Inheritance: Microsoft.AspNetCore.Builder.AuthenticationOptions
        /// <summary>
        /// Adds a new instance of the OAuth2 introspection middleware in the ASP.NET 5 pipeline.
        /// </summary>
        /// <param name="app">The application builder.</param>
        /// <param name="configuration">The delegate used to configure the introspection options.</param>
        /// <returns>The application builder.</returns>
        public static IApplicationBuilder UseOAuthIntrospection(
            [NotNull] this IApplicationBuilder app,
            [NotNull] Action<OAuthIntrospectionOptions> configuration) {
            if (app == null) {
                throw new ArgumentNullException(nameof(app));
            }

            if (configuration == null) {
                throw new ArgumentNullException(nameof(configuration));
            }

            var options = new OAuthIntrospectionOptions();
            configuration(options);

            return app.UseOAuthIntrospection(options);
        }