lnd: use saved node ann data from previous run

This commit ensures that we start with the alias, node color,
addresses, and features as advertised in the node's previous
runtime. This approach maintains consistency in the node's
advertised information across restarts.

Author: Abdulkbk

server.go

@@ -6,6 +6,7 @@ import (
 	"crypto/rand"
 	"encoding/hex"
 	"fmt"
+	"image/color"
 	"math/big"
 	prand "math/rand"
 	"net"
@@ -803,33 +804,74 @@ func newServer(cfg *Config, listenAddrs []net.Addr,
 	// replicate it, and instead it'll only be stored locally.
 	chanGraph := dbs.GraphDB.ChannelGraph()
 
+	// Fetch the source node from the channel graph. If a source node is
+	// found, we'll use its values for our initial node announcement.
+	persistedNode, err := chanGraph.SourceNode()
+	if err != nil {
+		srvrLog.Errorf("unable to fetch source node: %v", err)
+	}
+
 	// We'll now reconstruct a node announcement based on our current
 	// configuration so we can send it out as a sort of heart beat within
 	// the network.
 	//
-	// We'll start by parsing the node color from configuration.
-	color, err := lncfg.ParseHexColor(cfg.Color)
-	if err != nil {
-		srvrLog.Errorf("unable to parse color: %v\n", err)
-		return nil, err
-	}
 
-	// If no alias is provided, default to first 10 characters of public
-	// key.
-	alias := cfg.Alias
-	if alias == "" {
-		alias = hex.EncodeToString(serializedPubKey[:10])
+	// If the node is restarted, we should use the previously persisted
+	// values for the node's alias, color, addresses, and features.
+	// Otherwise, we'll use the configured values.
+	var (
+		color    color.RGBA
+		alias    = cfg.Alias
+		features *lnwire.FeatureVector
+	)
+
+	// If the node was previously persisted, we'll use the saved values.
+	if persistedNode != nil {
+		// If the color is still set to the default, we'll use the
+		// persisted color.
+		if cfg.Color == defaultColor {
+			color = persistedNode.Color
+		}
+
+		// If an alias was not specified in the configuration,
+		// we'll use the saved alias.
+		if alias == "" {
+			alias = persistedNode.Alias
+		}
+
+		features = persistedNode.Features
+
+		// Append the persisted addresses to the list of addresses our
+		// node can be reached at.
+		selfAddrs = append(selfAddrs, persistedNode.Addresses...)
+	} else {
+		color, err = lncfg.ParseHexColor(cfg.Color)
+		if err != nil {
+			srvrLog.Errorf("unable to parse color: %v\n", err)
+
+			return nil, err
+		}
+
+		// If an alias was not specified, we'll generate one based on
+		// the serialized public key.
+		if alias == "" {
+			alias = hex.EncodeToString(serializedPubKey[:10])
+		}
+
+		features = s.featureMgr.Get(feature.SetNodeAnn)
 	}
+
 	nodeAlias, err := lnwire.NewNodeAlias(alias)
 	if err != nil {
 		return nil, err
 	}
+
 	selfNode := &channeldb.LightningNode{
 		HaveNodeAnnouncement: true,
 		LastUpdate:           time.Now(),
 		Addresses:            selfAddrs,
 		Alias:                nodeAlias.String(),
-		Features:             s.featureMgr.Get(feature.SetNodeAnn),
+		Features:             features,
 		Color:                color,
 	}
 	copy(selfNode.PubKeyBytes[:], nodeKeyDesc.PubKey.SerializeCompressed())