booking-microservices/BuildingBlocks/Web/BaseController.cs

using Asp.Versioning;
using MediatR;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.DependencyInjection;

namespace BuildingBlocks.Web;

using MapsterMapper;

[Route(BaseApiPath)]
[ApiController]
[ApiVersion("1.0")]
public abstract class BaseController : ControllerBase
{
    protected const string BaseApiPath = "api/v{version:apiVersion}";
    private IMapper _mapper;

    private IMediator _mediator;

    protected IMediator Mediator =>
        _mediator ??= HttpContext.RequestServices.GetService<IMediator>();

    protected IMapper Mapper => _mapper ??= HttpContext.RequestServices.GetService<IMapper>();
}