core: hide types.NodeID from full node. (#147)

* Refine core.Governance interface
- Remove types.NodeID from interface declaration.
- All parameter should be round based.
* Add core.NodeSetCache
* Agreement accepts map of nodeID directly.
* test.Transport.Peers method return public keys.

1 files changed, 72 insertions, 29 deletions

diff --git a/core/test/tcp-transport.go b/core/test/tcp-transport.go
index 0f9bd73..6e3ddfb 100644
--- a/core/test/tcp-transport.go
+++ b/core/test/tcp-transport.go
@@ -19,6 +19,7 @@ package test
 
 import (
 	"context"
+	"encoding/base64"
 	"encoding/binary"
 	"encoding/json"
 	"fmt"
@@ -28,13 +29,22 @@ import (
 	"net"
 	"os"
 	"strconv"
+	"strings"
 	"sync"
 	"syscall"
 	"time"
 
+	"github.com/dexon-foundation/dexon-consensus-core/core/crypto"
+	"github.com/dexon-foundation/dexon-consensus-core/core/crypto/ecdsa"
 	"github.com/dexon-foundation/dexon-consensus-core/core/types"
 )
 
+type tcpPeerRecord struct {
+	conn        string
+	sendChannel chan<- []byte
+	pubKey      crypto.PublicKey
+}
+
 // tcpMessage is the general message between peers and server.
 type tcpMessage struct {
 	NodeID types.NodeID `json:"nid"`
@@ -42,13 +52,33 @@ type tcpMessage struct {
 	Info   string       `json:"conn"`
 }
 
+// buildPeerInfo is a tricky way to combine connection string and
+// base64 encoded byte slice for public key into a single string,
+// separated by ';'.
+func buildPeerInfo(pubKey crypto.PublicKey, conn string) string {
+	return conn + ";" + base64.StdEncoding.EncodeToString(pubKey.Bytes())
+}
+
+// parsePeerInfo parse connection string and base64 encoded public key built
+// via buildPeerInfo.
+func parsePeerInfo(info string) (key crypto.PublicKey, conn string) {
+	tokens := strings.Split(info, ";")
+	conn = tokens[0]
+	data, err := base64.StdEncoding.DecodeString(tokens[1])
+	if err != nil {
+		panic(err)
+	}
+	key = ecdsa.NewPublicKeyFromByteSlice(data)
+	return
+}
+
 // TCPTransport implements Transport interface via TCP connection.
 type TCPTransport struct {
 	peerType    TransportPeerType
 	nID         types.NodeID
+	pubKey      crypto.PublicKey
 	localPort   int
-	peersInfo   map[types.NodeID]string
-	peers       map[types.NodeID]chan<- []byte
+	peers       map[types.NodeID]*tcpPeerRecord
 	peersLock   sync.RWMutex
 	recvChannel chan *TransportEnvelope
 	ctx         context.Context
@@ -60,7 +90,7 @@ type TCPTransport struct {
 // NewTCPTransport constructs an TCPTransport instance.
 func NewTCPTransport(
 	peerType TransportPeerType,
-	nID types.NodeID,
+	pubKey crypto.PublicKey,
 	latency LatencyModel,
 	marshaller Marshaller,
 	localPort int) *TCPTransport {
@@ -68,9 +98,9 @@ func NewTCPTransport(
 	ctx, cancel := context.WithCancel(context.Background())
 	return &TCPTransport{
 		peerType:    peerType,
-		nID:         nID,
-		peersInfo:   make(map[types.NodeID]string),
-		peers:       make(map[types.NodeID]chan<- []byte),
+		nID:         types.NewNodeID(pubKey),
+		pubKey:      pubKey,
+		peers:       make(map[types.NodeID]*tcpPeerRecord),
 		recvChannel: make(chan *TransportEnvelope, 1000),
 		ctx:         ctx,
 		cancel:      cancel,
@@ -96,7 +126,7 @@ func (t *TCPTransport) Send(
 		t.peersLock.RLock()
 		defer t.peersLock.RUnlock()
 
-		t.peers[endpoint] <- payload
+		t.peers[endpoint].sendChannel <- payload
 	}()
 	return
 }
@@ -110,7 +140,7 @@ func (t *TCPTransport) Broadcast(msg interface{}) (err error) {
 	t.peersLock.RLock()
 	defer t.peersLock.RUnlock()
 
-	for nID, ch := range t.peers {
+	for nID, rec := range t.peers {
 		if nID == t.nID {
 			continue
 		}
@@ -119,7 +149,7 @@ func (t *TCPTransport) Broadcast(msg interface{}) (err error) {
 				time.Sleep(t.latency.Delay())
 			}
 			ch <- payload
-		}(ch)
+		}(rec.sendChannel)
 	}
 	return
 }
@@ -131,7 +161,7 @@ func (t *TCPTransport) Close() (err error) {
 	// Reset peers.
 	t.peersLock.Lock()
 	defer t.peersLock.Unlock()
-	t.peers = make(map[types.NodeID]chan<- []byte)
+	t.peers = make(map[types.NodeID]*tcpPeerRecord)
 	// Tell our user that this channel is closed.
 	close(t.recvChannel)
 	t.recvChannel = nil
@@ -139,10 +169,9 @@ func (t *TCPTransport) Close() (err error) {
 }
 
