From 86a7dfbac3d982f29cd9dc1dc5eaae3543991a08 Mon Sep 17 00:00:00 2001
From: Rockford Lhotka <rocky@lhotka.net>
Date: Tue, 30 Jan 2024 21:28:57 -0800
Subject: [PATCH] #3657 Support .NET 7 context behavior

---
 .../ApplicationContextManagerInMemory.cs      | 220 ++++++++++++++++++
 Source/Csla.Blazor/ConfigurationExtensions.cs |  15 +-
 2 files changed, 233 insertions(+), 2 deletions(-)
 create mode 100644 Source/Csla.AspNetCore/Blazor/ApplicationContextManagerInMemory.cs

diff --git a/Source/Csla.AspNetCore/Blazor/ApplicationContextManagerInMemory.cs b/Source/Csla.AspNetCore/Blazor/ApplicationContextManagerInMemory.cs
new file mode 100644
index 0000000000..a7643bbda5
--- /dev/null
+++ b/Source/Csla.AspNetCore/Blazor/ApplicationContextManagerInMemory.cs
@@ -0,0 +1,220 @@
+#if NET5_0_OR_GREATER
+//-----------------------------------------------------------------------
+// <copyright file="ApplicationContextManagerInMemory.cs" company="Marimer LLC">
+//     Copyright (c) Marimer LLC. All rights reserved.
+//     Website: https://cslanet.com
+// </copyright>
+// <summary>Application context manager that uses HttpContextAccessor</summary>
+//-----------------------------------------------------------------------
+using Csla.Core;
+using Microsoft.AspNetCore.Components.Authorization;
+using System;
+using System.Security.Claims;
+using System.Security.Principal;
+using System.Threading.Tasks;
+
+namespace Csla.AspNetCore.Blazor
+{
+  /// <summary>
+  /// Application context manager that uses HttpContextAccessor when 
+  /// resolving HttpContext to store context values.
+  /// </summary>
+  public class ApplicationContextManagerInMemory : IContextManager, IDisposable
+  {
+    private ContextDictionary LocalContext { get; set; }
+    private ContextDictionary ClientContext { get; set; }
+    private IPrincipal CurrentPrincipal { get; set; }
+    private readonly ClaimsPrincipal UnauthenticatedPrincipal = new();
+    private bool disposedValue;
+
+    /// <summary>
+    /// Gets the current HttpContext instance.
+    /// </summary>
+    protected AuthenticationStateProvider AuthenticationStateProvider { get; private set; }
+
+    /// <summary>
+    /// Gets or sets a reference to the current ApplicationContext.
+    /// </summary>
+    public ApplicationContext ApplicationContext { get; set; }
+
+    /// <summary>
+    /// Gets the active circuit state.
+    /// </summary>
+    protected ActiveCircuitState ActiveCircuitState { get; private set; }
+
+    /// <summary>
+    /// Creates an instance of the object, initializing it
+    /// with the required IServiceProvider.
+    /// </summary>
+    /// <param name="authenticationStateProvider">AuthenticationStateProvider service</param>
+    /// <param name="activeCircuitState"></param>
+    public ApplicationContextManagerInMemory(AuthenticationStateProvider authenticationStateProvider, ActiveCircuitState activeCircuitState)
+    {
+      AuthenticationStateProvider = authenticationStateProvider;
+      ActiveCircuitState = activeCircuitState;
+      CurrentPrincipal = UnauthenticatedPrincipal;
+      AuthenticationStateProvider.AuthenticationStateChanged += AuthenticationStateProvider_AuthenticationStateChanged;
+      InitializeUser();
+    }
+
+    private void InitializeUser()
+    {
+      Task<AuthenticationState> task = default;
+      try
+      {
+        task = AuthenticationStateProvider.GetAuthenticationStateAsync();
+      }
+      catch (InvalidOperationException ex)
+      {
+        task = Task.FromResult(new AuthenticationState((ClaimsPrincipal)UnauthenticatedPrincipal));
+        string message = ex.Message;
+        if (message.Contains(nameof(AuthenticationStateProvider.GetAuthenticationStateAsync))
+            && message.Contains(nameof(IHostEnvironmentAuthenticationStateProvider.SetAuthenticationState)))
+        {
+          SetHostPrincipal(task);
+        }
+        else
+        {
+          throw;
+        }
+      }
+      AuthenticationStateProvider_AuthenticationStateChanged(task);
+    }
+
+    private void AuthenticationStateProvider_AuthenticationStateChanged(Task<AuthenticationState> task)
+    {
+      if (task is null)
+      {
+        CurrentPrincipal = UnauthenticatedPrincipal;
+      }
+      else
+      {
+        task.ContinueWith((t) =>
+        {
+          if (task.IsCompletedSuccessfully && task.Result != null)
+            CurrentPrincipal = task.Result.User;
+          else
+            CurrentPrincipal = UnauthenticatedPrincipal;
+        });
+      }
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether this
+    /// context manager is valid for use in
+    /// the current environment.
+    /// </summary>
+    public bool IsValid
+    {
+      get { return ActiveCircuitState.CircuitExists; }
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether the context manager
+    /// is stateful.
+    /// </summary>
+    public bool IsStatefulContext => true;
+
+    /// <summary>
+    /// Gets the current principal.
+    /// </summary>
+    public IPrincipal GetUser()
+    {
+      return CurrentPrincipal;
+    }
+
+    /// <summary>
+    /// Attempts to set the current principal on the registered
+    /// IHostEnvironmentAuthenticationStateProvider service.
+    /// </summary>
+    /// <param name="principal">Principal object.</param>
+    public virtual void SetUser(IPrincipal principal)
+    {
+      if (!ReferenceEquals(CurrentPrincipal, principal))
+      {
+        if (principal is ClaimsPrincipal claimsPrincipal)
+        {
+          CurrentPrincipal = principal;
+          SetHostPrincipal(Task.FromResult(new AuthenticationState(claimsPrincipal)));
+        }
+        else
+        {
+          throw new ArgumentException("typeof(principal) != ClaimsPrincipal");
+        }
+      }
+    }
+
+    private void SetHostPrincipal(Task<AuthenticationState> task)
+    {
+      if (AuthenticationStateProvider is IHostEnvironmentAuthenticationStateProvider hostProvider)
+        hostProvider.SetAuthenticationState(task);
+    }
+
+    /// <summary>
+    /// Gets the local context.
+    /// </summary>
+    public ContextDictionary GetLocalContext()
+    {
+      if (LocalContext == null)
+        LocalContext = new ContextDictionary();
+      return LocalContext;
+    }
+
+    /// <summary>
+    /// Sets the local context.
+    /// </summary>
+    /// <param name="localContext">Local context.</param>
+    public void SetLocalContext(ContextDictionary localContext)
+    {
+      LocalContext = localContext;
+    }
+
+    /// <summary>
+    /// Gets the client context.
+    /// </summary>
+    /// <param name="executionLocation"></param>
+    public ContextDictionary GetClientContext(ApplicationContext.ExecutionLocations executionLocation)
+    {
+      if (ClientContext == null)
+        ClientContext = new ContextDictionary();
+      return ClientContext;
+    }
+
+    /// <summary>
+    /// Sets the client context.
+    /// </summary>
+    /// <param name="clientContext">Client context.</param>
+    /// <param name="executionLocation"></param>
+    public void SetClientContext(ContextDictionary clientContext, ApplicationContext.ExecutionLocations executionLocation)
+    {
+      ClientContext = clientContext;
+    }
+
+    /// <summary>
+    /// Dispose this object's resources.
+    /// </summary>
+    /// <param name="disposing"></param>
+    protected virtual void Dispose(bool disposing)
+    {
+      if (!disposedValue)
+      {
+        if (disposing)
+        {
+          AuthenticationStateProvider.AuthenticationStateChanged -= AuthenticationStateProvider_AuthenticationStateChanged;
+        }
+        disposedValue = true;
+      }
+    }
+
+    /// <summary>
+    /// Dispose this object's resources.
+    /// </summary>
+    public void Dispose()
+    {
+      // Do not change this code. Put cleanup code in 'Dispose(bool disposing)' method
+      Dispose(disposing: true);
+      GC.SuppressFinalize(this);
+    }
+  }
+}
+#endif
\ No newline at end of file
diff --git a/Source/Csla.Blazor/ConfigurationExtensions.cs b/Source/Csla.Blazor/ConfigurationExtensions.cs
index 95dd03b6a8..80fcd7d5b4 100644
--- a/Source/Csla.Blazor/ConfigurationExtensions.cs
+++ b/Source/Csla.Blazor/ConfigurationExtensions.cs
@@ -45,9 +45,14 @@ public static CslaOptions AddServerSideBlazor(this CslaOptions config, Action<Bl
       // minimize PropertyChanged events
       config.BindingOptions.PropertyChangedMode = ApplicationContext.PropertyChangedModes.Windows;
 
