Rework network protocol & other fixes

.gitignore

@@ -0,0 +1 @@
+main

README.md

@@ -13,8 +13,8 @@ import (
 	"log"
 	"os"
 
-	"github.com/o3labs/neo-transaction-watcher/neotx"
-	"github.com/o3labs/neo-transaction-watcher/neotx/network"
+	"github.com/corollari/neo-transaction-watcher/neotx"
+	"github.com/corollari/neo-transaction-watcher/neotx/network"
 )
 
 type Handler struct {

main.go

@@ -4,8 +4,8 @@ import (
 	"log"
 	"os"
 
-	"github.com/o3labs/neo-transaction-watcher/neotx"
-	"github.com/o3labs/neo-transaction-watcher/neotx/network"
+	"github.com/corollari/neo-transaction-watcher/neotx"
+	"github.com/corollari/neo-transaction-watcher/neotx/network"
 )
 
 type Handler struct {
@@ -28,7 +28,7 @@ func main() {
 	config := neotx.Config{
 		Network:   neotx.NEOMainNet,
 		Port:      10333,
-		IPAddress: "52.193.202.2",
+		IPAddress: "207.180.217.134",
 	}
 	client := neotx.NewClient(config)
 	handler := &Handler{}

neotx/network.go

@@ -7,8 +7,9 @@ import (
 	"io"
 	"log"
 	"net"
+	"time"
 
-	"github.com/o3labs/neo-transaction-watcher/neotx/network"
+	"github.com/corollari/neo-transaction-watcher/neotx/network"
 )
 
 //Network
@@ -51,6 +52,17 @@ type Interface interface {
 	SetDelegate(MessageDelegate)
 }
 
+func startPingLoop(c *Client) {
+	conn := c.connection
+	for {
+		time.Sleep(1000 * time.Millisecond)
+		nonce, _ := network.RandomUint32()
+		payload := network.NewPingPayload(nonce)
+		pingCommand := network.NewMessage(c.Config.Network, network.CommandPing, payload)
+		conn.Write(pingCommand)
+	}
+}
+
 var _ Interface = (*Client)(nil)
 
 func (c *Client) handleConnection() {
@@ -73,17 +85,18 @@ func (c *Client) handleConnection() {
 			return
 		}
 
+		payloadByte := make([]byte, msg.Length)
+		_, err = io.ReadFull(conn, payloadByte)
+		if err != nil {
+			if c.delegate != nil {
+				go c.delegate.OnError(err)
+			}
+			continue
+		}
+
 		//receive version from remote node
 		if msg.Command == string(network.CommandVersion) {
 			out := &network.Version{}
-			payloadByte := make([]byte, msg.Length)
-			_, err = io.ReadFull(conn, payloadByte)
-			if err != nil {
-				if c.delegate != nil {
-					go c.delegate.OnError(err)
-				}
-				continue
-			}
 			pr := bytes.NewBuffer(payloadByte)
 			out.Decode(pr, 0)
 			//reply with verack
@@ -94,29 +107,15 @@ func (c *Client) handleConnection() {
 				go c.delegate.OnConnected(*out)
 			}
 		} else if msg.Command == string(network.CommandVerack) {
-
+			go startPingLoop(c)
+		} else if msg.Command == string(network.CommandPong) {
+			log.Println("Pong!")
 		} else if msg.Command == string(network.CommandAddr) {
 			out := &network.Addr{}
-			payloadByte := make([]byte, msg.Length)
-			_, err = io.ReadFull(conn, payloadByte)
-			if err != nil {
-				if c.delegate != nil {
-					go c.delegate.OnError(err)
-				}
-				continue
-			}
 			pr := bytes.NewBuffer(payloadByte)
 			out.Decode(pr, 0)
 		} else if msg.Command == string(network.CommandInv) {
 			out := &network.Inv{}
-			payloadByte := make([]byte, msg.Length)
-			_, err = io.ReadFull(conn, payloadByte)
-			if err != nil {
-				if c.delegate != nil {
-					go c.delegate.OnError(err)
-				}
-				continue
-			}
 			log.Printf("msg = %+v\n", msg)
 			pr := bytes.NewBuffer(payloadByte)
 			out.Decode(pr, 0)
@@ -132,7 +131,8 @@ func (c *Client) handleConnection() {
 					go c.delegate.OnReceive(tx)
 				}
 			}
-
+		} else {
+			log.Printf("Unhandled message: %s\n", msg.Command)
 		}
 	}
 }

neotx/network/ping.go

@@ -0,0 +1,58 @@
+package network
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"time"
+)
+
+type Ping struct {
+	Timestamp   uint32      //4 bytes
+	Nonce       uint32      //4 bytes
+	BlockHeight uint32      //4 bytes
+}
+
+func NewPingPayload(nonce uint32) *Ping {
+
+	v := Ping{}
+	v.Timestamp = uint32(time.Unix(time.Now().Unix(), 0).Unix())
+	v.Nonce = nonce
+	v.BlockHeight = 0 //TODO get this from a chain data
+	return &v
+}
+
+func (v *Ping) Decode(r io.Reader, protocolVersion uint32) error {
+
+	buf, ok := r.(*bytes.Buffer)
+
+	if !ok {
+		return fmt.Errorf("Ping decode reader is not a *byte.Buffer")
+	}
+
+	err := ReadElements(buf, &v.BlockHeight, (*uint32)(&v.Timestamp), &v.Nonce)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (v *Ping) Encode(w io.Writer, protocolVersion uint32) error {
+	err := WriteElement(w, v.BlockHeight)
+	if err != nil {
+		return err
+	}
+
+	err = WriteElement(w, v.Timestamp)
+	if err != nil {
+		return err
+	}
+
+	err = WriteElement(w, v.Nonce)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

neotx/network/version.go

@@ -11,7 +11,7 @@ type ServiceFlag uint64
 
 const (
 	MaxUserAgentLength = 1024
-	DefaultUserAgent   = "NEOxO3:0.0.1;" //test
+	DefaultUserAgent   = "/Neo:2.10.2/" //test
 	ProtocolVersion    = uint32(0)
 	DefaultServiceFlag = ServiceFlag(1)
 )