Streaming Transfers (#153)

internal/cron/cron.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	"emperror.dev/errors"
-	log2 "github.com/apex/log"
+	"github.com/apex/log"
 	"github.com/go-co-op/gocron"
 
 	"github.com/pterodactyl/wings/config"
@@ -24,7 +24,7 @@ func Scheduler(ctx context.Context, m *server.Manager) (*gocron.Scheduler, error
 	if !o.SwapIf(true) {
 		return nil, errors.New("cron: cannot call scheduler more than once in application lifecycle")
 	}
-	l, err := time.LoadLocation(config.Get().System.Timezone)
+	location, err := time.LoadLocation(config.Get().System.Timezone)
 	if err != nil {
 		return nil, errors.Wrap(err, "cron: failed to parse configured system timezone")
 	}
@@ -41,30 +41,30 @@ func Scheduler(ctx context.Context, m *server.Manager) (*gocron.Scheduler, error
 		max:     config.Get().System.ActivitySendCount,
 	}
 
-	s := gocron.NewScheduler(l)
+	s := gocron.NewScheduler(location)
-	log := log2.WithField("subsystem", "cron")
+	l := log.WithField("subsystem", "cron")
 
 	interval := time.Duration(config.Get().System.ActivitySendInterval) * time.Second
-	log.WithField("interval", interval).Info("configuring system crons")
+	l.WithField("interval", interval).Info("configuring system crons")
 
 	_, _ = s.Tag("activity").Every(interval).Do(func() {
-		log.WithField("cron", "activity").Debug("sending internal activity events to Panel")
+		l.WithField("cron", "activity").Debug("sending internal activity events to Panel")
 		if err := activity.Run(ctx); err != nil {
 			if errors.Is(err, ErrCronRunning) {
-				log.WithField("cron", "activity").Warn("activity process is already running, skipping...")
+				l.WithField("cron", "activity").Warn("activity process is already running, skipping...")
 			} else {
-				log.WithField("cron", "activity").WithField("error", err).Error("activity process failed to execute")
+				l.WithField("cron", "activity").WithField("error", err).Error("activity process failed to execute")
 			}
 		}
 	})
 
 	_, _ = s.Tag("sftp").Every(interval).Do(func() {
-		log.WithField("cron", "sftp").Debug("sending sftp events to Panel")
+		l.WithField("cron", "sftp").Debug("sending sftp events to Panel")
 		if err := sftp.Run(ctx); err != nil {
 			if errors.Is(err, ErrCronRunning) {
-				log.WithField("cron", "sftp").Warn("sftp events process already running, skipping...")
+				l.WithField("cron", "sftp").Warn("sftp events process already running, skipping...")
 			} else {
-				log.WithField("cron", "sftp").WithField("error", err).Error("sftp events process failed to execute")
+				l.WithField("cron", "sftp").WithField("error", err).Error("sftp events process failed to execute")
 			}
 		}
 	})

internal/progress/progress.go

@@ -0,0 +1,90 @@
+package progress
+
+import (
+	"io"
+	"strings"
+	"sync/atomic"
+
+	"github.com/pterodactyl/wings/system"
+)
+
+// Progress is used to track the progress of any I/O operation that are being
+// performed.
+type Progress struct {
+	// written is the total size of the files that have been written to the writer.
+	written uint64
+	// Total is the total size of the archive in bytes.
+	total uint64
+
+	// Writer .
+	Writer io.Writer
+}
+
+// NewProgress returns a new progress tracker for the given total size.
+func NewProgress(total uint64) *Progress {
+	return &Progress{total: total}
+}
+
+// Written returns the total number of bytes written.
+// This function should be used when the progress is tracking data being written.
+func (p *Progress) Written() uint64 {
+	return atomic.LoadUint64(&p.written)
+}
+
+// Total returns the total size in bytes.
+func (p *Progress) Total() uint64 {
+	return atomic.LoadUint64(&p.total)
+}
+
+// SetTotal sets the total size of the archive in bytes. This function is safe
+// to call concurrently and can be used to update the total size if it changes,
+// such as when the total size is simultaneously being calculated as data is
+// being written through the progress writer.
+func (p *Progress) SetTotal(total uint64) {
+	atomic.StoreUint64(&p.total, total)
+}
+
+// Write totals the number of bytes that have been written to the writer.
+func (p *Progress) Write(v []byte) (int, error) {
+	n := len(v)
+	atomic.AddUint64(&p.written, uint64(n))
+	if p.Writer != nil {
+		return p.Writer.Write(v)
+	}
+	return n, nil
+}
+
+// Progress returns a formatted progress string for the current progress.
+func (p *Progress) Progress(width int) string {
+	// current = 100 (Progress, dynamic)
+	// total = 1000 (Content-Length, dynamic)
+	// width = 25 (Number of ticks to display, static)
+	// widthPercentage = 100 / width (What percentage does each tick represent, static)
+	//
+	// percentageDecimal = current / total = 0.1
+	// percentage = percentageDecimal * 100 = 10%
+	// ticks = percentage / widthPercentage = 2.5
+	//
+	// ticks is a float64, so we cast it to an int which rounds it down to 2.
+
+	// Values are cast to floats to prevent integer division.
+	current := p.Written()
+	total := p.Total()
+	// width := is passed as a parameter
+	widthPercentage := float64(100) / float64(width)
+	percentageDecimal := float64(current) / float64(total)
+	percentage := percentageDecimal * 100
+	ticks := int(percentage / widthPercentage)
+
+	// Ensure that we never get a negative number of ticks, this will prevent strings#Repeat
+	// from panicking.  A negative number of ticks is likely to happen when the total size is
+	// inaccurate, such as when we are going off of rough disk usage calculation.
+	if ticks < 0 {
+		ticks = 0
+	} else if ticks > width {
+		ticks = width
+	}
+
+	bar := strings.Repeat("=", ticks) + strings.Repeat(" ", width-ticks)
+	return "[" + bar + "] " + system.FormatBytes(current) + " / " + system.FormatBytes(total)
+}

internal/progress/progress_test.go

@@ -1,47 +1,49 @@
-package filesystem
+package progress_test
 
 import (
 	"bytes"
 	"testing"
 
-	. "github.com/franela/goblin"
+	"github.com/franela/goblin"
+
+	"github.com/pterodactyl/wings/internal/progress"
 )
 
 func TestProgress(t *testing.T) {
-	g := Goblin(t)
+	g := goblin.Goblin(t)
 
 	g.Describe("Progress", func() {
 		g.It("properly initializes", func() {
-			total := int64(1000)
+			total := uint64(1000)
-			p := NewProgress(total)
+			p := progress.NewProgress(total)
 			g.Assert(p).IsNotNil()
 			g.Assert(p.Total()).Equal(total)
-			g.Assert(p.Written()).Equal(int64(0))
+			g.Assert(p.Written()).Equal(uint64(0))
 		})
 
 		g.It("increments written when Write is called", func() {
 			v := []byte("hello")
-			p := NewProgress(1000)
+			p := progress.NewProgress(1000)
 			_, err := p.Write(v)
 			g.Assert(err).IsNil()
-			g.Assert(p.Written()).Equal(int64(len(v)))
+			g.Assert(p.Written()).Equal(uint64(len(v)))
 		})
 
 		g.It("renders a progress bar", func() {
 			v := bytes.Repeat([]byte{' '}, 100)
-			p := NewProgress(1000)
+			p := progress.NewProgress(1000)
 			_, err := p.Write(v)
 			g.Assert(err).IsNil()
-			g.Assert(p.Written()).Equal(int64(len(v)))
+			g.Assert(p.Written()).Equal(uint64(len(v)))
 			g.Assert(p.Progress(25)).Equal("[==                       ] 100 B / 1000 B")
 		})
 
