rfq: replace asset ID and group key with asset specifier in SellOrder

Refactor SellOrder by replacing the fields "asset ID" and "asset
group key" with a single "asset specifier" field for simplicity
and consistency.

Author: ffranr

rfq/manager.go

@@ -747,11 +747,8 @@ func (m *Manager) UpsertAssetBuyOrder(order BuyOrder) error {
 
 // SellOrder is a struct that represents an asset sell order.
 type SellOrder struct {
-	// AssetID is the ID of the asset to sell.
-	AssetID *asset.ID
-
-	// AssetGroupKey is the public key of the asset group to sell.
-	AssetGroupKey *btcec.PublicKey
+	// AssetSpecifier is the asset that the seller is interested in.
+	AssetSpecifier asset.Specifier
 
 	// PaymentMaxAmt is the maximum msat amount that the responding peer
 	// must agree to pay.

rfq/negotiator.go

@@ -472,21 +472,10 @@ func (n *Negotiator) HandleOutgoingSellOrder(order SellOrder) {
 		// skip this step.
 		var assetRateHint fn.Option[rfqmsg.AssetRate]
 
-		// Construct an asset specifier from the order.
-		// TODO(ffranr): The order should have an asset specifier.
-		assetSpecifier, err := asset.NewSpecifier(
-			order.AssetID, order.AssetGroupKey, nil,
-			true,
-		)
-		if err != nil {
-			log.Warnf("failed to construct asset "+
-				"specifier from buy order: %v", err)
-		}
-
-		if n.cfg.PriceOracle != nil && assetSpecifier.IsSome() {
+		if n.cfg.PriceOracle != nil && order.AssetSpecifier.IsSome() {
 			// Query the price oracle for an asking price.
 			assetRate, err := n.queryAskFromPriceOracle(
-				order.Peer, assetSpecifier,
+				order.Peer, order.AssetSpecifier,
 				fn.None[uint64](),
 				fn.Some(order.PaymentMaxAmt),
 				fn.None[rfqmsg.AssetRate](),
@@ -502,8 +491,8 @@ func (n *Negotiator) HandleOutgoingSellOrder(order SellOrder) {
 		}
 
 		request, err := rfqmsg.NewSellRequest(
-			*order.Peer, order.AssetID, order.AssetGroupKey,
-			order.PaymentMaxAmt, assetRateHint,
+			*order.Peer, order.AssetSpecifier, order.PaymentMaxAmt,
+			assetRateHint,
 		)
 		if err != nil {
 			err := fmt.Errorf("unable to create sell request "+

rfqmsg/sell_request.go

@@ -45,23 +45,15 @@ type SellRequest struct {
 }
 
 // NewSellRequest creates a new asset sell quote request.
-func NewSellRequest(peer route.Vertex, assetID *asset.ID,
-	assetGroupKey *btcec.PublicKey, paymentMaxAmt lnwire.MilliSatoshi,
+func NewSellRequest(peer route.Vertex, assetSpecifier asset.Specifier,
+	paymentMaxAmt lnwire.MilliSatoshi,
 	assetRateHint fn.Option[AssetRate]) (*SellRequest, error) {
 
 	id, err := NewID()
 	if err != nil {
 		return nil, fmt.Errorf("unable to generate random id: %w", err)
 	}
 
-	assetSpecifier, err := asset.NewSpecifier(
-		assetID, assetGroupKey, nil, true,
-	)
-	if err != nil {
-		return nil, fmt.Errorf("unable to create asset specifier: %w",
-			err)
-	}
-
 	return &SellRequest{
 		Peer:           peer,
 		Version:        latestSellRequestVersion,

rpcserver.go

@@ -6414,11 +6414,19 @@ func unmarshalAssetSellOrder(
 		peer = &pv
 	}
 
+	// Construct an asset specifier from the asset ID and/or group key.
+	assetSpecifier, err := asset.NewSpecifier(
+		assetId, assetGroupKey, nil, true,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("error creating asset specifier: %w",
+			err)
+	}
+
 	return &rfq.SellOrder{
-		AssetID:       assetId,
-		AssetGroupKey: assetGroupKey,
-		PaymentMaxAmt: lnwire.MilliSatoshi(req.PaymentMaxAmt),
-		Peer:          peer,
+		AssetSpecifier: assetSpecifier,
+		PaymentMaxAmt:  lnwire.MilliSatoshi(req.PaymentMaxAmt),
+		Peer:           peer,
 	}, nil
 }