Sitecore 9.2 Dependency Injection in ApiController

Question

I have a standard .net ApiController with the following code:

public class LibraryApiController : ApiController
{
    private readonly ILibraryAssetRepository _repository;

    public LibraryApiController() : this(new LibraryAssetRepository())
    {

    }

    public LibraryApiController(ILibraryAssetRepository repository)
    {
        if(repository == null) throw new ArgumentNullException(nameof(repository));

        _repository = repository;
    }
}

I would like to get rid of the parameterless constructor, but then I run into the dreaded:

An error occurred when trying to create a controller of type 'ApiController'. Make sure that the controller has a parameterless public constructor.

I am using Sitecore's builtin dependency injection (Microsoft.DependencyInjection)

I have only found examples using SitecoreApiControllers. How do I solve this using an ApiController?

Answer 1

As described in this blog post -https://letsdositecore.wordpress.com/2018/11/13/possibly-simplest-way-of-enabling-dependency-injection-in-sitecore-controllers-and-apicontrollers/ , you can use a ServiceConfigurator to register your API controllers using Sitecore DI. Don't forget to patch it in.

namespace Feature.GenericCallout
{
    public class GenericCalloutServicesConfigurator : IServicesConfigurator
    {
        public void Configure(IServiceCollection serviceCollection)
        {
            serviceCollection.AddTransient(typeof(GenericCalloutController));
            serviceCollection.AddTransient(typeof(GenericCalloutApiController));
        }
    }
}