Added printing state of the transfer feature

README.md

@@ -33,7 +33,7 @@ Thus, with a connection and a way of communication, the sender will send some pa
 - **VERY** expensive on resources; somewhat FIXED - [x], no more **json manipulations**, only **raw bytes**`s wizardry ! 
 - If `MAXFILEDATASIZE` is bigger than appr. 1024 - the packets on the other end will not be unmarshalled due to error ??; FIXED - [x], unnecessary, wrong, deprecated, **destroyed !!!**
 - Lack of proper error-handling; somewhat FIXED - [x]
-- Lack of information about the process of transferring (ETA, lost packets, etc.); FIXED - [ ]
+- Lack of information about the process of transferring; FIXED - [x]
 - No way to verify if the transferred file is not corrupted; FIXED via checksum- [x]
 - No encryption; FIXED via AES encryption of packets` body - [x] 
 - Messy and hard to follow code && file structure; FIXED? - [x]

protocol/constants.go

@@ -4,7 +4,7 @@ package protocol
 // MAXPACKETSIZE.
 // How many bytes can contain one packet (header + body) at maximum
 // (packets with size bigger than MAXPACKETSIZE are invalid and will not be sent)
-const MAXPACKETSIZE uint = 51200 // 50 kilobytes
+const MAXPACKETSIZE uint = 512000 // 50 kilobytes
 
 // PACKETSIZEDELIMETER.
 // Character that delimits one and the other sides of the next incoming packet.

receiver/file.go

@@ -8,7 +8,7 @@ import (
 )
 
 // Receiver`s file struct. Used internally by receiver
-type File struct {
+type file struct {
 	Filename string
 	Filesize uint64
 	CheckSum checksum.CheckSum
@@ -16,7 +16,7 @@ type File struct {
 
 // Goes through all files in the downloads directory and compares their
 // names with the name of the file that is about to be downloaded
-func (r *Receiver) CheckIfFileAlreadyExists() (bool, error) {
+func (r *Receiver) checkIfFileAlreadyExists() (bool, error) {
 	contents, err := os.ReadDir(r.DownloadsFolder)
 	if err != nil {
 		return false, fmt.Errorf("could not get contents of the downloads` directory: %s", err)

receiver/receiver.go

@@ -16,14 +16,14 @@ import (
 
 // Representation of a receiver
 type Receiver struct {
-	DownloadsFolder        string
-	Connection             net.Conn
-	IncomingPackets        chan protocol.Packet
-	FileToDownload         *File
-	EncryptionKey          []byte
-	ReadyToReceive         bool
-	Stopped                bool
-	FileBytesPacketCounter uint64
+	DownloadsFolder string
+	Connection      net.Conn
+	IncomingPackets chan protocol.Packet
+	FileToDownload  *file
+	EncryptionKey   []byte
+	ReadyToReceive  bool
+	Stopped         bool
+	TransferInfo    *transferInfo
 }
 
 // Creates a new client with default fields
@@ -40,7 +40,6 @@ func NewReceiver(downloadsFolder string) *Receiver {
 
 	incomingPacketsChan := make(chan protocol.Packet, 5000)
 
-	var PacketCounter uint64 = 0
 	fmt.Println("Created a new receiver")
 	return &Receiver{
 		DownloadsFolder: downloadsFolder,
@@ -48,11 +47,14 @@ func NewReceiver(downloadsFolder string) *Receiver {
 		IncomingPackets: incomingPacketsChan,
 		Stopped:         false,
 		ReadyToReceive:  false,
-		FileToDownload: &File{
+		FileToDownload: &file{
 			Filename: "",
 			Filesize: 0,
 		},
-		FileBytesPacketCounter: PacketCounter,
+		TransferInfo: &transferInfo{
+			ReceivedFileBytesPackets:       0,
+			ApproximateNumberOfFilePackets: 0,
+		},
 	}
 }
 
@@ -88,7 +90,6 @@ func (r *Receiver) Connect(addr string) error {
 // Handles the input from the user after the sender sent "DOYOUACCEPT?" packet.
 // The choice of acceptance is given to the user
 func (r *Receiver) HandleFileOffer() error {
-
 	// inform the user about the file
 
 	fmt.Printf(`
@@ -122,7 +123,7 @@ func (r *Receiver) HandleFileOffer() error {
 	// accept the file
 
