multi: move LightningNode struct to models package

graph/db/models/node.go

@@ -0,0 +1,133 @@
+package models
+
+import (
+	"fmt"
+	"image/color"
+	"net"
+	"time"
+
+	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/btcsuite/btcd/btcec/v2/ecdsa"
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+// LightningNode represents an individual vertex/node within the channel graph.
+// A node is connected to other nodes by one or more channel edges emanating
+// from it. As the graph is directed, a node will also have an incoming edge
+// attached to it for each outgoing edge.
+type LightningNode struct {
+	// PubKeyBytes is the raw bytes of the public key of the target node.
+	PubKeyBytes [33]byte
+	pubKey      *btcec.PublicKey
+
+	// HaveNodeAnnouncement indicates whether we received a node
+	// announcement for this particular node. If true, the remaining fields
+	// will be set, if false only the PubKey is known for this node.
+	HaveNodeAnnouncement bool
+
+	// LastUpdate is the last time the vertex information for this node has
+	// been updated.
+	LastUpdate time.Time
+
+	// Address is the TCP address this node is reachable over.
+	Addresses []net.Addr
+
+	// Color is the selected color for the node.
+	Color color.RGBA
+
+	// Alias is a nick-name for the node. The alias can be used to confirm
+	// a node's identity or to serve as a short ID for an address book.
+	Alias string
+
+	// AuthSigBytes is the raw signature under the advertised public key
+	// which serves to authenticate the attributes announced by this node.
+	AuthSigBytes []byte
+
+	// Features is the list of protocol features supported by this node.
+	Features *lnwire.FeatureVector
+
+	// ExtraOpaqueData is the set of data that was appended to this
+	// message, some of which we may not actually know how to iterate or
+	// parse. By holding onto this data, we ensure that we're able to
+	// properly validate the set of signatures that cover these new fields,
+	// and ensure we're able to make upgrades to the network in a forwards
+	// compatible manner.
+	ExtraOpaqueData []byte
+
+	// TODO(roasbeef): discovery will need storage to keep it's last IP
+	// address and re-announce if interface changes?
+
+	// TODO(roasbeef): add update method and fetch?
+}
+
+// PubKey is the node's long-term identity public key. This key will be used to
+// authenticated any advertisements/updates sent by the node.
+//
+// NOTE: By having this method to access an attribute, we ensure we only need
+// to fully deserialize the pubkey if absolutely necessary.
+func (l *LightningNode) PubKey() (*btcec.PublicKey, error) {
+	if l.pubKey != nil {
+		return l.pubKey, nil
+	}
+
+	key, err := btcec.ParsePubKey(l.PubKeyBytes[:])
+	if err != nil {
+		return nil, err
+	}
+	l.pubKey = key
+
+	return key, nil
+}
+
+// AuthSig is a signature under the advertised public key which serves to
+// authenticate the attributes announced by this node.
+//
+// NOTE: By having this method to access an attribute, we ensure we only need
+// to fully deserialize the signature if absolutely necessary.
+func (l *LightningNode) AuthSig() (*ecdsa.Signature, error) {
+	return ecdsa.ParseSignature(l.AuthSigBytes)
+}
+
+// AddPubKey is a setter-link method that can be used to swap out the public
+// key for a node.
+func (l *LightningNode) AddPubKey(key *btcec.PublicKey) {
+	l.pubKey = key
+	copy(l.PubKeyBytes[:], key.SerializeCompressed())
+}
+
+// NodeAnnouncement retrieves the latest node announcement of the node.
+func (l *LightningNode) NodeAnnouncement(signed bool) (*lnwire.NodeAnnouncement,
+	error) {
+
+	if !l.HaveNodeAnnouncement {
+		return nil, fmt.Errorf("node does not have node announcement")
+	}
+
+	alias, err := lnwire.NewNodeAlias(l.Alias)
+	if err != nil {
+		return nil, err
+	}
+
+	nodeAnn := &lnwire.NodeAnnouncement{
+		Features:        l.Features.RawFeatureVector,
+		NodeID:          l.PubKeyBytes,
+		RGBColor:        l.Color,
+		Alias:           alias,
+		Addresses:       l.Addresses,
+		Timestamp:       uint32(l.LastUpdate.Unix()),
+		ExtraOpaqueData: l.ExtraOpaqueData,
+	}
+
+	if !signed {
+		return nodeAnn, nil
+	}
+
+	sig, err := lnwire.NewSigFromECDSARawSignature(l.AuthSigBytes)
+	if err != nil {
+		return nil, err
+	}
+
+	nodeAnn.Signature = sig
+
+	return nodeAnn, nil
+}