fix more compile errors

cmd/server/main.go

@@ -212,13 +212,15 @@ func main() {
 	go common.BlockIngestor(rpcClient, cache, log, stopChan, cacheStart)
 
 	// Compact transaction service initialization
-	service, err := frontend.NewSQLiteStreamer(rpcClient, cache, log)
-	if err != nil {
-		log.WithFields(logrus.Fields{
-			"error": err,
-		}).Fatal("couldn't create SQL backend")
+	{
+		service, err := frontend.NewLwdStreamer(cache, chainName, opts.PingEnable)
+		if err != nil {
+			common.Log.WithFields(logrus.Fields{
+				"error": err,
+			}).Fatal("couldn't create backend")
+		}
+		walletrpc.RegisterCompactTxStreamerServer(server, service)
 	}
-	defer service.(*frontend.SqlStreamer).GracefulStop()
 
 	// Register service
 	walletrpc.RegisterCompactTxStreamerServer(server, service)

common/cache.go

@@ -19,6 +19,7 @@ type BlockCache struct {
 	FirstBlock int
 	LastBlock  int
 	NextBlock  int     // height of the first block not in the cache
+	latestHash []byte  // hash of the most recent (highest height) block, for detecting reorgs.
 
 
 	m map[int]*BlockCacheEntry
@@ -123,6 +124,13 @@ func (c *BlockCache) GetLatestHeight() int {
 	return c.NextBlock - 1
 }
 
+// GetLatestHash returns the hash (block ID) of the most recent (highest) known block.
+func (c *BlockCache) GetLatestHash() []byte {
+    c.mutex.RLock()
+    defer c.mutex.RUnlock()
+    return c.latestHash
+}
+
 func (c *BlockCache) GetLatestBlock() int {
 	c.mutex.RLock()
 	defer c.mutex.RUnlock()

frontend/service.go

@@ -47,10 +47,6 @@ type SqlStreamer struct {
 	log    *logrus.Entry
 }
 
-func NewSQLiteStreamer(client *rpcclient.Client, cache *common.BlockCache, log *logrus.Entry) (walletrpc.CompactTxStreamerServer, error) {
-	return &SqlStreamer{cache, client, log}, nil
-}
-
 func (s *SqlStreamer) GracefulStop() error {
 	return nil
 }