itest: add etcd flag to control if new lnd nodes should run on etcd

lntest/harness.go

@@ -60,6 +60,10 @@ type NetworkHarness struct {
 	Alice *HarnessNode
 	Bob   *HarnessNode
 
+	// useEtcd is set to true if new nodes are to be created with an
+	// embedded etcd backend instead of just bbolt.
+	useEtcd bool
+
 	// Channel for transmitting stderr output from failed lightning node
 	// to main process.
 	lndErrorChan chan error
@@ -77,8 +81,8 @@ type NetworkHarness struct {
 // TODO(roasbeef): add option to use golang's build library to a binary of the
 // current repo. This will save developers from having to manually `go install`
 // within the repo each time before changes
-func NewNetworkHarness(r *rpctest.Harness, b BackendConfig, lndBinary string) (
+func NewNetworkHarness(r *rpctest.Harness, b BackendConfig, lndBinary string,
-	*NetworkHarness, error) {
+	useEtcd bool) (*NetworkHarness, error) {
 
 	feeService := startFeeService()
 
@@ -92,6 +96,7 @@ func NewNetworkHarness(r *rpctest.Harness, b BackendConfig, lndBinary string) (
 		feeService:   feeService,
 		quit:         make(chan struct{}),
 		lndBinary:    lndBinary,
+		useEtcd:      useEtcd,
 	}
 	return &n, nil
 }
@@ -376,6 +381,7 @@ func (n *NetworkHarness) newNode(name string, extraArgs []string, hasSeed bool,
 		NetParams:         n.netParams,
 		ExtraArgs:         extraArgs,
 		FeeURL:            n.feeService.url,
+		Etcd:              n.useEtcd,
 	})
 	if err != nil {
 		return nil, err

lntest/itest/lnd_test.go

@@ -81,6 +81,9 @@ var (
 		"runtranche", defaultRunTranche, "run the tranche of the "+
 			"split test cases with the given (0-based) index",
 	)
+
+	// useEtcd test LND nodes use (embedded) etcd as remote db.
+	useEtcd = flag.Bool("etcd", false, "Use etcd backend for lnd.")
 )
 
 // getTestCaseSplitTranche returns the sub slice of the test cases that should
@@ -14250,7 +14253,9 @@ func TestLightningNetworkDaemon(t *testing.T) {
 	// Now we can set up our test harness (LND instance), with the chain
 	// backend we just created.
 	binary := ht.getLndBinary()
-	lndHarness, err = lntest.NewNetworkHarness(miner, chainBackend, binary)
+	lndHarness, err = lntest.NewNetworkHarness(
+		miner, chainBackend, binary, *useEtcd,
+	)
 	if err != nil {
 		ht.Fatalf("unable to create lightning network harness: %v", err)
 	}

lntest/node.go

@@ -183,6 +183,8 @@ type NodeConfig struct {
 	AcceptKeySend bool
 
 	FeeURL string
+
+	Etcd bool
 }
 
 func (cfg NodeConfig) P2PAddr() string {
@@ -261,6 +263,11 @@ func (cfg NodeConfig) genArgs() []string {
 		args = append(args, "--accept-keysend")
 	}
 
+	if cfg.Etcd {
+		args = append(args, "--db.backend=etcd")
+		args = append(args, "--db.etcd.embedded")
+	}
+
 	if cfg.FeeURL != "" {
 		args = append(args, "--feeurl="+cfg.FeeURL)
 	}