 	// check if the file with the same name is present
-	doesExist, err := r.CheckIfFileAlreadyExists()
+	doesExist, err := r.checkIfFileAlreadyExists()
 	if err != nil {
 		return fmt.Errorf("could not check if the file with the same name alredy exists: %s", err)
 	}
@@ -154,6 +155,8 @@ func (r *Receiver) HandleFileOffer() error {
 		return fmt.Errorf("could not send an acceptance packet: %s", err)
 	}
 
+	r.TransferInfo.ApproximateNumberOfFilePackets = uint64(float32(r.FileToDownload.Filesize) / float32(protocol.MAXPACKETSIZE))
+
 	return nil
 }
 
@@ -171,11 +174,38 @@ func (r *Receiver) WritePieceOfFile(filePacket protocol.Packet) error {
 	// just write the bytes
 	file.Write(filePacket.Body)
 	file.Close()
-	r.FileBytesPacketCounter++
+	r.TransferInfo.ReceivedFileBytesPackets++
 
 	return nil
 }
 
+// Prints a brief information about the state of the transfer
+func (r *Receiver) PrintTransferInfo(pauseDuration time.Duration) {
+	next := time.Now().UTC()
+	for {
+		if r.TransferInfo.ReceivedFileBytesPackets == 0 {
+			time.Sleep(time.Second)
+			continue
+		}
+
+		now := time.Now().UTC()
+
+		if !now.After(next) {
+			continue
+		}
+		next = now.Add(pauseDuration)
+
+		fmt.Printf(`
+ | Received packets/Approximate number of packets
+ | (%d|%d) (%.2f%%/100%%)
+`, r.TransferInfo.ReceivedFileBytesPackets,
+			r.TransferInfo.ApproximateNumberOfFilePackets,
+			float32(r.TransferInfo.ReceivedFileBytesPackets)/float32(r.TransferInfo.ApproximateNumberOfFilePackets)*100)
+
+		time.Sleep(pauseDuration)
+	}
+}
+
 // Listens in an endless loop; reads incoming packets, decrypts their BODY and puts into channel
 func (r *Receiver) ReceivePackets() {
 	for {
@@ -212,8 +242,7 @@ func (r *Receiver) ReceivePackets() {
 // in any order and react correspondingly
 func (r *Receiver) MainLoop() {
 	go r.ReceivePackets()
-
-	// r.Stop()
+	go r.PrintTransferInfo(time.Second * 3)
 
 	for {
 		if r.Stopped {
@@ -291,8 +320,8 @@ func (r *Receiver) MainLoop() {
 			// the sender has completed its mission,
 			// checking hashes and exiting
 
-			fmt.Println("Got ", r.FileBytesPacketCounter, " file packets in total")
-			fmt.Println("Checking checksums...")
+			fmt.Println("Got ", r.TransferInfo.ReceivedFileBytesPackets, " file packets in total")
+			fmt.Println("Comparing checksums...")
 
 			file, err := os.Open(filepath.Join(r.DownloadsFolder, r.FileToDownload.Filename))
 			if err != nil {

receiver/transferinfo.go

@@ -0,0 +1,6 @@
+package receiver
+
+type transferInfo struct {
+	ReceivedFileBytesPackets       uint64
+	ApproximateNumberOfFilePackets uint64
+}

sender/file.go

@@ -8,7 +8,7 @@ import (
 )
 
 // Struct that represents the served file. Used internally in the sender
-type File struct {
+type file struct {
 	path      string
 	Filename  string
 	Filesize  uint64
@@ -19,7 +19,7 @@ type File struct {
 }
 
 // Prepares a file for serving. Used for preparing info before sending a fileinfo packet by sender
-func getFile(path string) (*File, error) {
+func getFile(path string) (*file, error) {
 	info, err := os.Stat(path)
 	if err != nil {
 		return nil, fmt.Errorf("could not get a fileinfo: %s", err)
@@ -33,7 +33,7 @@ func getFile(path string) (*File, error) {
 		return nil, fmt.Errorf("could not get a partial file checksum: %s", err)
 	}
 
-	return &File{
+	return &file{
 		path:      path,
 		Filename:  info.Name(),
 		Filesize:  uint64(info.Size()),

sender/sender.go

@@ -5,6 +5,7 @@ import (
 	"net"
 	"os"
 	"strconv"
+	"time"
 
 	"github.com/Unbewohnte/FTU/checksum"
 	"github.com/Unbewohnte/FTU/encryption"
@@ -13,16 +14,16 @@ import (
 
