multi: add ToChannelAnnouncement helper on ChannelEdgeInfo

So that we have one place that converts from our `models` struct to the
`lnwire.ChannelAnnouncement` struct.

The commit also refactors netann.CreateChanAnnouncement to only take a
ChannelEdgeInfo and get the proof from there instead of needing the
proof to be passed in separately.

Author: ellemouton

discovery/chan_series.go

@@ -133,8 +133,7 @@ func (c *ChanSeries) UpdatesInHorizon(chain chainhash.Hash,
 
 			//nolint:ll
 			chanAnn, edge1, edge2, err := netann.CreateChanAnnouncement(
-				channel.Info.AuthProof, channel.Info,
-				channel.Policy1, channel.Policy2,
+				channel.Info, channel.Policy1, channel.Policy2,
 			)
 			if err != nil {
 				if !yield(nil, err) {
@@ -281,8 +280,7 @@ func (c *ChanSeries) FetchChanAnns(chain chainhash.Hash,
 		}
 
 		chanAnn, edge1, edge2, err := netann.CreateChanAnnouncement(
-			channel.Info.AuthProof, channel.Info, channel.Policy1,
-			channel.Policy2,
+			channel.Info, channel.Policy1, channel.Policy2,
 		)
 		if err != nil {
 			return nil, err

discovery/gossiper.go

@@ -1996,10 +1996,14 @@ func (d *AuthenticatedGossiper) processRejectedEdge(_ context.Context,
 		return nil, nil
 	}
 
+	// Attach the proof to the channel info before creating the
+	// announcement.
+	chanInfo.AuthProof = proof
+
 	// We'll then create then validate the new fully assembled
 	// announcement.
 	chanAnn, e1Ann, e2Ann, err := netann.CreateChanAnnouncement(
-		proof, chanInfo, e1, e2,
+		chanInfo, e1, e2,
 	)
 	if err != nil {
 		return nil, err
@@ -2392,44 +2396,13 @@ func (d *AuthenticatedGossiper) updateChannel(ctx context.Context,
 	// have a full channel announcement for this channel.
 	var chanAnn *lnwire.ChannelAnnouncement1
 	if info.AuthProof != nil {
-		chanID := lnwire.NewShortChanIDFromInt(info.ChannelID)
-		chanAnn = &lnwire.ChannelAnnouncement1{
-			ShortChannelID:  chanID,
-			NodeID1:         info.NodeKey1Bytes,
-			NodeID2:         info.NodeKey2Bytes,
-			ChainHash:       info.ChainHash,
-			BitcoinKey1:     info.BitcoinKey1Bytes,
-			Features:        lnwire.NewRawFeatureVector(),
-			BitcoinKey2:     info.BitcoinKey2Bytes,
-			ExtraOpaqueData: info.ExtraOpaqueData,
-		}
-		chanAnn.NodeSig1, err = lnwire.NewSigFromECDSARawSignature(
-			info.AuthProof.NodeSig1(),
-		)
-		if err != nil {
-			return nil, nil, err
-		}
-		chanAnn.NodeSig2, err = lnwire.NewSigFromECDSARawSignature(
-			info.AuthProof.NodeSig2(),
-		)
-		if err != nil {
-			return nil, nil, err
-		}
-		chanAnn.BitcoinSig1, err = lnwire.NewSigFromECDSARawSignature(
-			info.AuthProof.BitcoinSig1(),
-		)
-		if err != nil {
-			return nil, nil, err
-		}
-		chanAnn.BitcoinSig2, err = lnwire.NewSigFromECDSARawSignature(
-			info.AuthProof.BitcoinSig2(),
-		)
+		chanAnn, err = info.ToChannelAnnouncement()
 		if err != nil {
 			return nil, nil, err
 		}
 	}
 
-	return chanAnn, chanUpdate, err
+	return chanAnn, chanUpdate, nil
 }
 
 // SyncManager returns the gossiper's SyncManager instance.
@@ -3570,7 +3543,7 @@ func (d *AuthenticatedGossiper) handleAnnSig(ctx context.Context,
 					ann.ChannelID, peerID)
 
 				ca, _, _, err := netann.CreateChanAnnouncement(
-					chanInfo.AuthProof, chanInfo, e1, e2,
+					chanInfo, e1, e2,
 				)
 				if err != nil {
 					log.Errorf("unable to gen ann: %v",
@@ -3649,8 +3622,12 @@ func (d *AuthenticatedGossiper) handleAnnSig(ctx context.Context,
 		)
 	}
 
