Inttroduction

Two things are necessary to explore the functionality of CoreXF: a host application whose functionality is going to be extended and one or more extensions. The following is going to show you how to do that.

CoreXF host application

A .NET Core MVC application can easily be turned into a CoreXF host provided it references CoreXF.Framework package. Few changes have to be made to the Startup class.

The framework has to be added to the existing services like this:

services.AddControllersWithViews().AddCoreXF(services, this.Configuration);

In general, any of the extensions that can be used to configure IServiceCollection and that returns IMvcBuilder would do.

For “using” CoreXF see Registering middleware from extensions.

Please, note that it has to be called just before the call to UseMvc().

CoreXF extension

Extensions come in two main forms:

• plain .NET Core libraries (.DLL), and
• ASP.NET Core MVC applications.

What makes such projects extensions is a class either inheriting from ExtensionBase, or implementing the IExtension interface.

Take a look at he interface:

public interface IExtension
{
    string Name { get; }
    string Description { get; }
    string Url { get; }
    string Version { get; }
    string Authors { get; }
    void ConfigureServices(IServiceCollection services, IConfiguration configuration);
    void ConfigureMiddleware(IExtensionsApplicationBuilder app);
}

and it’s simplest possible implementation:

public class ExtensionBase : IExtension
{
    public virtual string Name => nameof(ExtensionBase);
    public virtual string Description => "Base extension class, inherit to extend functionality.";
    public virtual string Url => "www.codesolidi.com";
    public virtual string Version => "1.0.0";
    public virtual string Authors => "Code Solidi Ltd.";
    public virtual void ConfigureServices(IServiceCollection services, IConfiguration configuration) 
    {
        // source code omitted for brevity
    }
    public virtual void ConfigureMiddleware(IExtensionsApplicationBuilder app)
    {
    }
}

An application or library in which only such a class is defined despite being an extension is still of no use – it has to export some functionality. This functionality may be classified as:

• implementation of an interface known to both the host and the extension,
• one or more controllers with their models and views,
• one or more view components (ViewComponent) with their models and views,
• one or more tag helpers (TagHelper).

Making extensions available to host application

Extensions are added as references directly to the host application. As a matter of fact this is not necessary – extensions can be put in any dedicated folder, say “Extensions” or “Plugins”. This folder must be a subfolder to the main project folder. (NB: This functionality is yet to come!)