For year we have been using the outdated notion of controllers in ASP.NET to build our web APIs. However, the controller itself doesn't serve much of a purpose, other than to group together a bunch of methods that maybe share some bits of routing information. Recently, the mediator pattern has caught on, causing us to write a lot of boilerplate code like:
public class MyController : ApiController
{
private readonly ICommandBus _commandBus;
public MyController(ICommandBus commandBus)
{
_commandBus = commandBus;
}
[HttpGet("/something/{id}")]
public IActionResult GetSomethingApi(int id)
{
var command = new GetSomethingCommand { Id = id };
return _commandBus.Invoke(command);
}
}Assuming your API has more than one endpoint/command, that's a lot of boilerplate code just to fire off commands and return the result. Commandr aims to solve that problem by extending ASP.NET Core's endpoint routing feature to bind directly to a command, and then execute the command for you. No more controllers, ever.
The result is a project that is smaller, cleaner, and in my opinion a lot easier to test because you can simply write unit tests for your command handlers and not worry about creating controllers and all the ceremony therein.
I've been a fan of Jasper, and I have produced a simple example that ends up being very little code compared to a similar project using MVC controllers. Commandr, however, aims to be agnostic as to which of the messaging/command stacks you choose. Commandr could just as easily work with Mediatr, or you could even write your own simple executor if you want.
As stated above, Commandr is in it's infancy, so there's still a lot of work to do. The ultimate goal is for it to be a drop-in replacement for ASP.NET MVC for web APIs (it will never try to replace Razor/Blazor).
Would love to hear your thoughts and ideas!