-      var managerType = Type.GetType("Csla.AspNetCore.Blazor.ApplicationContextManagerBlazor,Csla.AspNetCore");
+      string managerTypeName;
+      if (blazorOptions.UseInMemoryApplicationContextManager)
+        managerTypeName = "Csla.AspNetCore.Blazor.ApplicationContextManagerInMemory,Csla.AspNetCore";
+      else
+        managerTypeName = "Csla.AspNetCore.Blazor.ApplicationContextManagerBlazor,Csla.AspNetCore";
+      var managerType = Type.GetType(managerTypeName);
       if (managerType is null)
-        throw new TypeLoadException("Csla.AspNetCore.Blazor.ApplicationContextManagerBlazor,Csla.AspNetCore");
+        throw new TypeLoadException(managerTypeName);
       var contextManagerType = typeof(Core.IContextManager);
       var managers = config.Services.Where(i => i.ServiceType.Equals(contextManagerType)).ToList();
       foreach ( var manager in managers )
@@ -82,6 +87,12 @@ public class BlazorServerConfigurationOptions
     /// </summary>
     public bool UseCslaPermissionsPolicy { get; set; } = true;
 
+    /// <summary>
+    /// Gets or sets a value indicating whether to use the
+    /// pre-Blazor 8 in-memory context manager.
+    /// </summary>
+    public bool UseInMemoryApplicationContextManager { get; set; }
+
     /// <summary>
     /// Gets or sets the type of the ISessionManager service.
     /// </summary>