public async Task <ActionResult <User> > PostUserGroupAsync([FromBody] UserGroup userGroup)
{
_logger.LogInformation($"Creating user[{userGroup.UserId}] group[{userGroup.GroupId}] connection...");
var(user, group) = await _service.CreateUserGroupAsync(userGroup.UserId, userGroup.GroupId);
await _hubContext.Clients.All.UserJoinedAsync(user.Name, group.Name);
_logger.LogInformation($"Created user[{userGroup.UserId}] group[{userGroup.GroupId}] connection.");
return(_mapper.Map <User>(user));
}