change sync state logic and fix its test

syncing/interface.go

@@ -6,7 +6,6 @@ import (
 )
 
 // StateSyncInterface is the interface to do state-sync.
-// TODO(minhdoan): Nice to have, we should abstract the Blockchain type as generic type.
 type StateSyncInterface interface {
 	// Syncing blockchain from other peers.
 	// The returned channel is the signal of syncing finish.

syncing/syncing.go

@@ -59,11 +59,11 @@ func (peerConfig *SyncPeerConfig) GetBlockHashes() error {
 }
 
 // GetBlocks ...
-func (peerConfig *SyncPeerConfig) GetBlocks(heights []int32) ([][]byte, error) {
+func (peerConfig *SyncPeerConfig) GetBlocks(hashes [][]byte) ([][]byte, error) {
 	if peerConfig.client == nil {
 		return nil, ErrSyncPeerConfigClientNotReady
 	}
-	response := peerConfig.client.GetBlocks(heights)
+	response := peerConfig.client.GetBlocks(hashes)
 	return response.Payload, nil
 }
 
@@ -78,12 +78,7 @@ func (ss *StateSync) ProcessStateSyncFromPeers(peers []p2p.Peer, bc *blockchain.
 	return done, nil
 }
 
-// ProcessStateSyncFromSinglePeer used to do state sync from a single peer.
-func (ss *StateSync) ProcessStateSyncFromSinglePeer(peer *p2p.Peer, bc *blockchain.Blockchain) (chan struct{}, error) {
-	// Later.
-	return nil, nil
-}
-
+// CreateSyncConfig ...
 func (ss *StateSync) CreateSyncConfig(peers []p2p.Peer) {
 	ss.peerNumber = len(peers)
 	ss.syncConfig = &SyncConfig{
@@ -101,11 +96,11 @@ func (ss *StateSync) makeConnectionToPeers() {
 	var wg sync.WaitGroup
 	wg.Add(ss.peerNumber)
 
-	for _, synPeerConfig := range ss.syncConfig.peers {
+	for id := range ss.syncConfig.peers {
 		go func(peerConfig *SyncPeerConfig) {
 			defer wg.Done()
 			peerConfig.client = downloader.ClientSetup(peerConfig.ip, peerConfig.port)
-		}(&synPeerConfig)
+		}(&ss.syncConfig.peers[id])
 	}
 	wg.Wait()
 	ss.activePeerNumber = 0
@@ -138,14 +133,14 @@ func (ss *StateSync) getConsensusHashes() {
 		var wg sync.WaitGroup
 		wg.Add(ss.activePeerNumber)
 
-		for _, configPeer := range ss.syncConfig.peers {
-			if configPeer.client == nil {
+		for id := range ss.syncConfig.peers {
+			if ss.syncConfig.peers[id].client == nil {
 				continue
 			}
 			go func(peerConfig *SyncPeerConfig) {
 				defer wg.Done()
 				peerConfig.client.GetBlockHashes()
-			}(&configPeer)
+			}(&ss.syncConfig.peers[id])
 		}
 		wg.Wait()
 		if ss.areConsensusHashesEqual() {
@@ -173,9 +168,9 @@ func (ss *StateSync) downloadBlocks(bc *blockchain.Blockchain) {
 	// Initialize blockchain
 	bc.Blocks = make([]*blockchain.Block, ss.blockHeight)
 	var wg sync.WaitGroup
-	wg.Add(int(ss.stateSyncTaskQueue.Len()))
-	for _, configPeer := range ss.syncConfig.peers {
-		if configPeer.client == nil {
+	wg.Add(ss.activePeerNumber)
+	for i := range ss.syncConfig.peers {
+		if ss.syncConfig.peers[i].client == nil {
 			continue
 		}
 		go func(peerConfig *SyncPeerConfig, stateSyncTaskQueue *queue.Queue, bc *blockchain.Blockchain) {
@@ -188,23 +183,17 @@ func (ss *StateSync) downloadBlocks(bc *blockchain.Blockchain) {
 				syncTask := task[0].(SyncBlockTask)
 				for {
 					id := syncTask.index
-					heights := []int32{int32(id)}
-					payload, err := peerConfig.GetBlocks(heights)
+					payload, err := peerConfig.GetBlocks([][]byte{syncTask.blockHash})
 					if err == nil {
-						stop := true
-						for i, id := range heights {
-							bc.Blocks[id], err = blockchain.DeserializeBlock(payload[i])
-							if err != nil {
-								stop = false
-							}
-						}
-						if stop {
+						// As of now, only send and ask for one block.
+						bc.Blocks[id], err = blockchain.DeserializeBlock(payload[0])
+						if err == nil {
 							break
 						}
 					}
 				}
 			}
-		}(&configPeer, ss.stateSyncTaskQueue, bc)
+		}(&ss.syncConfig.peers[i], ss.stateSyncTaskQueue, bc)
 	}
 	wg.Wait()
 }

syncing/syncing_test.go

@@ -1,6 +1,7 @@
 package syncing_test
 
 import (
+	"reflect"
 	"testing"
 
 	bc "github.com/harmony-one/harmony/blockchain"
@@ -79,8 +80,9 @@ func (node *FakeNode) CalculateResponse(request *pb.DownloaderRequest) (*pb.Down
 			response.Payload = append(response.Payload, block.Hash[:])
 		}
 	} else {
-		for _, id := range request.Height {
-			response.Payload = append(response.Payload, node.bc.Blocks[id].Serialize())
+		for i := range request.Hashes {
+			block := node.bc.FindBlock(request.Hashes[i])
+			response.Payload = append(response.Payload, block.Serialize())
 		}
 	}
 	return response, nil
@@ -102,8 +104,15 @@ func TestSyncing(t *testing.T) {
 		peers[i].Ip = fakeNodes[i].ip
 		peers[i].Port = fakeNodes[i].port
 	}
+
 	stateSync.StartStateSync(peers, bc)
 
+	for i := range bc.Blocks {
+		if !reflect.DeepEqual(bc.Blocks[i], fakeNodes[0].bc.Blocks[i]) {
+			t.Error("not equal")
+		}
+	}
+
 	for _, fakeNode := range fakeNodes {
 		fakeNode.grpcServer.Stop()
 	}