 		g.It("renders a progress bar when written exceeds total", func() {
 			v := bytes.Repeat([]byte{' '}, 1001)
-			p := NewProgress(1000)
+			p := progress.NewProgress(1000)
 			_, err := p.Write(v)
 			g.Assert(err).IsNil()
-			g.Assert(p.Written()).Equal(int64(len(v)))
+			g.Assert(p.Written()).Equal(uint64(len(v)))
 			g.Assert(p.Progress(25)).Equal("[=========================] 1001 B / 1000 B")
 		})
 	})

router/router.go

@@ -16,7 +16,7 @@ func Configure(m *wserver.Manager, client remote.Client) *gin.Engine {
 
 	router := gin.New()
 	router.Use(gin.Recovery())
-	router.SetTrustedProxies(config.Get().Api.TrustedProxies)
+	_ = router.SetTrustedProxies(config.Get().Api.TrustedProxies)
 	router.Use(middleware.AttachRequestID(), middleware.CaptureErrors(), middleware.SetAccessControlHeaders())
 	router.Use(middleware.AttachServerManager(m), middleware.AttachApiClient(client))
 	// @todo log this into a different file so you can setup IP blocking for abusive requests and such.
@@ -40,7 +40,7 @@ func Configure(m *wserver.Manager, client remote.Client) *gin.Engine {
 	router.GET("/download/file", getDownloadFile)
 	router.POST("/upload/file", postServerUploadFiles)
 
-	// This route is special it sits above all of the other requests because we are
+	// This route is special it sits above all the other requests because we are
 	// using a JWT to authorize access to it, therefore it needs to be publicly
 	// accessible.
 	router.GET("/api/servers/:server/ws", middleware.ServerExists(), getServerWebsocket)
@@ -48,16 +48,16 @@ func Configure(m *wserver.Manager, client remote.Client) *gin.Engine {
 	// This request is called by another daemon when a server is going to be transferred out.
 	// This request does not need the AuthorizationMiddleware as the panel should never call it
 	// and requests are authenticated through a JWT the panel issues to the other daemon.
-	router.GET("/api/servers/:server/archive", middleware.ServerExists(), getServerArchive)
+	router.POST("/api/transfers", postTransfers)
 
-	// All of the routes beyond this mount will use an authorization middleware
+	// All the routes beyond this mount will use an authorization middleware
 	// and will not be accessible without the correct Authorization header provided.
 	protected := router.Use(middleware.RequireAuthorization())
 	protected.POST("/api/update", postUpdateConfiguration)
 	protected.GET("/api/system", getSystemInformation)
 	protected.GET("/api/servers", getAllServers)
 	protected.POST("/api/servers", postCreateServer)
-	protected.POST("/api/transfer", postTransfer)
+	protected.DELETE("/api/transfers/:server", deleteTransfer)
 
 	// These are server specific routes, and require that the request be authorized, and
 	// that the server exist on the Daemon.
@@ -77,7 +77,8 @@ func Configure(m *wserver.Manager, client remote.Client) *gin.Engine {
 
 		// This archive request causes the archive to start being created
 		// this should only be triggered by the panel.
-		server.POST("/archive", postServerArchive)
+		server.POST("/transfer", postServerTransfer)
+		server.DELETE("/transfer", deleteServerTransfer)
 
 		files := server.Group("/files")
 		{

router/router_server.go

@@ -14,6 +14,7 @@ import (
 	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/router/tokens"
 	"github.com/pterodactyl/wings/server"
+	"github.com/pterodactyl/wings/server/transfer"
 )
 
 // Returns a single server from the collection of servers.
@@ -188,6 +189,17 @@ func deleteServer(c *gin.Context) {
 	// Immediately suspend the server to prevent a user from attempting
 	// to start it while this process is running.
 	s.Config().SetSuspended(true)
+
+	// Notify all websocket clients that the server is being deleted.
+	// This is useful for two reasons, one to tell clients not to bother
+	// retrying to connect to the websocket.  And two, for transfers when
+	// the server has been successfully transferred to another node, and
+	// the client needs to switch to the new node.
+	if s.IsTransferring() {
+		s.Events().Publish(server.TransferStatusEvent, transfer.StatusCompleted)
+	}
+	s.Events().Publish(server.DeletedEvent, nil)
+
 	s.CleanupForDestroy()
 
 	// Remove any pending remote file downloads for the server.
@@ -199,7 +211,7 @@ func deleteServer(c *gin.Context) {
 	// forcibly terminate it before removing the container, so we do not need to handle
 	// that here.
 	if err := s.Environment.Destroy(); err != nil {
-		WithError(c, err)
+		_ = WithError(c, err)
 		return
 	}
 
@@ -207,7 +219,7 @@ func deleteServer(c *gin.Context) {
 	// done in a separate process since failure is not the end of the world and can be
 	// manually cleaned up after the fact.
 	//
-	// In addition, servers with large amounts of files can take some time to finish deleting
+	// In addition, servers with large amounts of files can take some time to finish deleting,
 	// so we don't want to block the HTTP call while waiting on this.
 	go func(p string) {
 		if err := os.RemoveAll(p); err != nil {

router/router_server_transfer.go

@@ -0,0 +1,129 @@
+package router
+
+import (
+	"context"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/gin-gonic/gin"
+
+	"github.com/pterodactyl/wings/environment"
+	"github.com/pterodactyl/wings/router/middleware"
+	"github.com/pterodactyl/wings/server"
+	"github.com/pterodactyl/wings/server/installer"
+	"github.com/pterodactyl/wings/server/transfer"
+)
+
+// Data passed over to initiate a server transfer.
+type serverTransferRequest struct {
+	URL    string                  `binding:"required" json:"url"`
+	Token  string                  `binding:"required" json:"token"`
+	Server installer.ServerDetails `json:"server"`
+}
+
+// postServerTransfer handles the start of a transfer for a server.
+func postServerTransfer(c *gin.Context) {
+	var data serverTransferRequest
+	if err := c.BindJSON(&data); err != nil {
+		return
+	}
+
+	s := ExtractServer(c)
+
+	// Check if the server is already being transferred.
+	// There will be another endpoint for resetting this value either by deleting the
+	// server, or by canceling the transfer.
+	if s.IsTransferring() {
+		c.AbortWithStatusJSON(http.StatusConflict, gin.H{
+			"error": "A transfer is already in progress for this server.",
+		})
+		return
+	}
+
+	manager := middleware.ExtractManager(c)
+
+	notifyPanelOfFailure := func() {
+		if err := manager.Client().SetTransferStatus(context.Background(), s.ID(), false); err != nil {
+			s.Log().WithField("subsystem", "transfer").
+				WithField("status", false).
+				WithError(err).
+				Error("failed to set transfer status")
+		}
+
+		s.Events().Publish(server.TransferStatusEvent, "failure")
+		s.SetTransferring(false)
+	}
+
+	// Block the server from starting while we are transferring it.
+	s.SetTransferring(true)
+
+	// Ensure the server is offline. Sometimes a "No such container" error gets through
+	// which means the server is already stopped. We can ignore that.
+	if s.Environment.State() != environment.ProcessOfflineState {
+		if err := s.Environment.WaitForStop(
+			s.Context(),
+			time.Minute,
+			false,
+		); err != nil && !strings.Contains(strings.ToLower(err.Error()), "no such container") {
+			notifyPanelOfFailure()
+			s.Log().WithError(err).Error("failed to stop server for transfer")
+			return
+		}
+	}
+
+	// Create a new transfer instance for this server.
+	trnsfr := transfer.New(context.Background(), s)
+	transfer.Outgoing().Add(trnsfr)
+
+	go func() {
+		defer transfer.Outgoing().Remove(trnsfr)
+
+		if _, err := trnsfr.PushArchiveToTarget(data.URL, data.Token); err != nil {
+			notifyPanelOfFailure()
+
+			if err == context.Canceled {
+				trnsfr.Log().Debug("canceled")
+				trnsfr.SendMessage("Canceled.")
+				return
+			}
+
+			trnsfr.Log().WithError(err).Error("failed to push archive to target")
+			return
+		}
+
+		// DO NOT NOTIFY THE PANEL OF SUCCESS HERE. The only node that should send
+		// a success status is the destination node.  When we send a failure status,
+		// the panel will automatically cancel the transfer and attempt to reset
+		// the server state on the destination node, we just need to make sure
+		// we clean up our statuses for failure.
+
+		trnsfr.Log().Debug("transfer complete")
+	}()
+
+	c.Status(http.StatusAccepted)
+}
+
+// deleteServerTransfer cancels an outgoing transfer for a server.
+func deleteServerTransfer(c *gin.Context) {
+	s := ExtractServer(c)
+
+	if !s.IsTransferring() {
+		c.AbortWithStatusJSON(http.StatusConflict, gin.H{
+			"error": "Server is not currently being transferred.",
+		})
+		return
+	}
+
+	trnsfr := transfer.Outgoing().Get(s.ID())
+	if trnsfr == nil {
+		c.AbortWithStatusJSON(http.StatusConflict, gin.H{
+			"error": "Server is not currently being transferred.",
+		})
+		return
+	}
+
+	trnsfr.Cancel()
+
+	c.Status(http.StatusAccepted)
+}

