Swashbuckle.AspNetCore DocumentOperationRoleRequirementsFilter

DocumentOperationRoleRequirementsFilter.cs

using Microsoft.AspNetCore.Authorization;
using Swashbuckle.AspNetCore.Swagger;
using Swashbuckle.AspNetCore.SwaggerGen;
using System.Linq;
using System.Reflection;
using System.Web;

namespace MyNameSpace {
    public class DocumentOperationRoleRequirementsFilter : IOperationFilter
    {
        public void Apply(Operation operation, OperationFilterContext context)
        {
            // Get AuthorizeAttribute Roles
            var roles = context.MethodInfo.GetCustomAttributes<AuthorizeAttribute>().Select(a => a.Roles).FirstOrDefault();
            if (!string.IsNullOrEmpty(roles))
            {
                operation.Description = $@"**Roles Required:** {string.Join(", ", roles.Split(',').Select(r => $"<code>{HttpUtility.HtmlEncode(r)}</code>"))}<br/>{operation.Description}";
            }
        }
    }
}