type DeleteProductService struct {
}

func (service *DeleteProductService) Delete(id string) serializer.Response {
...
}

deleteProductService := service.DeleteProductService{}

deleteProductService := service.DeleteProductService{}

c.JSON(200, res)

func DeleteProduct(c *gin.Context) {
    deleteProductService := service.DeleteProductService{}
    res := deleteProductService.Delete(c.Param("id"))
    c.JSON(200, res)
}

var product model.Product
    err := model.DB.First(&product, id).Error

err = model.DB.Delete(&product).Error

return serializer.Response{
  Status: code,
  Msg:    e.GetMsg(code),
    }