discovery

type Discovery interface {
	CreateOffer(ctx context.Context, fromNode *types.Node, toNode *types.Node, offer *types.Offer)
	RefreshOffer(ctx context.Context, fromTrader *types.Node, offer *types.Offer) bool
	RemoveOffer(ctx context.Context, fromSupp *types.Node, toTrader *types.Node, offer *types.Offer)
	GetOffers(ctx context.Context, fromNode, toTrader *types.Node, relay bool) []types.AvailableOffer
	AdvertiseOffersNeighbor(ctx context.Context, fromTrader, toNeighborTrader, traderOffering *types.Node)
}