 // The main sender struct
 type Sender struct {
-	Port                 int
-	FileToTransfer       *File
-	Listener             net.Listener
-	Connection           net.Conn
-	IncomingPackets      chan protocol.Packet
-	EncryptionKey        []byte
-	SentFileBytesPackets uint64
-	TransferAllowed      bool
-	ReceiverIsReady      bool
-	Stopped              bool
+	Port            int
+	FileToTransfer  *file
+	Listener        net.Listener
+	Connection      net.Conn
+	IncomingPackets chan protocol.Packet
+	EncryptionKey   []byte
+	TransferInfo    *transferInfo
+	TransferAllowed bool
+	ReceiverIsReady bool
+	Stopped         bool
 }
 
 // Creates a new sender with default|necessary fields
@@ -49,21 +50,23 @@ func NewSender(port int, filepath string) *Sender {
 
 	// !!!
 	key := encryption.Generate32AESkey()
-	fmt.Printf("GENERATED ENCRYPTION KEY: %s\n", key)
+	fmt.Printf("Generated an encryption key: %s\n", key)
 
-	var filepacketCounter uint64
 	fmt.Printf("Created a new sender at %s:%d (remote)\n%s:%d (local)\n", remoteIP, port, localIP, port)
 	return &Sender{
-		Port:                 port,
-		FileToTransfer:       fileToTransfer,
-		Listener:             listener,
-		Connection:           nil,
-		IncomingPackets:      incomingPacketsChan,
-		SentFileBytesPackets: filepacketCounter,
-		EncryptionKey:        key,
-		TransferAllowed:      false,
-		ReceiverIsReady:      false,
-		Stopped:              false,
+		Port:            port,
+		FileToTransfer:  fileToTransfer,
+		Listener:        listener,
+		Connection:      nil,
+		IncomingPackets: incomingPacketsChan,
+		TransferInfo: &transferInfo{
+			SentFileBytesPackets:           0,
+			ApproximateNumberOfFilePackets: uint64(float32(fileToTransfer.Filesize) / float32(protocol.MAXPACKETSIZE)),
+		},
+		EncryptionKey:   key,
+		TransferAllowed: false,
+		ReceiverIsReady: false,
+		Stopped:         false,
 	}
 }
 
@@ -166,7 +169,7 @@ func (s *Sender) SendOffer() error {
 func (s *Sender) SendPiece() error {
 	// if no data to send - exit
 	if s.FileToTransfer.LeftBytes == 0 {
-		fmt.Printf("Done. Sent %d file packets\n", s.SentFileBytesPackets)
+		fmt.Printf("Done. Sent %d file packets\n", s.TransferInfo.SentFileBytesPackets)
 		s.Stop()
 	}
 
@@ -198,14 +201,41 @@ func (s *Sender) SendPiece() error {
 		return fmt.Errorf("could not send a file packet : %s", err)
 	}
 
-	// doing a "logging" for the next time
+	// doing a "logging" for the next piece
 	s.FileToTransfer.LeftBytes -= uint64(read)
 	s.FileToTransfer.SentBytes += uint64(read)
-	s.SentFileBytesPackets++
+	s.TransferInfo.SentFileBytesPackets++
 
 	return nil
 }
 
+// Prints a brief information about the state of the transfer
+func (s *Sender) PrintTransferInfo(pauseDuration time.Duration) {
+	next := time.Now().UTC()
+	for {
+		if !s.TransferAllowed {
+			time.Sleep(time.Second)
+			continue
+		}
+
+		now := time.Now().UTC()
+
+		if !now.After(next) {
+			continue
+		}
+		next = now.Add(pauseDuration)
+
+		fmt.Printf(`
+ | Sent packets/Approximate number of packets
+ | (%d|%d) (%.2f%%/100%%)
+`, s.TransferInfo.SentFileBytesPackets,
+			s.TransferInfo.ApproximateNumberOfFilePackets,
+			float32(s.TransferInfo.SentFileBytesPackets)/float32(s.TransferInfo.ApproximateNumberOfFilePackets)*100)
+
+		time.Sleep(pauseDuration)
+	}
+}
+
 // Listens in an endless loop; reads incoming packets, decrypts their BODY and puts into channel
 func (s *Sender) ReceivePackets() {
 	for {
@@ -237,6 +267,7 @@ func (s *Sender) ReceivePackets() {
 func (s *Sender) MainLoop() {
 
 	go s.ReceivePackets()
+	go s.PrintTransferInfo(time.Second * 3)
 
 	// instantly sending an encryption key, following the protocol`s rule
 	err := s.SendEncryptionKey()

sender/transferinfo.go

@@ -0,0 +1,6 @@
+package sender
+
+type transferInfo struct {
+	SentFileBytesPackets           uint64
+	ApproximateNumberOfFilePackets uint64
+}