chainntnfs: add height hint caches to chain notifiers

chainntnfs/btcdnotify/btcd.go

@@ -83,6 +83,16 @@ type BtcdNotifier struct {
 	chainUpdates *chainntnfs.ConcurrentQueue
 	txUpdates    *chainntnfs.ConcurrentQueue
 
+	// spendHintCache is a cache used to query and update the latest height
+	// hints for an outpoint. Each height hint represents the earliest
+	// height at which the outpoint could have been spent within the chain.
+	spendHintCache chainntnfs.SpendHintCache
+
+	// confirmHintCache is a cache used to query the latest height hints for
+	// a transaction. Each height hint represents the earliest height at
+	// which the transaction could have confirmed within the chain.
+	confirmHintCache chainntnfs.ConfirmHintCache
+
 	wg   sync.WaitGroup
 	quit chan struct{}
 }
@@ -93,7 +103,9 @@ var _ chainntnfs.ChainNotifier = (*BtcdNotifier)(nil)
 // New returns a new BtcdNotifier instance. This function assumes the btcd node
 // detailed in the passed configuration is already running, and willing to
 // accept new websockets clients.
-func New(config *rpcclient.ConnConfig) (*BtcdNotifier, error) {
+func New(config *rpcclient.ConnConfig, spendHintCache chainntnfs.SpendHintCache,
+	confirmHintCache chainntnfs.ConfirmHintCache) (*BtcdNotifier, error) {
+
 	notifier := &BtcdNotifier{
 		notificationCancels:  make(chan interface{}),
 		notificationRegistry: make(chan interface{}),
@@ -105,6 +117,9 @@ func New(config *rpcclient.ConnConfig) (*BtcdNotifier, error) {
 		chainUpdates: chainntnfs.NewConcurrentQueue(10),
 		txUpdates:    chainntnfs.NewConcurrentQueue(10),
 
+		spendHintCache:   spendHintCache,
+		confirmHintCache: confirmHintCache,
+
 		quit: make(chan struct{}),
 	}
 
@@ -150,7 +165,8 @@ func (b *BtcdNotifier) Start() error {
 	}
 
 	b.txConfNotifier = chainntnfs.NewTxConfNotifier(
-		uint32(currentHeight), reorgSafetyLimit)
+		uint32(currentHeight), reorgSafetyLimit, b.confirmHintCache,
+	)
 
 	b.bestBlock = chainntnfs.BlockEpoch{
 		Height: currentHeight,