Requirements:

• Net5 and higher,
• web browsers with support for websockets.

Contraindications: It is not suitable for those who are tied to HTTP protocol regarding the work with AQB.

Steps to activate:

1. Initialize AQB as usual and add the following lines to the startup.cs file:

services.AddActiveQueryBuilderSignalR();
services.AddSignalR();

app.UseActiveQueryBuilderSignalR();

2. Optionally you can pass the path to the AQB SignalR message handler to the UseActiveQueryBuilderSignalR method. By default AQB uses "/query-builder/handler" path.

3. Implement the IQueryBuilderInstanceFactory to initialize and confugure AQB instances. (Recommedned, but you can also continue using legacy methods.)

4. Create a controller similar to the one that used in the JavaScript demos (just a view, no logic is needed), in the view pass a link to the signalR client (we use this one in our demos: https://cdnjs.cloudflare.com/ajax/libs/microsoft-signalr/6.0.1/signalr.js)

5. Add regular AQB client initialization to the view, plus start of the singalR conneciton:

        $(function () {
            AQB.Web.UI.QueryBuilder(name, $('#qb'));
            AQB.Web.UI.ObjectTreeView(name, $('#treeview'));
            AQB.Web.UI.SubQueryNavigationBar(name, $('#navbar'));
            AQB.Web.UI.Canvas(name, $('#canvas'));
            AQB.Web.UI.StatusBar(name, $('#statusbar'));
            AQB.Web.UI.Grid(name, $('#grid'), { orColumnCount: 0 });
            AQB.Web.UI.SqlEditor(name, $('#sql'));

            const connection = new signalR.HubConnectionBuilder()
               .withUrl("/query-builder/handler")
               .build();

            connection.start().then(() => {
                AQB.Web.UI.useSignalR(connection);
            });
        });

See the SignalR or Blazor demos for details.

Possible pitfall: If you subscribe to AQB events, and access HttpContext in the handler, you get nothing or it will be functionally limited.