lnwire: shift fields in NodeAnnouncment to match recent BOLT-0007 changes

This commit modifies the NodeAnnouncement message to ensure that it
matches the current spec ordering. The spec was recently modified to
place the feature vector first to allow for future changes to the
fields to be forwards compatible.

lnwire/lnwire_test.go

@@ -384,14 +384,14 @@ func TestLightningWireProtocol(t *testing.T) {
 
 			req := NodeAnnouncement{
 				Signature: testSig,
+				Features:  randFeatureVector(r),
 				Timestamp: uint32(r.Int31()),
-				Alias:     newAlias(a[:]),
+				Alias:     a,
 				RGBColor: RGB{
 					red:   uint8(r.Int31()),
 					green: uint8(r.Int31()),
 					blue:  uint8(r.Int31()),
 				},
-				Features:  randFeatureVector(r),
 				Addresses: testAddrs,
 			}
 			req.Features.featuresMap = nil

lnwire/node_announcement.go

@@ -58,26 +58,25 @@ type NodeAnnouncement struct {
 	// Signature is used to prove the ownership of node id.
 	Signature *btcec.Signature
 
-	// Timestamp allows ordering in the case of multiple
+	// Features is the list of protocol features this node supports.
-	// announcements.
+	Features *FeatureVector
+
+	// Timestamp allows ordering in the case of multiple announcements.
 	Timestamp uint32
 
 	// NodeID is a public key which is used as node identification.
 	NodeID *btcec.PublicKey
 
-	// RGBColor is used to customize their node's appearance in
+	// RGBColor is used to customize their node's appearance in maps and
-	// maps and graphs
+	// graphs
 	RGBColor RGB
 
-
-	// Features is the list of protocol features this node supports.
-	Features *FeatureVector
 	// Alias is used to customize their node's appearance in maps and
 	// graphs
 	Alias NodeAlias
 
-	// Address includes two specification fields: 'ipv6' and 'port' on which
+	// Address includes two specification fields: 'ipv6' and 'port' on
-	// the node is accepting incoming connections.
+	// which the node is accepting incoming connections.
 	Addresses []net.Addr
 }
 
@@ -92,11 +91,11 @@ var _ Message = (*NodeAnnouncement)(nil)
 func (a *NodeAnnouncement) Decode(r io.Reader, pver uint32) error {
 	return readElements(r,
 		&a.Signature,
+		&a.Features,
 		&a.Timestamp,
 		&a.NodeID,
 		&a.RGBColor,
-		&a.Alias,
+		a.Alias[:],
-		&a.Features,
 		&a.Addresses,
 	)
 }
@@ -107,11 +106,11 @@ func (a *NodeAnnouncement) Decode(r io.Reader, pver uint32) error {
 func (a *NodeAnnouncement) Encode(w io.Writer, pver uint32) error {
 	return writeElements(w,
 		a.Signature,
+		a.Features,
 		a.Timestamp,
 		a.NodeID,
 		a.RGBColor,
-		a.Alias,
+		a.Alias[:],
-		a.Features,
 		a.Addresses,
 	)
 }
@@ -138,16 +137,18 @@ func (a *NodeAnnouncement) DataToSign() ([]byte, error) {
 	// We should not include the signatures itself.
 	var w bytes.Buffer
 	err := writeElements(&w,
+		a.Features,
 		a.Timestamp,
 		a.NodeID,
 		a.RGBColor,
-		a.Alias,
+		a.Alias[:],
-		a.Features,
 		a.Addresses,
 	)
 	if err != nil {
 		return nil, err
 	}
 
+	// TODO(roasbeef): also capture the excess bytes in msg padded out?
+
 	return w.Bytes(), nil
 }