 // Peers implements Transport.Peers method.
-func (t *TCPTransport) Peers() (peers map[types.NodeID]struct{}) {
-	peers = make(map[types.NodeID]struct{})
-	for nID := range t.peersInfo {
-		peers[nID] = struct{}{}
+func (t *TCPTransport) Peers() (peers []crypto.PublicKey) {
+	for _, rec := range t.peers {
+		peers = append(peers, rec.pubKey)
 	}
 	return
 }
@@ -376,7 +405,7 @@ func (t *TCPTransport) listenerRoutine(listener *net.TCPListener) {
 // we only utilize the write part for simplicity.
 func (t *TCPTransport) buildConnectionsToPeers() (err error) {
 	var wg sync.WaitGroup
-	for nID, addr := range t.peersInfo {
+	for nID, rec := range t.peers {
 		if nID == t.nID {
 			continue
 		}
@@ -394,8 +423,8 @@ func (t *TCPTransport) buildConnectionsToPeers() (err error) {
 			t.peersLock.Lock()
 			defer t.peersLock.Unlock()
 
-			t.peers[nID] = t.connWriter(conn)
-		}(nID, addr)
+			t.peers[nID].sendChannel = t.connWriter(conn)
+		}(nID, rec.conn)
 	}
 	wg.Wait()
 	return
@@ -410,14 +439,15 @@ type TCPTransportClient struct {
 
 // NewTCPTransportClient constructs a TCPTransportClient instance.
 func NewTCPTransportClient(
-	nID types.NodeID,
+	pubKey crypto.PublicKey,
 	latency LatencyModel,
 	marshaller Marshaller,
 	local bool) *TCPTransportClient {
 
 	return &TCPTransportClient{
-		TCPTransport: *NewTCPTransport(TransportPeer, nID, latency, marshaller, 8080),
-		local:        local,
+		TCPTransport: *NewTCPTransport(
+			TransportPeer, pubKey, latency, marshaller, 8080),
+		local: local,
 	}
 }
 
@@ -436,7 +466,6 @@ func (t *TCPTransportClient) Report(msg interface{}) (err error) {
 // Join implements TransportClient.Join method.
 func (t *TCPTransportClient) Join(
 	serverEndpoint interface{}) (ch <-chan *TransportEnvelope, err error) {
-
 	// Initiate a TCP server.
 	// TODO(mission): config initial listening port.
 	var (
@@ -475,7 +504,6 @@ func (t *TCPTransportClient) Join(
 		t.localPort = 1024 + rand.Int()%1024
 	}
 	go t.listenerRoutine(ln.(*net.TCPListener))
-
 	serverConn, err := net.Dial("tcp", serverEndpoint.(string))
 	if err != nil {
 		return
@@ -492,17 +520,26 @@ func (t *TCPTransportClient) Join(
 		conn = net.JoinHostPort(ip, strconv.Itoa(t.localPort))
 	}
 	if err = t.Report(&tcpMessage{
-		Type:   "conn",
 		NodeID: t.nID,
-		Info:   conn,
+		Type:   "conn",
+		Info:   buildPeerInfo(t.pubKey, conn),
 	}); err != nil {
 		return
 	}
 	// Wait for peers list sent by server.
 	e := <-t.recvChannel
-	if t.peersInfo, ok = e.Msg.(map[types.NodeID]string); !ok {
+	peersInfo, ok := e.Msg.(map[types.NodeID]string)
+	if !ok {
 		panic(fmt.Errorf("expect peer list, not %v", e))
 	}
+	// Setup peers information.
+	for nID, info := range peersInfo {
+		pubKey, conn := parsePeerInfo(info)
+		t.peers[nID] = &tcpPeerRecord{
+			conn:   conn,
+			pubKey: pubKey,
+		}
+	}
 	// Setup connections to other peers.
 	if err = t.buildConnectionsToPeers(); err != nil {
 		return
@@ -551,7 +588,7 @@ func NewTCPTransportServer(
 		//       won't be zero.
 		TCPTransport: *NewTCPTransport(
 			TransportPeerServer,
-			types.NodeID{},
+			ecdsa.NewPublicKeyFromByteSlice(nil),
 			nil,
 			marshaller,
 			serverPort),
@@ -576,6 +613,7 @@ func (t *TCPTransportServer) Host() (chan *TransportEnvelope, error) {
 func (t *TCPTransportServer) WaitForPeers(numPeers int) (err error) {
 	// Collect peers info. Packets other than peer info is
 	// unexpected.
+	peersInfo := make(map[types.NodeID]string)
 	for {
 		// Wait for connection info reported by peers.
 		e := <-t.recvChannel
@@ -586,9 +624,14 @@ func (t *TCPTransportServer) WaitForPeers(numPeers int) (err error) {
 		if msg.Type != "conn" {
 			panic(fmt.Errorf("expect connection report, not %v", e))
 		}
-		t.peersInfo[msg.NodeID] = msg.Info
+		pubKey, conn := parsePeerInfo(msg.Info)
+		t.peers[msg.NodeID] = &tcpPeerRecord{
+			conn:   conn,
+			pubKey: pubKey,
+		}
+		peersInfo[msg.NodeID] = msg.Info
 		// Check if we already collect enought peers.
-		if len(t.peersInfo) == numPeers {
+		if len(peersInfo) == numPeers {
 			break
 		}
 	}
@@ -596,7 +639,7 @@ func (t *TCPTransportServer) WaitForPeers(numPeers int) (err error) {
 	if err = t.buildConnectionsToPeers(); err != nil {
 		return
 	}
-	if err = t.Broadcast(t.peersInfo); err != nil {
+	if err = t.Broadcast(peersInfo); err != nil {
 		return
 	}
 	// Wait for peers to send 'ready' report.