c# - How to refresh static class from another website

Question

I have an ASP.Net webform application and ASP.Net WebApi, both are on the same IIS but in different sites and App pools. Both work with the same DB. I have stored some settings values from DB in the static class. Now I need to refresh this static class on the webform app when I change the settings via WebApi and vice versa. I'm using named pipes for sending the flag into the second app 'on setting change'. But I think that named pipes are not 100% reliable. Is there any other (better) mechanism for how to sync these two classes?

question from:https://stackoverflow.com/questions/65951846/how-to-refresh-static-class-from-another-website

Answer 1

There are a number of solutions to this, which one you choose will depend on the frequency of the updates and how critical it is that the data is in sync.

Ideally you should look for a solution that supports your service instances being distributed across multiple physical locations, you will find the overall implementation simpler and it will allow you to scale your solution beyond the current single server

If it is critical that the many instances are in sync, then a WebSocket solution is a proven protocol and design pattern to orchestrate between multiple instances.

At a high level, you define a single server instance that will orchestrate messaging between all the client instances. The clients (your static class) establish a persistent Web Socket connection to the server that the server can use to send messages to the client when they need to refresh the config.

You can do this from first principals following this Asynchronous Server Socket Example but there are implementation frameworks like Signal R that you might find useful as well.

A simpler but less efficient pattern is to simply poll a single source frequently to determine when you need to refresh. The source could be a single timestamp value in a SQL database, or you could use a reliable cloud based storage like MS Azure Tables or Blob storage.

If the call to check for the update is simple and efficient you can usually get away with this without too much effort or causing too much trouble.

Polling can even be more effient in scenarios where the update frequency is high, especially if the updates are more frequent than the times you need to check if the values have changed.

You could also look into a distributed cache, either to replace the whole static class or just to manage the refresh token. Redis Cache is a reliable pattern that is easy to plugin to ASP.Net, you can setup a local Redis server as explained here or you could use a cloud hosted implementation like that offered by Azure