func (dh DataHandler) addInviteeFriendsToInvitee(invitee entities.Invitee) (entities.Invitee, error) { inviteeFriends, err := dh.GetInviteeFriendsFromInviteeID(invitee.InviteeID) if err != nil { return entities.Invitee{}, err } invitee.Friends = inviteeFriends return invitee, nil }