Update the client authentication results to expose the access token expiration date

src/OpenIddict.Client/OpenIddictClientModels.cs

@@ -66,6 +66,11 @@ public static class OpenIddictClientModels
         /// </summary>
         public required string? BackchannelAccessToken { get; init; }
 
+        /// <summary>
+        /// Gets or sets the expiration date of the backchannel access token, if available.
+        /// </summary>
+        public required DateTimeOffset? BackchannelAccessTokenExpirationDate { get; init; }
+
         /// <summary>
         /// Gets or sets the backchannel identity token, if available.
         /// </summary>
@@ -82,6 +87,11 @@ public static class OpenIddictClientModels
         /// </summary>
         public required string? FrontchannelAccessToken { get; init; }
 
+        /// <summary>
+        /// Gets or sets the expiration date of the frontchannel access token, if available.
+        /// </summary>
+        public required DateTimeOffset? FrontchannelAccessTokenExpirationDate { get; init; }
+
         /// <summary>
         /// Gets or sets the frontchannel identity token, if available.
         /// </summary>
@@ -253,6 +263,11 @@ public static class OpenIddictClientModels
         /// </summary>
         public required string AccessToken { get; init; }
 
+        /// <summary>
+        /// Gets or sets the expiration date of the access token, if available.
+        /// </summary>
+        public required DateTimeOffset? AccessTokenExpirationDate { get; init; }
+
         /// <summary>
         /// Gets or sets the identity token, if available.
         /// </summary>
@@ -394,6 +409,11 @@ public static class OpenIddictClientModels
         /// </summary>
         public required string AccessToken { get; init; }
 
+        /// <summary>
+        /// Gets or sets the expiration date of the access token, if available.
+        /// </summary>
+        public required DateTimeOffset? AccessTokenExpirationDate { get; init; }
+
         /// <summary>
         /// Gets or sets the identity token, if available.
         /// </summary>
@@ -605,6 +625,11 @@ public static class OpenIddictClientModels
         /// </summary>
         public required string AccessToken { get; init; }
 
+        /// <summary>
+        /// Gets or sets the expiration date of the access token, if available.
+        /// </summary>
+        public required DateTimeOffset? AccessTokenExpirationDate { get; init; }
+
         /// <summary>
         /// Gets or sets the identity token, if available.
         /// </summary>
@@ -714,6 +739,11 @@ public static class OpenIddictClientModels
         /// </summary>
         public required string AccessToken { get; init; }
 
+        /// <summary>
+        /// Gets or sets the expiration date of the access token, if available.
+        /// </summary>
+        public required DateTimeOffset? AccessTokenExpirationDate { get; init; }
+
         /// <summary>
         /// Gets or sets the identity token, if available.
         /// </summary>

src/OpenIddict.Client/OpenIddictClientService.cs

@@ -343,9 +343,11 @@ public sealed class OpenIddictClientService
                     AuthorizationCode = context.AuthorizationCode,
                     AuthorizationResponse = context.Request is not null ? new(context.Request.GetParameters()) : new(),
                     BackchannelAccessToken = context.BackchannelAccessToken,
+                    BackchannelAccessTokenExpirationDate = context.BackchannelAccessTokenExpirationDate,
                     BackchannelIdentityToken = context.BackchannelIdentityToken,
                     BackchannelIdentityTokenPrincipal = context.BackchannelIdentityTokenPrincipal,
                     FrontchannelAccessToken = context.FrontchannelAccessToken,
+                    FrontchannelAccessTokenExpirationDate = context.FrontchannelAccessTokenExpirationDate,
                     FrontchannelIdentityToken = context.FrontchannelIdentityToken,
                     FrontchannelIdentityTokenPrincipal = context.FrontchannelIdentityTokenPrincipal,
                     Principal = context.MergedPrincipal,
@@ -590,6 +592,7 @@ public sealed class OpenIddictClientService
             return new()
             {
                 AccessToken = context.BackchannelAccessToken!,
+                AccessTokenExpirationDate = context.BackchannelAccessTokenExpirationDate,
                 IdentityToken = context.BackchannelIdentityToken,
                 IdentityTokenPrincipal = context.BackchannelIdentityTokenPrincipal,
                 Principal = context.MergedPrincipal,
@@ -763,6 +766,7 @@ public sealed class OpenIddictClientService
                         return new()
                         {
                             AccessToken = context.BackchannelAccessToken!,
+                            AccessTokenExpirationDate = context.BackchannelAccessTokenExpirationDate,
                             IdentityToken = context.BackchannelIdentityToken,
                             IdentityTokenPrincipal = context.BackchannelIdentityTokenPrincipal,
                             Principal = context.MergedPrincipal,
@@ -1107,6 +1111,7 @@ public sealed class OpenIddictClientService
             return new()
             {
                 AccessToken = context.BackchannelAccessToken!,
+                AccessTokenExpirationDate = context.BackchannelAccessTokenExpirationDate,
                 IdentityToken = context.BackchannelIdentityToken,
                 IdentityTokenPrincipal = context.BackchannelIdentityTokenPrincipal,
                 Principal = context.MergedPrincipal,
@@ -1268,6 +1273,7 @@ public sealed class OpenIddictClientService
             return new()
             {
                 AccessToken = context.BackchannelAccessToken!,
+                AccessTokenExpirationDate = context.BackchannelAccessTokenExpirationDate,
                 IdentityToken = context.BackchannelIdentityToken,
                 IdentityTokenPrincipal = context.BackchannelIdentityTokenPrincipal,
                 Principal = context.MergedPrincipal,