Add identity first iteration

Hcs.WebApp/Identity/IdentityRevalidatingAuthenticationStateProvider.cs

@@ -0,0 +1,45 @@
+using Hcs.WebApp.Data;
+using Microsoft.AspNetCore.Components.Authorization;
+using Microsoft.AspNetCore.Components.Server;
+using Microsoft.AspNetCore.Identity;
+using Microsoft.Extensions.Options;
+using System.Security.Claims;
+
+namespace Hcs.WebApp.Identity
+{
+    internal sealed class IdentityRevalidatingAuthenticationStateProvider(
+        ILoggerFactory loggerFactory,
+        IServiceScopeFactory scopeFactory,
+        IOptions<IdentityOptions> options) : RevalidatingServerAuthenticationStateProvider(loggerFactory)
+    {
+        protected override TimeSpan RevalidationInterval => TimeSpan.FromMinutes(30);
+
+        protected override async Task<bool> ValidateAuthenticationStateAsync(
+            AuthenticationState authenticationState, CancellationToken cancellationToken)
+        {
+            await using var scope = scopeFactory.CreateAsyncScope();
+
+            var userManager = scope.ServiceProvider.GetRequiredService<UserManager<AppUser>>();
+            return await ValidateSecurityStampAsync(userManager, authenticationState.User);
+        }
+
+        private async Task<bool> ValidateSecurityStampAsync(UserManager<AppUser> userManager, ClaimsPrincipal principal)
+        {
+            var user = await userManager.GetUserAsync(principal);
+            if (user is null)
+            {
+                return false;
+            }
+            else if (!userManager.SupportsUserSecurityStamp)
+            {
+                return true;
+            }
+            else
+            {
+                var principalStamp = principal.FindFirstValue(options.Value.ClaimsIdentity.SecurityStampClaimType);
+                var userStamp = await userManager.GetSecurityStampAsync(user);
+                return principalStamp == userStamp;
+            }
+        }
+    }
+}