MediaSharp

Reflection free implementation of Mediator Pattern, as MediatR does.

Using SourceGenerators for generating usefull code for the library, and deleting some boilerplate code :

GitHub - Mediator Source Generator

You can simply add the MediaSharp library in you DI container, that needs to use IServiceCollection at the moment, using services.UseMediaSharp() that is implemented inside MediaSharp.DependencyInjection.

Creating a request

For creating a request you are able to use any class or record (has support for it) doing something like:

public record GetSomethingById(int Id) : IRequest<Something>;

IRequest is accepting any type of class inside the generic at ordinal 0

Creating a RequestHandler

For creating a request handler here is where the source generator kicks in you need to create an IRequestHandler<TRequest, TResult> like :

///This is a mere example

[CallableHandler]
public partial class SomethingRequestHandler : IRequestHandler<GetSomethingById, Something>
{
  // for injecting from DI now the source generator has support for AutoConstructor
  // so we can actually do

  private readonly MyDbContext _dbContext;

  // and the source generator will actually generate a constructor as
  // public SomethingRequestHandler(MediatorContext context, MyDbContext dbContext)
  //{
  //  this._dbContext = dbContext
  //}
  // automatically.

  public async Task<Something> HandleAsync(GetSomethingById request, CancellationToken cancellationToken)
    {
        return await _dbContext.Set<Something>().FirstOrDefaultAsync(x => x.Id == request.Id);
    }
}

Thanks to the CallableHandlerAttribute the source generator has the mark of where you handler is and can proceed to create some boilerplate code for you. Your IRequestHandler<GetSomethingById, Something> must be partial so the generator can extend you class the library won't work if you don't.