lntemp: fix context inheritance

This commit changes how the context is created and inherited to better
reflex the relationship of the components. We now have the following
context structure,
```
For ephemeral nodes, the context chain is,
main HarnessTest -> sub HarnessTest -> HarnessNode -> HarnessRPC

For standby nodes, the context chain is,
main HarnessTest -> standby HarnessNode -> HarnessRPC
```

lntemp/harness.go

@@ -408,9 +408,13 @@ func (h *HarnessTest) SetTestName(name string) {
 func (h *HarnessTest) NewNode(name string,
 	extraArgs []string) *node.HarnessNode {
 
-	node, err := h.manager.newNode(h.T, name, extraArgs, false, nil, false)
+	node, err := h.manager.newNode(h.T, name, extraArgs, nil, false)
 	require.NoErrorf(h, err, "unable to create new node for %s", name)
 
+	// Start the node.
+	err = node.Start(h.runCtx)
+	require.NoError(h, err, "failed to start node %s", node.Name())
+
 	return node
 }
 
@@ -428,7 +432,7 @@ func (h *HarnessTest) Shutdown(node *node.HarnessNode) {
 func (h *HarnessTest) RestartNode(hn *node.HarnessNode,
 	chanBackups ...*lnrpc.ChanBackupSnapshot) {
 
-	err := h.manager.restartNode(hn, nil, chanBackups...)
+	err := h.manager.restartNode(h.runCtx, hn, nil, chanBackups...)
 	require.NoErrorf(h, err, "failed to restart node %s", hn.Name())
 
 	// Give the node some time to catch up with the chain before we

lntemp/harness_node_manager.go

@@ -1,6 +1,7 @@
 package lntemp
 
 import (
+	"context"
 	"fmt"
 	"sync"
 	"sync/atomic"
@@ -70,7 +71,7 @@ func (nm *nodeManager) nextNodeID() uint32 {
 // node can be used immediately. Otherwise, the node will require an additional
 // initialization phase where the wallet is either created or restored.
 func (nm *nodeManager) newNode(t *testing.T, name string, extraArgs []string,
-	useSeed bool, password []byte, cmdOnly bool,
+	password []byte, useSeed bool,
 	opts ...node.Option) (*node.HarnessNode, error) {
 
 	cfg := &node.BaseNodeConfig{
@@ -84,6 +85,7 @@ func (nm *nodeManager) newNode(t *testing.T, name string, extraArgs []string,
 		NodeID:            nm.nextNodeID(),
 		LndBinary:         nm.lndBinary,
 		NetParams:         harnessNetParams,
+		HasSeed:           useSeed,
 	}
 	for _, opt := range opts {
 		opt(cfg)
@@ -96,27 +98,7 @@ func (nm *nodeManager) newNode(t *testing.T, name string, extraArgs []string,
 
 	// Put node in activeNodes to ensure Shutdown is called even if start
 	// returns an error.
-	defer nm.registerNode(node)
-
-	switch {
-	// If the node uses seed to start, we'll need to create the wallet and
-	// unlock the wallet later.
-	case useSeed:
-		err = node.StartWithSeed()
-
-	// Start the node only with the lnd process without creating the grpc
-	// connection, which is used in testing etcd leader selection.
-	case cmdOnly:
-		err = node.StartLndCmd()
-
-	// By default, we'll create a node with wallet being unlocked.
-	default:
-		err = node.Start()
-	}
-
-	if err != nil {
-		return nil, fmt.Errorf("failed to start: %w", err)
-	}
+	nm.registerNode(node)
 
 	return node, nil
 }
@@ -153,10 +135,10 @@ func (nm *nodeManager) shutdownNode(node *node.HarnessNode) error {
 // crashes, etc. Additionally, each time the node is restarted, the caller can
 // pass a set of SCBs to pass in via the Unlock method allowing them to restore
 // channels during restart.
-func (nm *nodeManager) restartNode(node *node.HarnessNode,
+func (nm *nodeManager) restartNode(ctxt context.Context, node *node.HarnessNode,
 	callback func() error, chanBackups ...*lnrpc.ChanBackupSnapshot) error {
 