router/router_system.go

@@ -10,9 +10,9 @@ import (
 	"github.com/gin-gonic/gin"
 
 	"github.com/pterodactyl/wings/config"
-	"github.com/pterodactyl/wings/installer"
 	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/server"
+	"github.com/pterodactyl/wings/server/installer"
 	"github.com/pterodactyl/wings/system"
 )
 
@@ -28,7 +28,7 @@ func getSystemInformation(c *gin.Context) {
 	c.JSON(http.StatusOK, i)
 }
 
-// Returns all of the servers that are registered and configured correctly on
+// Returns all the servers that are registered and configured correctly on
 // this wings instance.
 func getAllServers(c *gin.Context) {
 	servers := middleware.ExtractManager(c).All()
@@ -117,7 +117,7 @@ func postUpdateConfiguration(c *gin.Context) {
 	// Try to write this new configuration to the disk before updating our global
 	// state with it.
 	if err := config.WriteToDisk(cfg); err != nil {
-		WithError(c, err)
+		_ = WithError(c, err)
 		return
 	}
 	// Since we wrote it to the disk successfully now update the global configuration

router/router_transfer.go

@@ -1,53 +1,33 @@
 package router
 
 import (
-	"bufio"
+	"bytes"
 	"context"
 	"crypto/sha256"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"io"
+	"mime"
+	"mime/multipart"
 	"net/http"
 	"os"
-	"path/filepath"
-	"strconv"
 	"strings"
-	"time"
 
-	"emperror.dev/errors"
 	"github.com/apex/log"
 	"github.com/gin-gonic/gin"
 	"github.com/google/uuid"
-	"github.com/juju/ratelimit"
-	"github.com/mitchellh/colorstring"
 
-	"github.com/pterodactyl/wings/config"
-	"github.com/pterodactyl/wings/installer"
-	"github.com/pterodactyl/wings/remote"
 	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/router/tokens"
 	"github.com/pterodactyl/wings/server"
-	"github.com/pterodactyl/wings/server/filesystem"
+	"github.com/pterodactyl/wings/server/installer"
+	"github.com/pterodactyl/wings/server/transfer"
 )
 
-const progressWidth = 25
+// postTransfers .
-
+func postTransfers(c *gin.Context) {
-// Data passed over to initiate a server transfer.
-type serverTransferRequest struct {
-	ServerID string                  `binding:"required" json:"server_id"`
-	URL      string                  `binding:"required" json:"url"`
-	Token    string                  `binding:"required" json:"token"`
-	Server   installer.ServerDetails `json:"server"`
-}
-
-func getArchivePath(sID string) string {
-	return filepath.Join(config.Get().System.ArchiveDirectory, sID+".tar.gz")
-}
-
-// Returns the archive for a server so that it can be transferred to a new node.
-func getServerArchive(c *gin.Context) {
 	auth := strings.SplitN(c.GetHeader("Authorization"), " ", 2)
-
 	if len(auth) != 2 || auth[0] != "Bearer" {
 		c.Header("WWW-Authenticate", "Bearer")
 		c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{
@@ -62,458 +42,232 @@ func getServerArchive(c *gin.Context) {
 		return
 	}
 
-	s := ExtractServer(c)
-	if token.Subject != s.ID() {
-		c.AbortWithStatusJSON(http.StatusForbidden, gin.H{
-			"error": "Missing required token subject, or subject is not valid for the requested server.",
-		})
-		return
-	}
-
-	archivePath := getArchivePath(s.ID())
-
-	// Stat the archive file.
-	st, err := os.Lstat(archivePath)
-	if err != nil {
-		if !errors.Is(err, os.ErrNotExist) {
-			_ = WithError(c, err)
-			return
-		}
-		c.AbortWithStatus(http.StatusNotFound)
-		return
-	}
-
-	// Compute sha256 checksum.
-	h := sha256.New()
-	f, err := os.Open(archivePath)
-	if err != nil {
-		return
-	}
-	if _, err := io.Copy(h, bufio.NewReader(f)); err != nil {
-		_ = f.Close()
-		_ = WithError(c, err)
-		return
-	}
-	if err := f.Close(); err != nil {
-		_ = WithError(c, err)
-		return
-	}
-	checksum := hex.EncodeToString(h.Sum(nil))
-
-	// Stream the file to the client.
-	f, err = os.Open(archivePath)
-	if err != nil {
-		_ = WithError(c, err)
-		return
-	}
-	defer f.Close()
-
-	c.Header("X-Checksum", checksum)
-	c.Header("X-Mime-Type", "application/tar+gzip")
-	c.Header("Content-Length", strconv.Itoa(int(st.Size())))
-	c.Header("Content-Disposition", "attachment; filename="+strconv.Quote(s.ID()+".tar.gz"))
-	c.Header("Content-Type", "application/octet-stream")
-
-	_, _ = bufio.NewReader(f).WriteTo(c.Writer)
-}
-
-func postServerArchive(c *gin.Context) {
-	s := middleware.ExtractServer(c)
 	manager := middleware.ExtractManager(c)
-
+	u, err := uuid.Parse(token.Subject)
-	go func(s *server.Server) {
-		l := log.WithField("server", s.ID())
-
-		// This function automatically adds the Source Node prefix and Timestamp to the log
-		// output before sending it over the websocket.
-		sendTransferLog := func(data string) {
-			output := colorstring.Color(fmt.Sprintf("[yellow][bold]%s [Pterodactyl Transfer System] [Source Node]:[default] %s", time.Now().Format(time.RFC1123), data))
-			s.Events().Publish(server.TransferLogsEvent, output)
-		}
-
-		s.Events().Publish(server.TransferStatusEvent, "starting")
-		sendTransferLog("Attempting to archive server...")
-
-		hasError := true
-		defer func() {
-			if !hasError {
-				return
-			}
-
-			// Mark the server as not being transferred so it can actually be used.
-			s.SetTransferring(false)
-			s.Events().Publish(server.TransferStatusEvent, "failure")
-
-			sendTransferLog("Attempting to notify panel of archive failure..")
-			if err := manager.Client().SetArchiveStatus(s.Context(), s.ID(), false); err != nil {
-				if !remote.IsRequestError(err) {
-					sendTransferLog("Failed to notify panel of archive failure: " + err.Error())
-					l.WithField("error", err).Error("failed to notify panel of failed archive status")
-					return
-				}
-
-				sendTransferLog("Panel returned an error while notifying it of a failed archive: " + err.Error())
-				l.WithField("error", err.Error()).Error("panel returned an error when notifying it of a failed archive status")
-				return
-			}
-
-			sendTransferLog("Successfully notified panel of failed archive status")
-			l.Info("successfully notified panel of failed archive status")
-		}()
-
-		// Mark the server as transferring to prevent problems.
-		s.SetTransferring(true)
-
-		// Ensure the server is offline. Sometimes a "No such container" error gets through
-		// which means the server is already stopped. We can ignore that.
-		if err := s.Environment.WaitForStop(s.Context(), time.Minute, false); err != nil && !strings.Contains(strings.ToLower(err.Error()), "no such container") {
-			sendTransferLog("Failed to stop server, aborting transfer..")
-			l.WithField("error", err).Error("failed to stop server")
-			return
-		}
-
-		// Get the disk usage of the server (used to calculate the progress of the archive process)
-		rawSize, err := s.Filesystem().DiskUsage(true)
 	if err != nil {
-			sendTransferLog("Failed to get disk usage for server, aborting transfer..")
+		NewTrackedError(err).Abort(c)
-			l.WithField("error", err).Error("failed to get disk usage for server")
 		return
 	}
 
