presence_sample_v2/Presence.Api/Controllers/GroupController.cs

using domain.Service;
using domain.UseCase;
using Microsoft.AspNetCore.Mvc;
using Presence.Api.Response;

namespace Presence.Api.Controllers
{
    [ApiController]
    [Route("api/[contrtoller]")]
    public class GroupController: ControllerBase
    {
        private readonly IGroupUseCase _groupService;

        public GroupController(IGroupUseCase groupService) { 
            _groupService = groupService;
        }

        [HttpGet("/group")]
        public async Task<ActionResult<GroupResponse>> GetAllGroups() {

            var result = await _groupService
                .GetGroupsWithStudentsAsync();
            var response = result
                .Select(group => new GroupResponse { 
                    Id = group.Id, 
                    Name = group.Name,
                    Users = group.Users?.Select(
                        user => new UserResponse { 
                            Guid = user.Guid,
                            Name =  user.Name, 
                        }).ToList()
                }).ToList();
            return Ok(result);

        }
    }
}