-	err := nm.restartNodeNoUnlock(node, callback)
+	err := nm.restartNodeNoUnlock(ctxt, node, callback)
 	if err != nil {
 		return err
 	}
@@ -193,8 +175,8 @@ func (nm *nodeManager) restartNode(node *node.HarnessNode,
 // blocking. If the callback parameter is non-nil, then the function will be
 // executed after the node shuts down, but *before* the process has been
 // started up again.
-func (nm *nodeManager) restartNodeNoUnlock(node *node.HarnessNode,
-	callback func() error) error {
+func (nm *nodeManager) restartNodeNoUnlock(ctxt context.Context,
+	node *node.HarnessNode, callback func() error) error {
 
 	if err := node.Stop(); err != nil {
 		return fmt.Errorf("restart node got error: %w", err)
@@ -206,5 +188,9 @@ func (nm *nodeManager) restartNodeNoUnlock(node *node.HarnessNode,
 		}
 	}
 
-	return node.Start()
+	if node.Cfg.HasSeed {
+		return node.StartWithSeed(ctxt)
+	}
+
+	return node.Start(ctxt)
 }

lntemp/node/harness_node.go

@@ -332,9 +332,9 @@ func (hn *HarnessNode) SetExtraArgs(extraArgs []string) {
 
 // StartLndCmd handles the startup of lnd, creating log files, and possibly
 // kills the process when needed.
-func (hn *HarnessNode) StartLndCmd() error {
-	// Init the runCtx.
-	hn.runCtx, hn.cancel = context.WithCancel(context.Background())
+func (hn *HarnessNode) StartLndCmd(ctxb context.Context) error {
+	// Init the run context.
+	hn.runCtx, hn.cancel = context.WithCancel(ctxb)
 
 	args := hn.Cfg.GenArgs()
 	hn.cmd = exec.Command(hn.Cfg.LndBinary, args...) //nolint:gosec
@@ -365,9 +365,9 @@ func (hn *HarnessNode) StartLndCmd() error {
 // start.
 //
 // NOTE: caller needs to take extra step to create and unlock the wallet.
-func (hn *HarnessNode) StartWithSeed() error {
+func (hn *HarnessNode) StartWithSeed(ctxt context.Context) error {
 	// Start lnd process and prepare logs.
-	if err := hn.StartLndCmd(); err != nil {
+	if err := hn.StartLndCmd(ctxt); err != nil {
 		return fmt.Errorf("start lnd error: %w", err)
 	}
 
@@ -388,9 +388,9 @@ func (hn *HarnessNode) StartWithSeed() error {
 
 // Start will start the lnd process, creates the grpc connection, and waits
 // until the server is fully started.
-func (hn *HarnessNode) Start() error {
+func (hn *HarnessNode) Start(ctxt context.Context) error {
 	// Start lnd process and prepare logs.
-	if err := hn.StartLndCmd(); err != nil {
+	if err := hn.StartLndCmd(ctxt); err != nil {
 		return fmt.Errorf("start lnd error: %w", err)
 	}
 
@@ -500,7 +500,7 @@ func (hn *HarnessNode) waitTillServerState(
 func (hn *HarnessNode) initLightningClient() error {
 	// Wait until the server is fully started.
 	if err := hn.WaitUntilServerActive(); err != nil {
-		return err
+		return fmt.Errorf("waiting for server active: %v", err)
 	}
 
 	// Set the harness node's pubkey to what the node claims in GetInfo.
@@ -677,29 +677,36 @@ func (hn *HarnessNode) Stop() error {
 
 	// Close any attempts at further grpc connections.
 	if hn.conn != nil {
-		err := status.Code(hn.conn.Close())
-		switch err {
-		case codes.OK:
-			return nil
-
-		// When the context is canceled above, we might get the
-		// following error as the context is no longer active.
-		case codes.Canceled:
-			return nil
-
-		case codes.Unknown:
-			return fmt.Errorf("unknown error attempting to stop "+
-				"grpc client: %v", err)
-
-		default:
-			return fmt.Errorf("error attempting to stop "+
-				"grpc client: %v", err)
+		if err := hn.CloseConn(); err != nil {
+			return err
 		}
 	}
 
 	return nil
 }
 
+// CloseConn closes the grpc connection.
+func (hn *HarnessNode) CloseConn() error {
+	err := status.Code(hn.conn.Close())
+	switch err {
+	case codes.OK:
+		return nil
+
+	// When the context is canceled above, we might get the
+	// following error as the context is no longer active.
+	case codes.Canceled:
+		return nil
+
+	case codes.Unknown:
+		return fmt.Errorf("unknown error attempting to stop "+
+			"grpc client: %v", err)
+
+	default:
+		return fmt.Errorf("error attempting to stop "+
+			"grpc client: %v", err)
+	}
+}
+
 // Shutdown stops the active lnd process and cleans up any temporary
 // directories created along the way.
 func (hn *HarnessNode) Shutdown() error {