+	// Attach the proof to the channel info before creating the
+	// announcement.
+	chanInfo.AuthProof = dbProof
+
 	chanAnn, e1Ann, e2Ann, err := netann.CreateChanAnnouncement(
-		dbProof, chanInfo, e1, e2,
+		chanInfo, e1, e2,
 	)
 	if err != nil {
 		log.Error(err)

graph/db/models/channel_edge_info.go

@@ -220,3 +220,66 @@ func (c *ChannelEdgeInfo) OtherNodeKeyBytes(thisNodeKey []byte) (
 			"this channel")
 	}
 }
+
+// ToChannelAnnouncement converts the ChannelEdgeInfo to a
+// lnwire.ChannelAnnouncement1 message. Returns an error if AuthProof is nil
+// or if the version is not v1.
+func (c *ChannelEdgeInfo) ToChannelAnnouncement() (
+	*lnwire.ChannelAnnouncement1, error) {
+
+	// We currently only support v1 channel announcements.
+	if c.Version != lnwire.GossipVersion1 {
+		return nil, fmt.Errorf("unsupported channel version: %d",
+			c.Version)
+	}
+
+	// If there's no auth proof, we can't create a full channel
+	// announcement.
+	if c.AuthProof == nil {
+		return nil, fmt.Errorf("cannot create channel announcement " +
+			"without auth proof")
+	}
+
+	chanID := lnwire.NewShortChanIDFromInt(c.ChannelID)
+	chanAnn := &lnwire.ChannelAnnouncement1{
+		ShortChannelID:  chanID,
+		NodeID1:         c.NodeKey1Bytes,
+		NodeID2:         c.NodeKey2Bytes,
+		ChainHash:       c.ChainHash,
+		BitcoinKey1:     c.BitcoinKey1Bytes,
+		BitcoinKey2:     c.BitcoinKey2Bytes,
+		Features:        c.Features.RawFeatureVector,
+		ExtraOpaqueData: c.ExtraOpaqueData,
+	}
+
+	var err error
+	chanAnn.NodeSig1, err = lnwire.NewSigFromECDSARawSignature(
+		c.AuthProof.NodeSig1(),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	chanAnn.NodeSig2, err = lnwire.NewSigFromECDSARawSignature(
+		c.AuthProof.NodeSig2(),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	chanAnn.BitcoinSig1, err = lnwire.NewSigFromECDSARawSignature(
+		c.AuthProof.BitcoinSig1(),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	chanAnn.BitcoinSig2, err = lnwire.NewSigFromECDSARawSignature(
+		c.AuthProof.BitcoinSig2(),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return chanAnn, nil
+}

netann/channel_announcement.go

@@ -34,48 +34,14 @@ const (
 // function is used to transform out database structs into the corresponding wire
 // structs for announcing new channels to other peers, or simply syncing up a
 // peer's initial routing table upon connect.
-func CreateChanAnnouncement(chanProof *models.ChannelAuthProof,
-	chanInfo *models.ChannelEdgeInfo,
+func CreateChanAnnouncement(chanInfo *models.ChannelEdgeInfo,
 	e1, e2 *models.ChannelEdgePolicy) (*lnwire.ChannelAnnouncement1,
 	*lnwire.ChannelUpdate1, *lnwire.ChannelUpdate1, error) {
 
 	// First, using the parameters of the channel, along with the channel
-	// authentication chanProof, we'll create re-create the original
+	// authentication proof, we'll create re-create the original
 	// authenticated channel announcement.
-	chanID := lnwire.NewShortChanIDFromInt(chanInfo.ChannelID)
-	chanAnn := &lnwire.ChannelAnnouncement1{
-		ShortChannelID:  chanID,
-		NodeID1:         chanInfo.NodeKey1Bytes,
-		NodeID2:         chanInfo.NodeKey2Bytes,
-		ChainHash:       chanInfo.ChainHash,
-		BitcoinKey1:     chanInfo.BitcoinKey1Bytes,
-		BitcoinKey2:     chanInfo.BitcoinKey2Bytes,
-		Features:        chanInfo.Features.RawFeatureVector,
-		ExtraOpaqueData: chanInfo.ExtraOpaqueData,
-	}
-
-	var err error
-	chanAnn.BitcoinSig1, err = lnwire.NewSigFromECDSARawSignature(
-		chanProof.BitcoinSig1(),
-	)
-	if err != nil {
-		return nil, nil, nil, err
-	}
-	chanAnn.BitcoinSig2, err = lnwire.NewSigFromECDSARawSignature(
-		chanProof.BitcoinSig2(),
-	)
-	if err != nil {
-		return nil, nil, nil, err
-	}
-	chanAnn.NodeSig1, err = lnwire.NewSigFromECDSARawSignature(
-		chanProof.NodeSig1(),
-	)
-	if err != nil {
-		return nil, nil, nil, err
-	}
-	chanAnn.NodeSig2, err = lnwire.NewSigFromECDSARawSignature(
-		chanProof.NodeSig2(),
-	)
+	chanAnn, err := chanInfo.ToChannelAnnouncement()
 	if err != nil {
 		return nil, nil, nil, err
 	}

netann/channel_announcement_test.go

@@ -62,9 +62,7 @@ func TestCreateChanAnnouncement(t *testing.T) {
 		models.WithFeatures(features),
 	)
 	require.NoError(t, err)
-	chanAnn, _, _, err := CreateChanAnnouncement(
-		chanProof, chanInfo, nil, nil,
-	)
+	chanAnn, _, _, err := CreateChanAnnouncement(chanInfo, nil, nil)
 	require.NoError(t, err, "unable to create channel announcement")
 
 	assert.Equal(t, chanAnn, expChanAnn)