Model interface proposal

model.go

type PayrollModel interface {
  Get(context.Context) (*Payroll, error)
}

func NewPayrollModel(dbx db.SQLExecutor) PayrollModel {
  return &payrollModelImpl{db: db}
}

type payrollModelImpl struct {
  db db.SQLExecutor
}

func (impl *payrollModelImpl) Get(ctx context.Context) (*Payroll, error) {
  impl.db.Select(...).Where(...).ScanStruct(&payroll)
  // etc.
}