graph/db: add FundingPKScript method on ChannelEdgeInfo

Author: ellemouton

graph/db/kv_store.go

@@ -4113,15 +4113,7 @@ func (c *KVStore) ChannelView() ([]EdgePoint, error) {
 					return err
 				}
 
-				btcKey1 := edgeInfo.BitcoinKey1Bytes.UnwrapOr(
-					route.Vertex{},
-				)
-				btcKey2 := edgeInfo.BitcoinKey2Bytes.UnwrapOr(
-					route.Vertex{},
-				)
-				pkScript, err := genMultiSigP2WSH(
-					btcKey1[:], btcKey2[:],
-				)
+				pkScript, err := edgeInfo.FundingPKScript()
 				if err != nil {
 					return err
 				}

graph/db/models/channel_edge_info.go

@@ -9,6 +9,7 @@ import (
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightningnetwork/lnd/fn/v2"
+	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/routing/route"
 )
@@ -221,6 +222,38 @@ func (c *ChannelEdgeInfo) OtherNodeKeyBytes(thisNodeKey []byte) (
 	}
 }
 
+// FundingPKScript returns the funding output's pkScript for the channel.
+func (c *ChannelEdgeInfo) FundingPKScript() ([]byte, error) {
+	switch c.Version {
+	case lnwire.GossipVersion1:
+		btc1Key, err := c.BitcoinKey1Bytes.UnwrapOrErr(
+			fmt.Errorf("missing bitcoin key 1"),
+		)
+		if err != nil {
+			return nil, err
+		}
+		btc2Key, err := c.BitcoinKey2Bytes.UnwrapOrErr(
+			fmt.Errorf("missing bitcoin key 2"),
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		witnessScript, err := input.GenMultiSigScript(
+			btc1Key[:], btc2Key[:],
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		return input.WitnessScriptHash(witnessScript)
+
+	default:
+		return nil, fmt.Errorf("unsupported channel version: %d",
+			c.Version)
+	}
+}
+
 // ToChannelAnnouncement converts the ChannelEdgeInfo to a
 // lnwire.ChannelAnnouncement1 message. Returns an error if AuthProof is nil
 // or if the version is not v1.

graph/db/sql_store.go

@@ -2761,6 +2761,7 @@ func (s *SQLStore) ChannelView() ([]EdgePoint, error) {
 		handleChannel := func(_ context.Context,
 			channel sqlc.ListChannelsPaginatedRow) error {
 
+			// TODO(elle): update to handle V2 channels.
 			pkScript, err := genMultiSigP2WSH(
 				channel.BitcoinKey1, channel.BitcoinKey2,
 			)