-		// Create an archive of the entire server's data directory.
+	// Get or create a new transfer instance for this server.
-		a := &filesystem.Archive{
+	var (
-			BasePath: s.Filesystem().Path(),
+		ctx    context.Context
-			Progress: filesystem.NewProgress(rawSize),
+		cancel context.CancelFunc
-		}
+	)
+	trnsfr := transfer.Incoming().Get(u.String())
+	if trnsfr == nil {
+		// TODO: should this use the request context?
+		trnsfr = transfer.New(c, nil)
 
-		// Send the archive progress to the websocket every 3 seconds.
+		ctx, cancel = context.WithCancel(trnsfr.Context())
-		ctx2, cancel := context.WithCancel(s.Context())
 		defer cancel()
-		go func(ctx context.Context, p *filesystem.Progress, t *time.Ticker) {
-			defer t.Stop()
-			for {
-				select {
-				case <-ctx.Done():
-					return
-				case <-t.C:
-					sendTransferLog("Archiving " + p.Progress(progressWidth))
-				}
-			}
-		}(ctx2, a.Progress, time.NewTicker(5*time.Second))
 
-		// Attempt to get an archive of the server.
+		i, err := installer.New(ctx, manager, installer.ServerDetails{
-		if err := a.Create(getArchivePath(s.ID())); err != nil {
+			UUID:              u.String(),
-			sendTransferLog("An error occurred while archiving the server: " + err.Error())
+			StartOnCompletion: false,
-			l.WithField("error", err).Error("failed to get transfer archive for server")
+		})
-			return
-		}
-
-		// Cancel the progress ticker.
-		cancel()
-
-		// Show 100% completion.
-		sendTransferLog("Archiving " + a.Progress.Progress(progressWidth))
-
-		sendTransferLog("Successfully created archive, attempting to notify panel..")
-		l.Info("successfully created server transfer archive, notifying panel..")
-
-		if err := manager.Client().SetArchiveStatus(s.Context(), s.ID(), true); err != nil {
-			if !remote.IsRequestError(err) {
-				sendTransferLog("Failed to notify panel of archive success: " + err.Error())
-				l.WithField("error", err).Error("failed to notify panel of successful archive status")
-				return
-			}
-
-			sendTransferLog("Panel returned an error while notifying it of a successful archive: " + err.Error())
-			l.WithField("error", err.Error()).Error("panel returned an error when notifying it of a successful archive status")
-			return
-		}
-
-		hasError = false
-
-		// This log may not be displayed by the client due to the status event being sent before or at the same time.
-		sendTransferLog("Successfully notified panel of successful archive status")
-
-		l.Info("successfully notified panel of successful transfer archive status")
-		s.Events().Publish(server.TransferStatusEvent, "archived")
-	}(s)
-
-	c.Status(http.StatusAccepted)
-}
-
-// Log helper function to attach all errors and info output to a consistently formatted
-// log string for easier querying.
-func (str serverTransferRequest) log() *log.Entry {
-	return log.WithField("subsystem", "transfers").WithField("server_id", str.ServerID)
-}
-
-// Downloads an archive from the machine that the server currently lives on.
-func (str serverTransferRequest) downloadArchive() (*http.Response, error) {
-	client := http.Client{Timeout: 0}
-	req, err := http.NewRequest(http.MethodGet, str.URL, nil)
 		if err != nil {
-		return nil, err
+			if err := manager.Client().SetTransferStatus(context.Background(), trnsfr.Server.ID(), false); err != nil {
+				trnsfr.Log().WithField("status", false).WithError(err).Error("failed to set transfer status")
 			}
-	req.Header.Set("Authorization", str.Token)
+			NewTrackedError(err).Abort(c)
-	res, err := client.Do(req) // lgtm [go/request-forgery]
-	if err != nil {
-		return nil, err
-	}
-	return res, nil
-}
-
-// Returns the path to the local archive on the system.
-func (str serverTransferRequest) path() string {
-	return getArchivePath(str.ServerID)
-}
-
-// Creates the archive location on this machine by first checking that the required file
-// does not already exist. If it does exist, the file is deleted and then re-created as
-// an empty file.
-func (str serverTransferRequest) createArchiveFile() (*os.File, error) {
-	p := str.path()
-	if _, err := os.Stat(p); err != nil {
-		if !os.IsNotExist(err) {
-			return nil, err
-		}
-	} else if err := os.Remove(p); err != nil {
-		return nil, err
-	}
-	return os.Create(p)
-}
-
-// Deletes the archive from the local filesystem. This is executed as a deferred function.
-func (str serverTransferRequest) removeArchivePath() {
-	p := str.path()
-	str.log().Debug("deleting temporary transfer archive")
-	if err := os.Remove(p); err != nil && !os.IsNotExist(err) {
-		str.log().WithField("path", p).WithField("error", err).Error("failed to delete temporary transfer archive file")
-		return
-	}
-	str.log().Debug("deleted temporary transfer archive successfully")
-}
-
-// Verifies that the SHA-256 checksum of the file on the local filesystem matches the
-// expected value from the transfer request. The string value returned is the computed
-// checksum on the system.
-func (str serverTransferRequest) verifyChecksum(matches string) (bool, string, error) {
-	f, err := os.Open(str.path())
-	if err != nil {
-		return false, "", err
-	}
-	defer f.Close()
-	h := sha256.New()
-	if _, err := io.Copy(h, bufio.NewReader(f)); err != nil {
-		return false, "", err
-	}
-	checksum := hex.EncodeToString(h.Sum(nil))
-	return checksum == matches, checksum, nil
-}
-
-// Sends a notification to the Panel letting it know what the status of this transfer is.
-func (str serverTransferRequest) sendTransferStatus(client remote.Client, successful bool) error {
-	lg := str.log().WithField("transfer_successful", successful)
-	lg.Info("notifying Panel of server transfer state")
-	if err := client.SetTransferStatus(context.Background(), str.ServerID, successful); err != nil {
-		lg.WithField("error", err).Error("error notifying panel of transfer state")
-		return err
-	}
-	lg.Debug("notified panel of transfer state")
-	return nil
-}
-
-// Initiates a transfer between two nodes for a server by downloading an archive from the
-// remote node and then applying the server details to this machine.
-func postTransfer(c *gin.Context) {
-	var data serverTransferRequest
-	if err := c.BindJSON(&data); err != nil {
 			return
 		}
 
