Fix nullable warnings.

src/Microsoft.Identity.Web.UI/Areas/MicrosoftIdentity/Controllers/AccountController.cs

@@ -66,7 +66,7 @@ public IActionResult Challenge(
             string claims)
         {
             string scheme = OpenIdConnectDefaults.AuthenticationScheme;
-            Dictionary<string, string> properties = new Dictionary<string, string>
+            Dictionary<string, string?> properties = new Dictionary<string, string?>
             {
                 { Constants.Scope, scope },
                 { Constants.LoginHint, loginHint },

src/Microsoft.Identity.Web/Constants/IDWebErrorMessage.cs

@@ -8,8 +8,8 @@ namespace Microsoft.Identity.Web
     /// </summary>
     internal static class IDWebErrorMessage
     {
-        // General
-        // public const string IDW10000 = "IDW10000:";
+        // General IDW10000 = "IDW10000:"
+        public const string HttpContextIsNull = "IDW10000: HttpContext is null. ";
 
         // Configuration IDW10100 = "IDW10100:"
         public const string ProvideEitherScopeKeySectionOrScopes = "IDW10101: Either provide the '{0}' or the '{1}' to the 'AuthorizeForScopes'. ";

src/Microsoft.Identity.Web/MicrosoftIdentityCircuitHandler.cs

@@ -15,12 +15,12 @@
 namespace Microsoft.Identity.Web
 {
     /// <summary>
-    /// Extensions for IServiceCollection for startup initialization of web APIs.
+    /// Extensions for IServerSideBlazorBuilder for startup initialization of web APIs.
     /// </summary>
     public static class MicrosoftIdentityBlazorServiceCollectionExtensions
     {
         /// <summary>
-        /// Add the incremental consent and conditional access handler for blazor
+        /// Add the incremental consent and conditional access handler for Blazor
         /// server side pages.
         /// </summary>
         /// <param name="builder">Service side blazor builder.</param>
@@ -55,10 +55,10 @@ public class MicrosoftIdentityConsentAndConditionalAccessHandler
         /// <summary>
         /// Current user.
         /// </summary>
-        public ClaimsPrincipal User { get; internal set; }
+        public ClaimsPrincipal User { get; internal set; } = null!;
 
         /// <summary>
-        /// Base uri to use in forming the redirect.
+        /// Base URI to use in forming the redirect.
         /// </summary>
         public string? BaseUri { get; internal set; }
 
@@ -88,13 +88,13 @@ public void HandleException(Exception exception)
                     User);
 
                 string redirectUri = NavigationManager.Uri;
-                List<string> scope = properties.Parameters.ContainsKey(Constants.Scope) ? (List<string>)properties.Parameters[Constants.Scope] : new List<string>();
-                string loginHint = properties.Parameters.ContainsKey(Constants.LoginHint) ? (string)properties.Parameters[Constants.LoginHint] : string.Empty;
-                string domainHint = properties.Parameters.ContainsKey(Constants.DomainHint) ? (string)properties.Parameters[Constants.DomainHint] : string.Empty;
-                string claims = properties.Parameters.ContainsKey(Constants.Claims) ? (string)properties.Parameters[Constants.Claims] : string.Empty;
+                List<string> scope = properties.Parameters.ContainsKey(Constants.Scope) ? (List<string>)properties.Parameters[Constants.Scope]! : new List<string>();
+                string loginHint = properties.Parameters.ContainsKey(Constants.LoginHint) ? (string)properties.Parameters[Constants.LoginHint]! : string.Empty;
+                string domainHint = properties.Parameters.ContainsKey(Constants.DomainHint) ? (string)properties.Parameters[Constants.DomainHint]! : string.Empty;
+                string claims = properties.Parameters.ContainsKey(Constants.Claims) ? (string)properties.Parameters[Constants.Claims]! : string.Empty;
                 string url = $"{NavigationManager.BaseUri}{Constants.BlazorChallengeUri}{redirectUri}"
-                + $"&{Constants.Scope}={string.Join(" ", scope)}&{Constants.LoginHint}={loginHint}"
-                + $"&{Constants.DomainHint}={domainHint}&{Constants.Claims}={claims}";
+                    + $"&{Constants.Scope}={string.Join(" ", scope!)}&{Constants.LoginHint}={loginHint}"
+                    + $"&{Constants.DomainHint}={domainHint}&{Constants.Claims}={claims}";
 
                 NavigationManager.NavigateTo(url, true);
             }
@@ -104,9 +104,7 @@ public void HandleException(Exception exception)
             }
         }
 
-#pragma warning disable CS8618 // Non-nullable field is uninitialized. Consider declaring as nullable.
-        internal NavigationManager NavigationManager { get; set; }
-#pragma warning restore CS8618 // Non-nullable field is uninitialized. Consider declaring as nullable.
+        internal NavigationManager NavigationManager { get; set; } = null!;
     }
 
 #pragma warning disable SA1402 // File may only contain a single type

src/Microsoft.Identity.Web/ServiceCollectionExtensions.cs

@@ -61,12 +61,12 @@ public static IServiceCollection AddTokenAcquisition(
             if (isTokenAcquisitionSingleton)
             {
                 services.AddSingleton<ITokenAcquisition, TokenAcquisition>();
-                services.AddSingleton<ITokenAcquisitionInternal>(s => (ITokenAcquisitionInternal)s.GetService<ITokenAcquisition>());
+                services.AddSingleton<ITokenAcquisitionInternal>(s => (ITokenAcquisitionInternal)s.GetRequiredService<ITokenAcquisition>());
             }
             else
             {
                 services.AddScoped<ITokenAcquisition, TokenAcquisition>();
-                services.AddScoped<ITokenAcquisitionInternal>(s => (ITokenAcquisitionInternal)s.GetService<ITokenAcquisition>());
+                services.AddScoped<ITokenAcquisitionInternal>(s => (ITokenAcquisitionInternal)s.GetRequiredService<ITokenAcquisition>());
             }
 
             return services;

src/Microsoft.Identity.Web/TokenAcquisition.cs

@@ -36,7 +36,7 @@ internal class TokenAcquisition : ITokenAcquisition, ITokenAcquisitionInternal
 
         private IConfidentialClientApplication? _application;
         private readonly IHttpContextAccessor _httpContextAccessor;
-        private HttpContext CurrentHttpContext => _httpContextAccessor.HttpContext;
+        private HttpContext? CurrentHttpContext => _httpContextAccessor.HttpContext;
         private readonly IMsalHttpClientFactory _httpClientFactory;
         private readonly ILogger _logger;
         private readonly IServiceProvider _serviceProvider;
@@ -270,9 +270,9 @@ public async Task<string> GetAccessTokenForUserAsync(
                 // GetAccessTokenForUserAsync is an abstraction that can be called from a web app or a web API
                 _logger.LogInformation(ex.Message);
 
-                // To get a token for a web API on behalf of the user, but not necessarily with the on behalf of OAuth2.0
-                // flow as this one only applies to web APIs.
-                JwtSecurityToken? validatedToken = CurrentHttpContext.GetTokenUsedToCallWebAPI();
+                // to get a token for a Web API on behalf of the user, but not necessarily with the on behalf of OAuth2.0
+                // flow as this one only applies to Web APIs.
+                JwtSecurityToken? validatedToken = CurrentHttpContext?.GetTokenUsedToCallWebAPI();
 
                 // Case of web APIs: we need to do an on-behalf-of flow
                 if (validatedToken != null)