How to use SignalR for autorefresh like data

Question

I've been looking into using SignalR for a while now, and I think I have a good candidate for it.

I have a page which allows users of the system to leave Comments, and at the moment it uses JQuery to periodically refresh the list of comments. I think SignalR would replace this nicely, i.e. if there were two users looking at the list and one wrote a comment, I would like it to appear instantly in the second.

All well and good, I have a sort of template where this works.

However

My system itself can sometimes add automatic notifications to the list - These are put into the database directly by a non-web based application.

How can I get SignalR to see the new information from the database and send it to the users?

Answer 1

In SignalR the hub is a static part in your application. You can spin up a System.Threading.Timer in your webapplication to periodically check your database for new notifications and add those to the data used by the hub.

This can even be improved by using a SqlCacheDependency.

A subjective side note: I do agree this type of functionality is a very good candidate for SignalR.