-	manager := middleware.ExtractManager(c)
-	u, err := uuid.Parse(data.ServerID)
-	if err != nil {
-		_ = WithError(c, err)
-		return
-	}
-	// Force the server ID to be a valid UUID string at this point. If it is not an error
-	// is returned to the caller. This limits injection vulnerabilities that would cause
-	// the str.path() function to return a location not within the server archive directory.
-	data.ServerID = u.String()
-
-	data.log().Info("handling incoming server transfer request")
-	go func(data *serverTransferRequest) {
-		ctx := context.Background()
-		hasError := true
-
-		// Create a new server installer. This will only configure the environment and not
-		// run the installer scripts.
-		i, err := installer.New(ctx, manager, data.Server)
-		if err != nil {
-			_ = data.sendTransferStatus(manager.Client(), false)
-			data.log().WithField("error", err).Error("failed to validate received server data")
-			return
-		}
-
-		// This function automatically adds the Target Node prefix and Timestamp to the log output before sending it
-		// over the websocket.
-		sendTransferLog := func(data string) {
-			output := colorstring.Color(fmt.Sprintf("[yellow][bold]%s [Pterodactyl Transfer System] [Target Node]:[default] %s", time.Now().Format(time.RFC1123), data))
-			i.Server().Events().Publish(server.TransferLogsEvent, output)
-		}
-
-		// Mark the server as transferring to prevent problems later on during the process and
-		// then push the server into the global server collection for this instance.
 		i.Server().SetTransferring(true)
 		manager.Add(i.Server())
-		defer func(s *server.Server) {
-			// In the event that this transfer call fails, remove the server from the global
-			// server tracking so that we don't have a dangling instance.
-			if err := data.sendTransferStatus(manager.Client(), !hasError); hasError || err != nil {
-				sendTransferLog("Server transfer failed, check Wings logs for additional information.")
-				s.Events().Publish(server.TransferStatusEvent, "failure")
-				manager.Remove(func(match *server.Server) bool {
-					return match.ID() == s.ID()
-				})
 
-				// If the transfer status was successful but the request failed, act like the transfer failed.
+		// We add the transfer to the list of transfers once we have a server instance to use.
-				if !hasError && err != nil {
+		trnsfr.Server = i.Server()
-					// Delete all extracted files.
+		transfer.Incoming().Add(trnsfr)
-					if err := os.RemoveAll(s.Filesystem().Path()); err != nil && !os.IsNotExist(err) {
-						data.log().WithField("error", err).Warn("failed to delete local server files directory")
-					}
-				}
 	} else {
-				s.SetTransferring(false)
+		ctx, cancel = context.WithCancel(trnsfr.Context())
-				s.Events().Publish(server.TransferStatusEvent, "success")
-				sendTransferLog("Transfer completed.")
-			}
-		}(i.Server())
-
-		data.log().Info("downloading server archive from current server node")
-		sendTransferLog("Received incoming transfer from Panel, attempting to download archive from source node...")
-		res, err := data.downloadArchive()
-		if err != nil {
-			sendTransferLog("Failed to retrieve server archive from remote node: " + err.Error())
-			data.log().WithField("error", err).Error("failed to download archive for server transfer")
-			return
-		}
-		defer res.Body.Close()
-		if res.StatusCode != http.StatusOK {
-			data.log().WithField("error", err).WithField("status", res.StatusCode).Error("unexpected error response from transfer endpoint")
-			return
-		}
-
-		size := res.ContentLength
-		if size == 0 {
-			data.log().WithField("error", err).Error("received an archive response with Content-Length of 0")
-			return
-		}
-		sendTransferLog("Got server archive response from remote node. (Content-Length: " + strconv.Itoa(int(size)) + ")")
-		sendTransferLog("Creating local archive file...")
-		file, err := data.createArchiveFile()
-		if err != nil {
-			data.log().WithField("error", err).Error("failed to create archive file on local filesystem")
-			return
-		}
-
-		sendTransferLog("Writing archive to disk...")
-		data.log().Info("writing transfer archive to disk...")
-
-		progress := filesystem.NewProgress(size)
-		progress.SetWriter(file)
-
-		// Send the archive progress to the websocket every 3 seconds.
-		ctx2, cancel := context.WithCancel(ctx)
 		defer cancel()
-		go func(ctx context.Context, p *filesystem.Progress, t *time.Ticker) {
+	}
-			defer t.Stop()
+
+	// Any errors past this point (until the transfer is complete) will abort
+	// the transfer.
+
+	successful := false
+	defer func(ctx context.Context, trnsfr *transfer.Transfer) {
+		// Remove the transfer from the list of incoming transfers.
+		transfer.Incoming().Remove(trnsfr)
+
+		if !successful {
+			trnsfr.Server.Events().Publish(server.TransferStatusEvent, "failure")
+			manager.Remove(func(match *server.Server) bool {
+				return match.ID() == trnsfr.Server.ID()
+			})
+		}
+
+		if err := manager.Client().SetTransferStatus(context.Background(), trnsfr.Server.ID(), successful); err != nil {
+			// Only delete the files if the transfer actually failed, otherwise we could have
+			// unrecoverable data-loss.
+			if !successful && err != nil {
+				// Delete all extracted files.
+				go func(trnsfr *transfer.Transfer) {
+					if err := os.RemoveAll(trnsfr.Server.Filesystem().Path()); err != nil && !os.IsNotExist(err) {
+						trnsfr.Log().WithError(err).Warn("failed to delete local server files")
+					}
+				}(trnsfr)
+			}
+
+			trnsfr.Log().WithField("status", successful).WithError(err).Error("failed to set transfer status on panel")
+			return
+		}
+
+		trnsfr.Server.SetTransferring(false)
+		trnsfr.Server.Events().Publish(server.TransferStatusEvent, "success")
+	}(ctx, trnsfr)
+
+	mediaType, params, err := mime.ParseMediaType(c.GetHeader("Content-Type"))
+	if err != nil {
+		trnsfr.Log().Debug("failed to parse content type header")
+		NewTrackedError(err).Abort(c)
+		return
+	}
+
+	if !strings.HasPrefix(mediaType, "multipart/") {
+		trnsfr.Log().Debug("invalid content type")
+		NewTrackedError(fmt.Errorf("invalid content type \"%s\", expected \"multipart/form-data\"", mediaType)).Abort(c)
+		return
+	}
+
+	// Used to calculate the hash of the file as it is being uploaded.
+	h := sha256.New()
+
+	// Used to read the file and checksum from the request body.
+	mr := multipart.NewReader(c.Request.Body, params["boundary"])
+
+	// Loop through the parts of the request body and process them.
+	var (
+		hasArchive       bool
+		hasChecksum      bool
+		checksumVerified bool
+	)
+out:
 	for {
 		select {
 		case <-ctx.Done():
-					return
+			break out
-				case <-t.C:
+		default:
-					sendTransferLog("Downloading " + p.Progress(progressWidth))
+			p, err := mr.NextPart()
+			if err == io.EOF {
+				break out
 			}
-			}
+			if err != nil {
-		}(ctx2, progress, time.NewTicker(5*time.Second))
+				NewTrackedError(err).Abort(c)
-
-		var reader io.Reader
-		downloadLimit := float64(config.Get().System.Transfers.DownloadLimit) * 1024 * 1024
-		if downloadLimit > 0 {
-			// Wrap the body with a reader that is limited to the defined download limit speed.
-			reader = ratelimit.Reader(res.Body, ratelimit.NewBucketWithRate(downloadLimit, int64(downloadLimit)))
-		} else {
-			reader = res.Body
-		}
-
-		buf := make([]byte, 1024*4)
-		if _, err := io.CopyBuffer(progress, reader, buf); err != nil {
-			_ = file.Close()
-
-			sendTransferLog("Failed while writing archive file to disk: " + err.Error())
-			data.log().WithField("error", err).Error("failed to copy archive file to disk")
-			return
-		}
-		cancel()
-
-		// Show 100% completion.
-		sendTransferLog("Downloading " + progress.Progress(progressWidth))
-
-		if err := file.Close(); err != nil {
-			data.log().WithField("error", err).Error("unable to close archive file on local filesystem")
-			return
-		}
-		data.log().Info("finished writing transfer archive to disk")
-		sendTransferLog("Successfully wrote archive to disk.")
-
-		// Whenever the transfer fails or succeeds, delete the temporary transfer archive that
-		// was created on the disk.
-		defer data.removeArchivePath()
-
-		sendTransferLog("Verifying checksum of downloaded archive...")
-		data.log().Info("computing checksum of downloaded archive file")
-		expected := res.Header.Get("X-Checksum")
-		if matches, computed, err := data.verifyChecksum(expected); err != nil {
-			data.log().WithField("error", err).Error("encountered an error while calculating local filesystem archive checksum")
-			return
-		} else if !matches {
-			sendTransferLog("@@@@@ CHECKSUM VERIFICATION FAILED @@@@@")
-			sendTransferLog("  -   Source Checksum: " + expected)
-			sendTransferLog("  - Computed Checksum: " + computed)
-			data.log().WithField("expected_sum", expected).WithField("computed_checksum", computed).Error("checksum mismatch when verifying integrity of local archive")
 				return
 			}
 
