Dependency injection of context class in constructor

I your controller have for example only one method then introduction of separate constructor just for saving ApplicationContext have no advantage. The context will be already hold inside of the HttpContext and you can use [FromServices] attribute as the additional parameter of your controller action. See the documentation. For example

[Route("api/[controller]")]
public class MyController : Controller
{
    [HttpGet]
    public async IEnumerable<object> Get([FromServices] ApplicationContext context,
                                         MyType myMainParam)
    {
        ...
    }
}

RC1 allows to define property with [FromServices] for getting the information from dependency injection, but RC2 will don't more allow this (see the announcement). You can find examples of both styles in the answer.