autopilot/interface+agent: remove NodeKey from AttachmentDirective

Instead parse the pubkey bytes only when needed.

autopilot/agent.go

@@ -574,8 +574,13 @@ func (a *Agent) executeDirective(directive AttachmentDirective) {
 
 	// We'll start out by attempting to connect to the peer in order to
 	// begin the funding workflow.
-	pub := directive.NodeKey
 	nodeID := directive.NodeID
+	pub, err := btcec.ParsePubKey(nodeID[:], btcec.S256())
+	if err != nil {
+		log.Errorf("Unable to parse pubkey %x: %v", nodeID, err)
+		return
+	}
+
 	alreadyConnected, err := a.cfg.ConnectToPeer(pub, directive.Addrs)
 	if err != nil {
 		log.Warnf("Unable to connect to %x: %v",

autopilot/agent_test.go

@@ -325,7 +325,6 @@ func TestAgentChannelFailureSignal(t *testing.T) {
 	// request attachment directives, return a fake so the agent will
 	// attempt to open a channel.
 	var fakeDirective = AttachmentDirective{
-		NodeKey: self,
 		NodeID:  NewNodeID(self),
 		ChanAmt: btcutil.SatoshiPerBitcoin,
 		Addrs: []net.Addr{
@@ -669,7 +668,6 @@ func TestAgentImmediateAttach(t *testing.T) {
 		}
 		nodeID := NewNodeID(pub)
 		directives[i] = AttachmentDirective{
-			NodeKey: pub,
 			NodeID:  nodeID,
 			ChanAmt: btcutil.SatoshiPerBitcoin,
 			Addrs: []net.Addr{
@@ -802,7 +800,6 @@ func TestAgentPrivateChannels(t *testing.T) {
 			t.Fatalf("unable to generate key: %v", err)
 		}
 		directives[i] = AttachmentDirective{
-			NodeKey: pub,
 			NodeID:  NewNodeID(pub),
 			ChanAmt: btcutil.SatoshiPerBitcoin,
 			Addrs: []net.Addr{
@@ -925,7 +922,6 @@ func TestAgentPendingChannelState(t *testing.T) {
 	}
 	nodeID := NewNodeID(nodeKey)
 	nodeDirective := AttachmentDirective{
-		NodeKey: nodeKey,
 		NodeID:  nodeID,
 		ChanAmt: 0.5 * btcutil.SatoshiPerBitcoin,
 		Addrs: []net.Addr{
@@ -1309,7 +1305,6 @@ func TestAgentSkipPendingConns(t *testing.T) {
 		t.Fatalf("unable to generate key: %v", err)
 	}
 	nodeDirective := AttachmentDirective{
-		NodeKey: nodeKey,
 		NodeID:  NewNodeID(nodeKey),
 		ChanAmt: 0.5 * btcutil.SatoshiPerBitcoin,
 		Addrs: []net.Addr{

autopilot/interface.go

@@ -85,12 +85,10 @@ type ChannelGraph interface {
 // AttachmentHeuristic. It details to which node a channel should be created
 // to, and also the parameters which should be used in the channel creation.
 type AttachmentDirective struct {
-	// NodeKey is the target node for this attachment directive. It can be
-	// identified by its public key, and therefore can be used along with
-	// a ChannelOpener implementation to execute the directive.
-	NodeKey *btcec.PublicKey
-
-	// NodeID is the serialized compressed pubkey of the target node.
+	// NodeID is the serialized compressed pubkey of the target node for
+	// this attachment directive. It can be identified by its public key,
+	// and therefore can be used along with a ChannelOpener implementation
+	// to execute the directive.
 	NodeID NodeID
 
 	// ChanAmt is the size of the channel that should be opened, expressed

autopilot/prefattach.go

@@ -197,23 +197,15 @@ func (p *ConstrainedPrefAttachment) Select(self *btcec.PublicKey, g ChannelGraph
 		// With the node selected, we'll add this (node, amount) tuple
 		// to out set of recommended directives.
 		pubBytes := selectedNode.PubKey()
-		pub, err := btcec.ParsePubKey(pubBytes[:], btcec.S256())
-		if err != nil {
-			return nil, err
-		}
+		nID := NodeID(pubBytes)
 		directives = append(directives, AttachmentDirective{
-			// TODO(roasbeef): need curve?
-			NodeKey: &btcec.PublicKey{
-				X: pub.X,
-				Y: pub.Y,
-			},
-			NodeID: NewNodeID(pub),
+			NodeID: nID,
 			Addrs:  selectedNode.Addrs(),
 		})
 
 		// With the node selected, we'll add it to the set of visited
 		// nodes to avoid attaching to it again.
-		visited[NodeID(pubBytes)] = struct{}{}
+		visited[nID] = struct{}{}
 	}
 
 	numSelectedNodes := int64(len(directives))

autopilot/prefattach_test.go

@@ -366,11 +366,11 @@ func TestConstrainedPrefAttachmentSelectTwoVertexes(t *testing.T) {
 				edge2Pub := edge2.Peer.PubKey()
 
 				switch {
-				case bytes.Equal(directive.NodeKey.SerializeCompressed(), edge1Pub[:]):
-				case bytes.Equal(directive.NodeKey.SerializeCompressed(), edge2Pub[:]):
+				case bytes.Equal(directive.NodeID[:], edge1Pub[:]):
+				case bytes.Equal(directive.NodeID[:], edge2Pub[:]):
 				default:
 					t1.Fatalf("attached to unknown node: %x",
-						directive.NodeKey.SerializeCompressed())
+						directive.NodeID[:])
 				}
 
 				// As the number of funds available exceed the
@@ -666,8 +666,8 @@ func TestConstrainedPrefAttachmentSelectSkipNodes(t *testing.T) {
 			// We'll simulate a channel update by adding the nodes
 			// we just establish channel with the to set of nodes
 			// to be skipped.
-			skipNodes[NewNodeID(directives[0].NodeKey)] = struct{}{}
-			skipNodes[NewNodeID(directives[1].NodeKey)] = struct{}{}
+			skipNodes[directives[0].NodeID] = struct{}{}
+			skipNodes[directives[1].NodeID] = struct{}{}
 
 			// If we attempt to make a call to the Select function,
 			// without providing any new information, then we