-		// Create the server's environment.
+			name := p.FormName()
-		sendTransferLog("Creating server environment, this could take a while..")
+			switch name {
-		data.log().Info("creating server environment")
+			case "archive":
-		if err := i.Server().CreateEnvironment(); err != nil {
+				trnsfr.Log().Debug("received archive")
-			data.log().WithField("error", err).Error("failed to create server environment")
+
+				if err := trnsfr.Server.EnsureDataDirectoryExists(); err != nil {
+					NewTrackedError(err).Abort(c)
 					return
 				}
 
-		sendTransferLog("Server environment has been created, extracting transfer archive..")
+				tee := io.TeeReader(p, h)
-		data.log().Info("server environment configured, extracting transfer archive")
+				if err := trnsfr.Server.Filesystem().ExtractStreamUnsafe(ctx, "/", tee); err != nil {
-		if err := i.Server().Filesystem().DecompressFileUnsafe(ctx, "/", data.path()); err != nil {
+					NewTrackedError(err).Abort(c)
-			// Un-archiving failed, delete the server's data directory.
-			if err := os.RemoveAll(i.Server().Filesystem().Path()); err != nil && !os.IsNotExist(err) {
-				data.log().WithField("error", err).Warn("failed to delete local server files directory")
-			}
-			data.log().WithField("error", err).Error("failed to extract server archive")
 					return
 				}
 
-		// We mark the process as being successful here as if we fail to send a transfer success,
+				hasArchive = true
-		// then a transfer failure won't probably be successful either.
+			case "checksum":
-		//
+				trnsfr.Log().Debug("received checksum")
-		// It may be useful to retry sending the transfer success every so often just in case of a small
-		// hiccup or the fix of whatever error causing the success request to fail.
-		hasError = false
 
-		data.log().Info("archive extracted successfully, notifying Panel of status")
+				if !hasArchive {
-		sendTransferLog("Archive extracted successfully.")
+					NewTrackedError(errors.New("archive must be sent before the checksum")).Abort(c)
-	}(&data)
+					return
+				}
+
+				hasChecksum = true
+
+				v, err := io.ReadAll(p)
+				if err != nil {
+					NewTrackedError(err).Abort(c)
+					return
+				}
+
+				expected := make([]byte, hex.DecodedLen(len(v)))
+				n, err := hex.Decode(expected, v)
+				if err != nil {
+					NewTrackedError(err).Abort(c)
+					return
+				}
+				actual := h.Sum(nil)
+
+				trnsfr.Log().WithFields(log.Fields{
+					"expected": hex.EncodeToString(expected),
+					"actual":   hex.EncodeToString(actual),
+				}).Debug("checksums")
+
+				if !bytes.Equal(expected[:n], actual) {
+					NewTrackedError(errors.New("checksums don't match")).Abort(c)
+					return
+				}
+
+				trnsfr.Log().Debug("checksums match")
+				checksumVerified = true
+			default:
+				continue
+			}
+		}
+	}
+
+	if !hasArchive || !hasChecksum {
+		NewTrackedError(errors.New("missing archive or checksum")).Abort(c)
+		return
+	}
+
+	if !checksumVerified {
+		NewTrackedError(errors.New("checksums don't match")).Abort(c)
+		return
+	}
+
+	// Transfer is almost complete, we just want to ensure the environment is
+	// configured correctly.  We might want to not fail the transfer at this
+	// stage, but we will just to be safe.
+
+	// Ensure the server environment gets configured.
+	if err := trnsfr.Server.CreateEnvironment(); err != nil {
+		NewTrackedError(err).Abort(c)
+		return
+	}
+
+	// Changing this causes us to notify the panel about a successful transfer,
+	// rather than failing the transfer like we do by default.
+	successful = true
+
+	// The rest of the logic for ensuring the server is unlocked and everything
+	// is handled in the deferred function above.
+	trnsfr.Log().Debug("done!")
+}
+
+// deleteTransfer cancels an incoming transfer for a server.
+func deleteTransfer(c *gin.Context) {
+	s := ExtractServer(c)
+
+	if !s.IsTransferring() {
+		c.AbortWithStatusJSON(http.StatusConflict, gin.H{
+			"error": "Server is not currently being transferred.",
+		})
+		return
+	}
+
+	trnsfr := transfer.Incoming().Get(s.ID())
+	if trnsfr == nil {
+		c.AbortWithStatusJSON(http.StatusConflict, gin.H{
+			"error": "Server is not currently being transferred.",
+		})
+		return
+	}
+
+	trnsfr.Cancel()
 
 	c.Status(http.StatusAccepted)
 }

server/backup/backup_local.go

@@ -66,7 +66,7 @@ func (b *LocalBackup) Generate(ctx context.Context, basePath, ignore string) (*A
 	}
 
 	b.log().WithField("path", b.Path()).Info("creating backup for server")
-	if err := a.Create(b.Path()); err != nil {
+	if err := a.Create(ctx, b.Path()); err != nil {
 		return nil, err
 	}
 	b.log().Info("created backup successfully")

server/backup/backup_s3.go

@@ -57,7 +57,7 @@ func (s *S3Backup) Generate(ctx context.Context, basePath, ignore string) (*Arch
 	}
 
 	s.log().WithField("path", s.Path()).Info("creating backup for server")
-	if err := a.Create(s.Path()); err != nil {
+	if err := a.Create(ctx, s.Path()); err != nil {
 		return nil, err
 	}
 	s.log().Info("created backup successfully")

server/events.go

@@ -5,8 +5,7 @@ import (
 	"github.com/pterodactyl/wings/system"
 )
 
-// Defines all of the possible output events for a server.
+// Defines all the possible output events for a server.
-// noinspection GoNameStartsWithPackageName
 const (
 	DaemonMessageEvent          = "daemon message"
 	InstallOutputEvent          = "install output"
@@ -19,6 +18,7 @@ const (
 	BackupCompletedEvent        = "backup completed"
 	TransferLogsEvent           = "transfer logs"
 	TransferStatusEvent         = "transfer status"
+	DeletedEvent                = "deleted"
 )
 
 // Events returns the server's emitter instance.

server/filesystem/archive.go

@@ -2,13 +2,13 @@ package filesystem
 
 import (
 	"archive/tar"
+	"context"
 	"io"
 	"io/fs"
 	"os"
 	"path/filepath"
 	"strings"
 	"sync"
-	"sync/atomic"
 
