First version with basic communication from agent to server working.

cmd/agent/agent.go

@@ -2,8 +2,8 @@ package main
 
 import (
 	"bufio"
-	"converge/cmd/comms"
 	"converge/pkg/agent"
+	"converge/pkg/comms"
 	"converge/pkg/iowrappers"
 	"converge/pkg/terminal"
 	"converge/pkg/websocketutil"

cmd/comms/agentserver.go

@@ -1,69 +0,0 @@
-package comms
-
-import (
-	"fmt"
-	"github.com/hashicorp/yamux"
-	"io"
-	"log"
-	"net"
-)
-
-type CommChannel struct {
-	Peer    net.Conn
-	Session *yamux.Session
-}
-
-type Role int
-
-const (
-	Agent Role = iota
-	ConvergeServer
-)
-
-func NewCommChannel(role Role, wsConn io.ReadWriteCloser) (CommChannel, error) {
-	var commChannel CommChannel
-	switch role {
-	case Agent:
-		listener, err := yamux.Server(wsConn, nil)
-		if err != nil {
-			return CommChannel{}, err
-		}
-		commChannel = CommChannel{
-			Peer:    nil,
-			Session: listener,
-		}
-	case ConvergeServer:
-		clientSession, err := yamux.Client(wsConn, nil)
-		if err != nil {
-			return CommChannel{}, err
-		}
-		commChannel = CommChannel{
-			Peer:    nil,
-			Session: clientSession,
-		}
-	default:
-		panic(fmt.Errorf("Undefined role %d", role))
-	}
-
-	// communication from Agent to ConvergeServer
-
-	switch role {
-	case Agent:
-		conn, err := commChannel.Session.OpenStream()
-		commChannel.Peer = conn
-		if err != nil {
-			return CommChannel{}, err
-		}
-	case ConvergeServer:
-		conn, err := commChannel.Session.Accept()
-		commChannel.Peer = conn
-		if err != nil {
-			return CommChannel{}, err
-		}
-	default:
-		panic(fmt.Errorf("Undefined role %d", role))
-	}
-
-	log.Println("Communication channel between agent and converge server established")
-	return commChannel, nil
-}

cmd/converge/server.go

@@ -51,7 +51,7 @@ func main() {
 		os.Exit(1)
 	}
 	downloadDir := *downloadOption
-	log.Println("Doanload directory", downloadDir)
+	log.Println("Download directory", downloadDir)
 
 	admin := converge.NewAdmin()
 	registrationService := websocketutil.WebSocketService{

pkg/comms/agentserver.go

@@ -0,0 +1,144 @@
+package comms
+
+import (
+	"encoding/gob"
+	"fmt"
+	"github.com/hashicorp/yamux"
+	"io"
+	"log"
+	"net"
+	"os"
+	"os/user"
+	"time"
+)
+
+type CommChannel struct {
+	Peer    net.Conn
+	Encoder *gob.Encoder
+	Decoder *gob.Decoder
+	Session *yamux.Session
+}
+
+type Role int
+
+const (
+	Agent Role = iota
+	ConvergeServer
+)
+
+func NewCommChannel(role Role, wsConn io.ReadWriteCloser) (CommChannel, error) {
+	var commChannel CommChannel
+	switch role {
+	case Agent:
+		listener, err := yamux.Server(wsConn, nil)
+		if err != nil {
+			return CommChannel{}, err
+		}
+		commChannel = CommChannel{
+			Peer:    nil,
+			Session: listener,
+		}
+	case ConvergeServer:
+		clientSession, err := yamux.Client(wsConn, nil)
+		if err != nil {
+			return CommChannel{}, err
+		}
+		commChannel = CommChannel{
+			Peer:    nil,
+			Session: clientSession,
+		}
+	default:
+		panic(fmt.Errorf("Undefined role %d", role))
+	}
+
+	// communication from Agent to ConvergeServer
+
+	switch role {
+	case Agent:
+		conn, err := commChannel.Session.OpenStream()
+		commChannel.Peer = conn
+		if err != nil {
+			return CommChannel{}, err
+		}
+	case ConvergeServer:
+		conn, err := commChannel.Session.Accept()
+		commChannel.Peer = conn
+		if err != nil {
+			return CommChannel{}, err
+		}
+	default:
+		panic(fmt.Errorf("Undefined role %d", role))
+	}
+	log.Println("Communication channel between agent and converge server established")
+
+	gob.Register(RemoteSession{})
+	gob.Register(ExpiryTimeUpdate{})
+	gob.Register(ConvergeMessage{})
+
+	commChannel.Encoder = gob.NewEncoder(commChannel.Peer)
+	commChannel.Decoder = gob.NewDecoder(commChannel.Peer)
+
+	switch role {
+	case Agent:
+		err := commChannel.Encoder.Encode(ConvergeMessage{Value: NewRemoteSession()})
+		if err != nil {
+			log.Printf("Encoding error %v", err)
+		}
+		err = commChannel.Encoder.Encode(ConvergeMessage{Value: NewExpiryTimeUpdate(time.Now())})
+		if err != nil {
+			log.Printf("Encoding error %v", err)
+		}
+	case ConvergeServer:
+		go serverReader(commChannel)
+	}
+
+	return commChannel, nil
+}
+
+func serverReader(channel CommChannel) {
+	for {
+		var result ConvergeMessage
+		err := channel.Decoder.Decode(&result)
+
+		if err != nil {
+			log.Printf("Error decoding object %v", err)
+		}
+		switch v := result.Value.(type) {
+		case RemoteSession:
+			log.Println("RECEIVED: session info ", v)
+		case ExpiryTimeUpdate:
+			log.Println("RECEIVED: expirytime update ", v)
+		default:
+			fmt.Printf("  Unknown type: %T\n", v)
+		}
+	}
+}
+
+type RemoteSession struct {
+	Username string
+	Hostname string
+	Pwd      string
+}
+
+func NewRemoteSession() RemoteSession {
+	username, _ := user.Current()
+	host, _ := os.Hostname()
+	pwd, _ := os.Getwd()
+	return RemoteSession{
+		Username: username.Username,
+		Hostname: host,
+		Pwd:      pwd,
+	}
+}
+
+type ExpiryTimeUpdate struct {
+	ExpiryTime time.Time
+}
+
+type ConvergeMessage struct {
+	Value interface{}
+}
+
+func NewExpiryTimeUpdate(expiryTime time.Time) ExpiryTimeUpdate {
+	return ExpiryTimeUpdate{ExpiryTime: expiryTime}
+}

pkg/converge/admin.go

@@ -1,7 +1,7 @@
 package converge
 
 import (
-	"converge/cmd/comms"
+	"converge/pkg/comms"
 	"converge/pkg/iowrappers"
 	"fmt"
 	"github.com/hashicorp/yamux"