fix(is): service resolution from HttpContext

Fix service resolution in PostConfigureApplicationCookieTicketStore so that it can be
constructed without an http context available.

src/IdentityServer/Configuration/DependencyInjection/PostConfigureApplicationCookieTicketStore.cs

@@ -21,7 +21,6 @@ public class PostConfigureApplicationCookieTicketStore : IPostConfigureOptions<C
 {
     private readonly IHttpContextAccessor _httpContextAccessor;
     private readonly string _scheme;
-    private readonly LicenseUsageTracker _licenseUsage;
     private readonly ILogger<PostConfigureApplicationCookieTicketStore> _logger;
 
     /// <summary>
@@ -38,7 +37,6 @@ public PostConfigureApplicationCookieTicketStore(
         ILogger<PostConfigureApplicationCookieTicketStore> logger)
     {
         _httpContextAccessor = httpContextAccessor;
-        _licenseUsage = httpContextAccessor.HttpContext?.RequestServices.GetRequiredService<LicenseUsageTracker>();
         _logger = logger;
 
         _scheme = identityServerOptions.Authentication.CookieAuthenticationScheme ??
@@ -69,6 +67,7 @@ public void PostConfigure(string name, CookieAuthenticationOptions options)
             }
 
             IdentityServerLicenseValidator.Instance.ValidateServerSideSessions();
+            var _licenseUsage = _httpContextAccessor.HttpContext?.RequestServices.GetRequiredService<LicenseUsageTracker>();
             _licenseUsage.FeatureUsed(LicenseFeature.ServerSideSessions);
 
             var sessionStore = _httpContextAccessor.HttpContext!.RequestServices.GetService<IServerSideSessionStore>();

test/IdentityServer.UnitTests/Common/MockHttpContextAccessor.cs

@@ -2,6 +2,7 @@
 // See LICENSE in the project root for license information.
 
 
+using System;
 using Duende.IdentityServer;
 using Duende.IdentityServer.Configuration;
 using Duende.IdentityServer.Models;
@@ -24,7 +25,8 @@ public MockHttpContextAccessor(
         IdentityServerOptions options = null,
         IUserSession userSession = null,
         IMessageStore<LogoutNotificationContext> endSessionStore = null,
-        IServerUrls urls = null)
+        IServerUrls urls = null,
+        Action<ServiceCollection> configureServices = null)
     {
         options = options ?? TestIdentityServerOptions.Create();
 
@@ -63,6 +65,11 @@ public MockHttpContextAccessor(
             services.AddSingleton<IServerUrls>(urls);
         }
 
+        if (configureServices != null)
+        {
+            configureServices(services);
+        }
+
         _context.RequestServices = services.BuildServiceProvider();
     }
 

test/IdentityServer.UnitTests/Configuration/DependencyInjection/PostConfigureApplicationCookieTicketStoreTests.cs

@@ -0,0 +1,53 @@
+using Duende.IdentityServer.Configuration;
+using Duende.IdentityServer.Licensing.V2;
+using FluentAssertions;
+using Microsoft.AspNetCore.Authentication.Cookies;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Options;
+using UnitTests.Common;
+using Xunit;
+
+namespace UnitTests.Configuration.DependencyInjection;
+
+public class PostConfigureApplicationCookieTicketStoreTests
+{
+
+    [Fact]
+    public void can_be_constructed_without_httpcontext_and_used_later_with_httpcontext()
+    {
+        // Register the dependencies of the usage tracker so that we can resolve it in PostConfigure
+        var httpContextAccessor = new MockHttpContextAccessor(configureServices: sp =>
+        {
+            sp.AddSingleton(TestLogger.Create<LicenseAccessor>());
+            sp.AddSingleton<LicenseAccessor>();
+            sp.AddSingleton<LicenseUsageTracker>();
+        });
+
+        // The mock http context has a convenient HttpContext, but initially we
+        // simulate not having it by stashing it away and setting the accessor
+        // to null.
+        var savedContext = httpContextAccessor.HttpContext; 
+        httpContextAccessor.HttpContext = null;
+
+        var sut = new PostConfigureApplicationCookieTicketStore(
+            httpContextAccessor,
+            new IdentityServerOptions
+            {
+                Authentication = new AuthenticationOptions 
+                {
+                    // This is needed so that we operate on the correct scheme
+                    CookieAuthenticationScheme = CookieAuthenticationDefaults.AuthenticationScheme 
+                }
+            },
+            Options.Create<Microsoft.AspNetCore.Authentication.AuthenticationOptions>(new()),
+            TestLogger.Create<PostConfigureApplicationCookieTicketStore>()
+        );
+
+        // Now that we've constructed, we can bring back the http context and run PostConfigure
+        httpContextAccessor.HttpContext = savedContext;
+        var cookieOpts = new CookieAuthenticationOptions();
+        sut.PostConfigure(CookieAuthenticationDefaults.AuthenticationScheme, cookieOpts);
+
+        cookieOpts.SessionStore.Should().BeOfType<TicketStoreShim>();
+    }
+}