How to set Duration dynamically for ResponseCacheAttribute

Question

I have a .Net Core 3.1 Web Api application and use the ResponseCache attribute on a controller action.

[HttpGet]
[ResponseCache(Location = ResponseCacheLocation.Any, Duration = 30, VaryByQueryKeys = new[] { "id"})]
public string Get([FromQuery] int id)
{...}

While this is working fine with the hardcoded value for Duration, I need to set this dynamically from the config somehow. I already tried:

• Configuring it in Response Caching Middleware, but then it applies to all controller actions.
• Deriving from ResponseCacheAttribute does not work, as it's internal.

Is there a simple way to achieve what I want, or do I have to write the whole thing (custom ResponseCacheAtrribute + ResponseCacheFilter + ResponseCacheFilterExecutor) by myself ?

Answer 1

I make a new attribute which inherits from the ResponseCacheAttribute which adds most of what I need. For example -

    public class ResponseCacheTillAttribute : ResponseCacheAttribute
    {
        public ResponseCacheTillAttribute(ResponseCacheTime time = ResponseCacheTime.Midnight)
        {
            DateTime today = DateTime.Today;
            switch (time)
            {
                case ResponseCacheTime.Midnight:
                    DateTime midnight = today.AddDays(1).AddSeconds(-1);
                    base.Duration = (int)(midnight - DateTime.Now).TotalSeconds;
                    break;
                default:
                    base.Duration = 30;
                    break;
            }
        }
    }

The Enum looks like

    public enum ResponseCacheTime
    {
        Midnight
    }

This allows me to build in specific times that I may need. I haven't fully tested this but confirmed I see the information in the response output.

You should be able to add any arguments or information you need into the attribute.