 	"emperror.dev/errors"
 	"github.com/apex/log"
@@ -18,7 +18,7 @@ import (
 	ignore "github.com/sabhiram/go-gitignore"
 
 	"github.com/pterodactyl/wings/config"
-	"github.com/pterodactyl/wings/system"
+	"github.com/pterodactyl/wings/internal/progress"
 )
 
 const memory = 4 * 1024
@@ -33,13 +33,13 @@ var pool = sync.Pool{
 // TarProgress .
 type TarProgress struct {
 	*tar.Writer
-	p *Progress
+	p *progress.Progress
 }
 
 // NewTarProgress .
-func NewTarProgress(w *tar.Writer, p *Progress) *TarProgress {
+func NewTarProgress(w *tar.Writer, p *progress.Progress) *TarProgress {
 	if p != nil {
-		p.w = w
+		p.Writer = w
 	}
 	return &TarProgress{
 		Writer: w,
@@ -47,6 +47,7 @@ func NewTarProgress(w *tar.Writer, p *Progress) *TarProgress {
 	}
 }
 
+// Write .
 func (p *TarProgress) Write(v []byte) (int, error) {
 	if p.p == nil {
 		return p.Writer.Write(v)
@@ -54,84 +55,6 @@ func (p *TarProgress) Write(v []byte) (int, error) {
 	return p.p.Write(v)
 }
 
-// Progress is used to track the progress of any I/O operation that are being
-// performed.
-type Progress struct {
-	// written is the total size of the files that have been written to the writer.
-	written int64
-	// Total is the total size of the archive in bytes.
-	total int64
-	// w .
-	w io.Writer
-}
-
-// NewProgress .
-func NewProgress(total int64) *Progress {
-	return &Progress{total: total}
-}
-
-// SetWriter sets the writer progress will forward writes to.
-// NOTE: This function is not thread safe.
-func (p *Progress) SetWriter(w io.Writer) {
-	p.w = w
-}
-
-// Written returns the total number of bytes written.
-// This function should be used when the progress is tracking data being written.
-func (p *Progress) Written() int64 {
-	return atomic.LoadInt64(&p.written)
-}
-
-// Total returns the total size in bytes.
-func (p *Progress) Total() int64 {
-	return atomic.LoadInt64(&p.total)
-}
-
-// Write totals the number of bytes that have been written to the writer.
-func (p *Progress) Write(v []byte) (int, error) {
-	n := len(v)
-	atomic.AddInt64(&p.written, int64(n))
-	if p.w != nil {
-		return p.w.Write(v)
-	}
-	return n, nil
-}
-
-// Progress returns a formatted progress string for the current progress.
-func (p *Progress) Progress(width int) string {
-	// current = 100 (Progress, dynamic)
-	// total = 1000 (Content-Length, dynamic)
-	// width = 25 (Number of ticks to display, static)
-	// widthPercentage = 100 / width (What percentage does each tick represent, static)
-	//
-	// percentageDecimal = current / total = 0.1
-	// percentage = percentageDecimal * 100 = 10%
-	// ticks = percentage / widthPercentage = 2.5
-	//
-	// ticks is a float64, so we cast it to an int which rounds it down to 2.
-
-	// Values are cast to floats to prevent integer division.
-	current := p.Written()
-	total := p.Total()
-	// width := is passed as a parameter
-	widthPercentage := float64(100) / float64(width)
-	percentageDecimal := float64(current) / float64(total)
-	percentage := percentageDecimal * 100
-	ticks := int(percentage / widthPercentage)
-
-	// Ensure that we never get a negative number of ticks, this will prevent strings#Repeat
-	// from panicking.  A negative number of ticks is likely to happen when the total size is
-	// inaccurate, such as when we are going off of rough disk usage calculation.
-	if ticks < 0 {
-		ticks = 0
-	} else if ticks > width {
-		ticks = width
-	}
-
-	bar := strings.Repeat("=", ticks) + strings.Repeat(" ", width-ticks)
-	return "[" + bar + "] " + system.FormatBytes(current) + " / " + system.FormatBytes(total)
-}
-
 type Archive struct {
 	// BasePath is the absolute path to create the archive from where Files and Ignore are
 	// relative to.
@@ -146,12 +69,12 @@ type Archive struct {
 	Files []string
 
 	// Progress wraps the writer of the archive to pass through the progress tracker.
-	Progress *Progress
+	Progress *progress.Progress
 }
 
 // Create creates an archive at dst with all the files defined in the
 // included Files array.
-func (a *Archive) Create(dst string) error {
+func (a *Archive) Create(ctx context.Context, dst string) error {
 	f, err := os.OpenFile(dst, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o600)
 	if err != nil {
 		return err
@@ -169,6 +92,11 @@ func (a *Archive) Create(dst string) error {
 		writer = f
 	}
 
+	return a.Stream(ctx, writer)
+}
+
+// Stream .
+func (a *Archive) Stream(ctx context.Context, w io.Writer) error {
 	// Choose which compression level to use based on the compression_level configuration option
 	var compressionLevel int
 	switch config.Get().System.Backups.CompressionLevel {
@@ -183,7 +111,7 @@ func (a *Archive) Create(dst string) error {
 	}
 
 	// Create a new gzip writer around the file.
-	gw, _ := pgzip.NewWriterLevel(writer, compressionLevel)
+	gw, _ := pgzip.NewWriterLevel(w, compressionLevel)
 	_ = gw.SetConcurrency(1<<20, 1)
 	defer gw.Close()
 
@@ -197,16 +125,16 @@ func (a *Archive) Create(dst string) error {
 	options := &godirwalk.Options{
 		FollowSymbolicLinks: false,
 		Unsorted:            true,
-		Callback:            a.callback(pw),
 	}
 
 	// If we're specifically looking for only certain files, or have requested
 	// that certain files be ignored we'll update the callback function to reflect
 	// that request.
+	var callback godirwalk.WalkFunc
 	if len(a.Files) == 0 && len(a.Ignore) > 0 {
 		i := ignore.CompileIgnoreLines(strings.Split(a.Ignore, "\n")...)
 
-		options.Callback = a.callback(pw, func(_ string, rp string) error {
+		callback = a.callback(pw, func(_ string, rp string) error {
 			if i.MatchesPath(rp) {
 				return godirwalk.SkipThis
 			}
@@ -214,7 +142,19 @@ func (a *Archive) Create(dst string) error {
 			return nil
 		})
 	} else if len(a.Files) > 0 {
-		options.Callback = a.withFilesCallback(pw)
+		callback = a.withFilesCallback(pw)
+	} else {
+		callback = a.callback(pw)
+	}
+
+	// Set the callback function, wrapped with support for context cancellation.
+	options.Callback = func(path string, de *godirwalk.Dirent) error {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+			return callback(path, de)
+		}
 	}
 
 	// Recursively walk the path we are archiving.

server/filesystem/compress.go

@@ -6,6 +6,7 @@ import (
 	"compress/gzip"
 	"context"
 	"fmt"
+	"io"
 	iofs "io/fs"
 	"os"
 	"path"
@@ -21,7 +22,7 @@ import (
 	"github.com/mholt/archiver/v4"
 )
 
-// CompressFiles compresses all of the files matching the given paths in the
+// CompressFiles compresses all the files matching the given paths in the
 // specified directory. This function also supports passing nested paths to only
 // compress certain files and folders when working in a larger directory. This
 // effectively creates a local backup, but rather than ignoring specific files
@@ -36,7 +37,7 @@ func (fs *Filesystem) CompressFiles(dir string, paths []string) (os.FileInfo, er
 		return nil, err
 	}
 
-	// Take all of the paths passed in and merge them together with the root directory we've gotten.
+	// Take all the paths passed in and merge them together with the root directory we've gotten.
 	for i, p := range paths {
 		paths[i] = filepath.Join(cleanedRootDir, p)
 	}
@@ -52,7 +53,7 @@ func (fs *Filesystem) CompressFiles(dir string, paths []string) (os.FileInfo, er
 		fmt.Sprintf("archive-%s.tar.gz", strings.ReplaceAll(time.Now().Format(time.RFC3339), ":", "")),
 	)
 
-	if err := a.Create(d); err != nil {
+	if err := a.Create(context.Background(), d); err != nil {
 		return nil, err
 	}
 
@@ -147,6 +148,7 @@ func (fs *Filesystem) DecompressFileUnsafe(ctx context.Context, dir string, file
 	if err != nil {
 		return err
 	}
+	// TODO: defer file close?
 
