discovery/multi: move CreateChanAnnouncement to netann

netann/channel_announcement.go

@@ -0,0 +1,81 @@
+package netann
+
+import (
+	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+// CreateChanAnnouncement is a helper function which creates all channel
+// announcements given the necessary channel related database items. This
+// 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 *channeldb.ChannelAuthProof,
+	chanInfo *channeldb.ChannelEdgeInfo,
+	e1, e2 *channeldb.ChannelEdgePolicy) (*lnwire.ChannelAnnouncement,
+	*lnwire.ChannelUpdate, *lnwire.ChannelUpdate, error) {
+
+	// First, using the parameters of the channel, along with the channel
+	// authentication chanProof, we'll create re-create the original
+	// authenticated channel announcement.
+	chanID := lnwire.NewShortChanIDFromInt(chanInfo.ChannelID)
+	chanAnn := &lnwire.ChannelAnnouncement{
+		ShortChannelID:  chanID,
+		NodeID1:         chanInfo.NodeKey1Bytes,
+		NodeID2:         chanInfo.NodeKey2Bytes,
+		ChainHash:       chanInfo.ChainHash,
+		BitcoinKey1:     chanInfo.BitcoinKey1Bytes,
+		BitcoinKey2:     chanInfo.BitcoinKey2Bytes,
+		Features:        lnwire.NewRawFeatureVector(),
+		ExtraOpaqueData: chanInfo.ExtraOpaqueData,
+	}
+
+	var err error
+	chanAnn.BitcoinSig1, err = lnwire.NewSigFromRawSignature(
+		chanProof.BitcoinSig1Bytes,
+	)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	chanAnn.BitcoinSig2, err = lnwire.NewSigFromRawSignature(
+		chanProof.BitcoinSig2Bytes,
+	)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	chanAnn.NodeSig1, err = lnwire.NewSigFromRawSignature(
+		chanProof.NodeSig1Bytes,
+	)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	chanAnn.NodeSig2, err = lnwire.NewSigFromRawSignature(
+		chanProof.NodeSig2Bytes,
+	)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+
+	// We'll unconditionally queue the channel's existence chanProof as it
+	// will need to be processed before either of the channel update
+	// networkMsgs.
+
+	// Since it's up to a node's policy as to whether they advertise the
+	// edge in a direction, we don't create an advertisement if the edge is
+	// nil.
+	var edge1Ann, edge2Ann *lnwire.ChannelUpdate
+	if e1 != nil {
+		edge1Ann, err = ChannelUpdateFromEdge(chanInfo, e1)
+		if err != nil {
+			return nil, nil, nil, err
+		}
+	}
+	if e2 != nil {
+		edge2Ann, err = ChannelUpdateFromEdge(chanInfo, e2)
+		if err != nil {
+			return nil, nil, nil, err
+		}
+	}
+
+	return chanAnn, edge1Ann, edge2Ann, nil
+}