add more doc

syncing/downloader/client.go

@@ -10,14 +10,14 @@ import (
 	"google.golang.org/grpc"
 )
 
-// Client ...
+// Client is the client model for downloader package.
 type Client struct {
 	dlClient pb.DownloaderClient
 	opts     []grpc.DialOption
 	conn     *grpc.ClientConn
 }
 
-// ClientSetup ...
+// ClientSetup setups a Client given ip and port.
 func ClientSetup(ip, port string) *Client {
 	client := Client{}
 	client.opts = append(client.opts, grpc.WithInsecure())
@@ -32,12 +32,12 @@ func ClientSetup(ip, port string) *Client {
 	return &client
 }
 
-// Close ...
+// Close closes the Client.
 func (client *Client) Close() {
 	client.conn.Close()
 }
 
-// GetBlockHashes ...
+// GetBlockHashes gets block hashes from all the peers by calling grpc request.
 func (client *Client) GetBlockHashes() *pb.DownloaderResponse {
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 	defer cancel()
@@ -49,7 +49,7 @@ func (client *Client) GetBlockHashes() *pb.DownloaderResponse {
 	return response
 }
 
-// GetBlocks ...
+// GetBlocks gets blocks in serialization byte array by calling a grpc request.
 func (client *Client) GetBlocks(hashes [][]byte) *pb.DownloaderResponse {
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 	defer cancel()

syncing/downloader/errors.go

@@ -2,7 +2,7 @@ package downloader
 
 import "errors"
 
-// Errors ...
+// Errors for downloader package.
 var (
 	ErrDownloaderWithNoNode = errors.New("no node attached")
 )

syncing/downloader/interface.go

@@ -4,7 +4,7 @@ import (
 	pb "github.com/harmony-one/harmony/syncing/downloader/proto"
 )
 
-// DownloadInterface ...
+// DownloadInterface is the interface for downloader package.
 type DownloadInterface interface {
 	// Syncing blockchain from other peers.
 	// The returned channel is the signal of syncing finish.

syncing/downloader/server.go

@@ -11,7 +11,7 @@ import (
 	pb "github.com/harmony-one/harmony/syncing/downloader/proto"
 )
 
-// Server ...
+// Server is the Server struct for downloader package.
 type Server struct {
 	downloadInterface DownloadInterface
 }
@@ -25,7 +25,7 @@ func (s *Server) Query(ctx context.Context, request *pb.DownloaderRequest) (*pb.
 	return response, nil
 }
 
-// Start ...
+// Start starts the Server on given ip and port.
 func (s *Server) Start(ip, port string) (*grpc.Server, error) {
 	lis, err := net.Listen("tcp", fmt.Sprintf("%s:%s", ip, port))
 	if err != nil {
@@ -38,7 +38,7 @@ func (s *Server) Start(ip, port string) (*grpc.Server, error) {
 	return grpcServer, nil
 }
 
-// NewServer ...
+// NewServer creates new Server which implements DownloadInterface.
 func NewServer(dlInterface DownloadInterface) *Server {
 	s := &Server{downloadInterface: dlInterface}
 	return s

syncing/downloader/server_test.go

@@ -52,6 +52,7 @@ func (node *FakeNode) Init() {
 	node.bc = bc.CreateBlockchainWithMoreBlocks(addresses, ShardID)
 }
 
+// CalculateResponse is the implementation for DownloadInterface.
 func (node *FakeNode) CalculateResponse(request *pb.DownloaderRequest) (*pb.DownloaderResponse, error) {
 	response := &pb.DownloaderResponse{}
 	if request.Type == pb.DownloaderRequest_HEADER {
@@ -67,6 +68,7 @@ func (node *FakeNode) CalculateResponse(request *pb.DownloaderRequest) (*pb.Down
 	return response, nil
 }
 
+// TestGetBlockHashes tests GetBlockHashes function.
 func TestGetBlockHashes(t *testing.T) {
 	fakeNode := &FakeNode{}
 	fakeNode.Init()
@@ -85,6 +87,7 @@ func TestGetBlockHashes(t *testing.T) {
 	}
 }
 
+// TestGetBlocks tests GetBlocks function.
 func TestGetBlocks(t *testing.T) {
 	fakeNode := &FakeNode{}
 	fakeNode.Init()

syncing/syncing.go

@@ -44,7 +44,7 @@ type StateSync struct {
 	stateSyncTaskQueue *queue.Queue
 }
 
-// GetBlockHashes ...
+// GetBlockHashes gets block hashes by calling grpc request to the corresponding peer.
 func (peerConfig *SyncPeerConfig) GetBlockHashes() error {
 	if peerConfig.client == nil {
 		return ErrSyncPeerConfigClientNotReady
@@ -58,7 +58,7 @@ func (peerConfig *SyncPeerConfig) GetBlockHashes() error {
 	return nil
 }
 
-// GetBlocks ...
+// GetBlocks gets blocks by calling grpc request to the corresponding peer.
 func (peerConfig *SyncPeerConfig) GetBlocks(hashes [][]byte) ([][]byte, error) {
 	if peerConfig.client == nil {
 		return nil, ErrSyncPeerConfigClientNotReady
@@ -78,7 +78,7 @@ func (ss *StateSync) ProcessStateSyncFromPeers(peers []p2p.Peer, bc *blockchain.
 	return done, nil
 }
 
-// CreateSyncConfig ...
+// CreateSyncConfig creates SyncConfig for StateSync object.
 func (ss *StateSync) CreateSyncConfig(peers []p2p.Peer) {
 	ss.peerNumber = len(peers)
 	ss.syncConfig = &SyncConfig{
@@ -92,6 +92,7 @@ func (ss *StateSync) CreateSyncConfig(peers []p2p.Peer) {
 	}
 }
 
+// makeConnectionToPeers makes grpc connection to all peers.
 func (ss *StateSync) makeConnectionToPeers() {
 	var wg sync.WaitGroup
 	wg.Add(ss.peerNumber)