https://docs.microsoft.com/en-us/archive/msdn-magazine/2017/october/cutting-edge-policy-based-authorization-in-asp-net-core

StartupPolicyBasedAuthorization.cs

            #region Authorization Policies
            // We have to first define policies
            services.AddMvcCore(options =>
            {
                var policy = new AuthorizationPolicyBuilder()
                    .RequireAuthenticatedUser()
                    //.RequireClaim("Role", "Test")
                    .Build();
                options.Filters.Add(new AuthorizeFilter(policy));
            });
            // Regi
            services.AddAuthorization(options =>
            {
                options.AddPolicy("TSAdmin", policy =>
                {
                    policy.RequireAuthenticatedUser();
                    policy.RequireClaim("Role", "IT");
                });

                options.AddPolicy("TSUser", policy =>
                {
                    policy.RequireAuthenticatedUser();
                    policy.RequireClaim("Role", "ITs");
                });
            });
            #endregion