Updating the PR now that MSAL.NET's TokenCacheNotificationArgs has a member named IsApplicationTokenCache, brought by AzureAD/microsoft-authentication-library-for-dotnet#1448

cc: @bgavrilMS @jennyf19

Author: jmprieur

Microsoft.Identity.Web/Microsoft.Identity.Web.csproj

@@ -57,6 +57,6 @@
     <PackageReference Include="Microsoft.AspNetCore.Authentication.AzureAD.UI" Version="2.2.0" />
     <PackageReference Include="Microsoft.AspNetCore.Authentication.AzureADB2C.UI" Version="2.2.0" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="2.2.0" />
-    <PackageReference Include="Microsoft.Identity.Client" Version="4.3.1" />
+    <PackageReference Include="Microsoft.Identity.Client" Version="4.5.1-internal20191022.1isappcache" />
   </ItemGroup>
 </Project>

Microsoft.Identity.Web/TokenCacheProviders/Distributed/DistributedTokenCacheAdapterExtension.cs

@@ -29,7 +29,7 @@ public static IServiceCollection AddDistributedAppTokenCache(
             this IServiceCollection services)
         {
             services.AddDistributedMemoryCache();
-            services.AddSingleton<IMsalAppTokenCacheProvider, MsalAppDistributedTokenCacheProvider>();
+            services.AddSingleton<IMsalTokenCacheProvider, MsalDistributedTokenCacheAdapter>();
             return services;
         }
 
@@ -42,7 +42,7 @@ public static IServiceCollection AddDistributedUserTokenCache(
         {
             services.AddDistributedMemoryCache();
             services.AddHttpContextAccessor();
-            services.AddSingleton<IMsalUserTokenCacheProvider, MsalPerUserDistributedTokenCacheProvider>();
+            services.AddSingleton<IMsalTokenCacheProvider, MsalDistributedTokenCacheAdapter>();
             return services;
         }
     }

Microsoft.Identity.Web/TokenCacheProviders/Distributed/MsalAppDistributedTokenCacheProvider.cs

@@ -59,20 +59,16 @@ public Task InitializeAsync(ITokenCache tokenCache, bool isAppTokenCache)
         /// <summary>
         /// Cache key
         /// </summary>
-        private string CacheKey
+        private string GetCacheKey(bool isAppTokenCache)
         {
-            get
+            if (isAppTokenCache)
             {
-                if (_isAppTokenCache)
-                {
-                    return $"{_azureAdOptions.Value.ClientId}_AppTokenCache";
-                }
-                else
-                {
-                    return _httpContextAccessor.HttpContext.User.GetMsalAccountId();
-                }
+                return $"{_azureAdOptions.Value.ClientId}_AppTokenCache";
+            }
+            else
+            {
+                return _httpContextAccessor.HttpContext.User.GetMsalAccountId();
             }
-
         }
 
         /// <summary>
@@ -87,18 +83,21 @@ private async Task OnAfterAccessAsync(TokenCacheNotificationArgs args)
             // if the access operation resulted in a cache update
             if (args.HasStateChanged)
             {
-                if (!string.IsNullOrWhiteSpace(CacheKey))
+                string cacheKey = GetCacheKey(args.IsApplicationTokenCache);
+                if (!string.IsNullOrWhiteSpace(cacheKey))
                 {
-                    await WriteCacheBytesAsync(CacheKey, args.TokenCache.SerializeMsalV3()).ConfigureAwait(false);
+                    await WriteCacheBytesAsync(cacheKey, args.TokenCache.SerializeMsalV3()).ConfigureAwait(false);
                 }
             }
         }
 
         private async Task OnBeforeAccessAsync(TokenCacheNotificationArgs args)
         {
-            if (!string.IsNullOrEmpty(CacheKey))
+            string cacheKey = GetCacheKey(args.IsApplicationTokenCache);
+
+            if (!string.IsNullOrEmpty(cacheKey))
             {
-                byte[] tokenCacheBytes = await ReadCacheBytesAsync(CacheKey).ConfigureAwait(false);
+                byte[] tokenCacheBytes = await ReadCacheBytesAsync(cacheKey).ConfigureAwait(false);
                 args.TokenCache.DeserializeMsalV3(tokenCacheBytes, shouldClearExistingCache: true);
             }
         }
@@ -111,7 +110,8 @@ protected virtual Task OnBeforeWriteAsync(TokenCacheNotificationArgs args)
 
         public async Task ClearAsync()
         {
-            await RemoveKeyAsync(CacheKey).ConfigureAwait(false);
+            // This is here a user token cache
+            await RemoveKeyAsync(GetCacheKey(false)).ConfigureAwait(false);
         }
 
         protected abstract Task WriteCacheBytesAsync(string cacheKey, byte[] bytes);

Microsoft.Identity.Web/TokenCacheProviders/Distributed/MsalPerUserDistributedTokenCacheProvider.cs

@@ -75,7 +75,7 @@ public static IServiceCollection AddSessionTokenCaches(this IServiceCollection s
         public static IServiceCollection AddSessionAppTokenCache(this IServiceCollection services)
         {
             services.AddHttpContextAccessor();
-            services.AddScoped<IMsalAppTokenCacheProvider, MsalAppSessionTokenCacheProvider>();
+            services.AddScoped<IMsalTokenCacheProvider, MsalSessionTokenCacheProvider>();
             return services;
         }
 
@@ -101,7 +101,7 @@ public static IServiceCollection AddSessionPerUserTokenCache(this IServiceCollec
             services.AddSession(option =>
             { option.Cookie.IsEssential = true; }
             );
-            services.AddScoped<IMsalUserTokenCacheProvider, MsalPerUserSessionTokenCacheProvider>();
+            services.AddScoped<IMsalTokenCacheProvider, MsalSessionTokenCacheProvider>();
             return services;
         }
     }