given lifespan.
+    /// </summary>
+    /// <param name="lifespan">The max. lifespan</param>
+    public bool IsValidLifespan(TimeSpan lifespan) => DateCached.Add(lifespan) < DateTime.Now;
+
+    public override bool Equals(object? obj)
+    {
+        if (obj is CacheNode<T> cacheObj)
+            return typeof(T).Equals(cacheObj.Object);
+        return false;
+    }
+
+    public override int GetHashCode() => typeof(T).GetHashCode();
+    public override string ToString() => typeof(T).ToString();
+}
+
+public class CacheNodeCollection<TItem> : KeyedCollection<string, CacheNode<TItem>> where TItem : class
+{
+    protected override string GetKeyForItem(CacheNode<TItem> item) => item.Object?.ToString() ?? string.Empty;
+}