 	// Identify the type of archive we are dealing with.
 	format, input, err := archiver.Identify(filepath.Base(file), f)
@@ -157,13 +159,49 @@ func (fs *Filesystem) DecompressFileUnsafe(ctx context.Context, dir string, file
 		return err
 	}
 
+	return fs.extractStream(ctx, extractStreamOptions{
+		Directory: dir,
+		Format:    format,
+		Reader:    input,
+	})
+}
+
+// ExtractStreamUnsafe .
+func (fs *Filesystem) ExtractStreamUnsafe(ctx context.Context, dir string, r io.Reader) error {
+	format, input, err := archiver.Identify("archive.tar.gz", r)
+	if err != nil {
+		if errors.Is(err, archiver.ErrNoMatch) {
+			return newFilesystemError(ErrCodeUnknownArchive, err)
+		}
+		return err
+	}
+
+	return fs.extractStream(ctx, extractStreamOptions{
+		Directory: dir,
+		Format:    format,
+		Reader:    input,
+	})
+}
+
+type extractStreamOptions struct {
+	// The directory to extract the archive to.
+	Directory string
+	// File name of the archive.
+	FileName string
+	// Format of the archive.
+	Format archiver.Format
+	// Reader for the archive.
+	Reader io.Reader
+}
+
+func (fs *Filesystem) extractStream(ctx context.Context, opts extractStreamOptions) error {
 	// Decompress and extract archive
-	if ex, ok := format.(archiver.Extractor); ok {
+	if ex, ok := opts.Format.(archiver.Extractor); ok {
-		return ex.Extract(ctx, input, nil, func(ctx context.Context, f archiver.File) error {
+		return ex.Extract(ctx, opts.Reader, nil, func(ctx context.Context, f archiver.File) error {
 			if f.IsDir() {
 				return nil
 			}
-			p := filepath.Join(dir, ExtractNameFromArchive(f))
+			p := filepath.Join(opts.Directory, ExtractNameFromArchive(f))
 			// If it is ignored, just don't do anything with the file and skip over it.
 			if err := fs.IsIgnored(p); err != nil {
 				return nil
@@ -174,20 +212,19 @@ func (fs *Filesystem) DecompressFileUnsafe(ctx context.Context, dir string, file
 			}
 			defer r.Close()
 			if err := fs.Writefile(p, r); err != nil {
-				return wrapError(err, file)
+				return wrapError(err, opts.FileName)
 			}
 			// Update the file permissions to the one set in the archive.
 			if err := fs.Chmod(p, f.Mode()); err != nil {
-				return wrapError(err, file)
+				return wrapError(err, opts.FileName)
 			}
 			// Update the file modification time to the one set in the archive.
 			if err := fs.Chtimes(p, f.ModTime(), f.ModTime()); err != nil {
-				return wrapError(err, file)
+				return wrapError(err, opts.FileName)
 			}
 			return nil
 		})
 	}
-
 	return nil
 }
 

server/transfer/archive.go

@@ -0,0 +1,52 @@
+package transfer
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"github.com/pterodactyl/wings/internal/progress"
+	"github.com/pterodactyl/wings/server/filesystem"
+)
+
+// Archive returns an archive that can be used to stream the contents of the
+// contents of a server.
+func (t *Transfer) Archive() (*Archive, error) {
+	if t.archive == nil {
+		// Get the disk usage of the server (used to calculate the progress of the archive process)
+		rawSize, err := t.Server.Filesystem().DiskUsage(true)
+		if err != nil {
+			return nil, fmt.Errorf("transfer: failed to get server disk usage: %w", err)
+		}
+
+		// Create a new archive instance and assign it to the transfer.
+		t.archive = NewArchive(t, uint64(rawSize))
+	}
+
+	return t.archive, nil
+}
+
+// Archive represents an archive used to transfer the contents of a server.
+type Archive struct {
+	archive *filesystem.Archive
+}
+
+// NewArchive returns a new archive associated with the given transfer.
+func NewArchive(t *Transfer, size uint64) *Archive {
+	return &Archive{
+		archive: &filesystem.Archive{
+			BasePath: t.Server.Filesystem().Path(),
+			Progress: progress.NewProgress(size),
+		},
+	}
+}
+
+// Stream returns a reader that can be used to stream the contents of the archive.
+func (a *Archive) Stream(ctx context.Context, w io.Writer) error {
+	return a.archive.Stream(ctx, w)
+}
+
+// Progress returns the current progress of the archive.
+func (a *Archive) Progress() *progress.Progress {
+	return a.archive.Progress
+}

server/transfer/doc.go

@@ -0,0 +1,4 @@
+// Package transfer handles all logic related to transferring servers between
+// two nodes. This includes the logic for archiving a server on the source node
+// and logic for importing a server from the source node into the target node.
+package transfer

server/transfer/manager.go

@@ -0,0 +1,57 @@
+package transfer
+
+import (
+	"sync"
+)
+
+var (
+	incomingTransfers = NewManager()
+	outgoingTransfers = NewManager()
+)
+
+// Incoming returns a transfer manager for incoming transfers.
+func Incoming() *Manager {
+	return incomingTransfers
+}
+
+// Outgoing returns a transfer manager for outgoing transfers.
+func Outgoing() *Manager {
+	return outgoingTransfers
+}
+
+// Manager manages transfers.
+type Manager struct {
+	mu        sync.RWMutex
+	transfers map[string]*Transfer
+}
+
+// NewManager returns a new transfer manager.
+func NewManager() *Manager {
+	return &Manager{
+		transfers: make(map[string]*Transfer),
+	}
+}
+
+// Add adds a transfer to the manager.
+func (m *Manager) Add(transfer *Transfer) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	m.transfers[transfer.Server.ID()] = transfer
+}
+
+// Remove removes a transfer from the manager.
+func (m *Manager) Remove(transfer *Transfer) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	delete(m.transfers, transfer.Server.ID())
+}
+
+// Get gets a transfer from the manager using a server ID.
+func (m *Manager) Get(id string) *Transfer {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+
+	return m.transfers[id]
+}

server/transfer/source.go

@@ -0,0 +1,159 @@
+package transfer
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"mime/multipart"
+	"net/http"
+	"time"
+
+	"github.com/pterodactyl/wings/internal/progress"
+)
+
+// PushArchiveToTarget POSTs the archive to the target node and returns the
+// response body.
+func (t *Transfer) PushArchiveToTarget(url, token string) ([]byte, error) {
+	ctx, cancel := context.WithCancel(t.ctx)
+	defer cancel()
+
+	t.SendMessage("Preparing to stream server data to destination...")
+	t.SetStatus(StatusProcessing)
+
+	a, err := t.Archive()
+	if err != nil {
+		t.Error(err, "Failed to get archive for transfer.")
+		return nil, errors.New("failed to get archive for transfer")
+	}
+
+	t.SendMessage("Streaming archive to destination...")
+
+	// Send the upload progress to the websocket every 5 seconds.
+	ctx2, cancel2 := context.WithCancel(ctx)
+	defer cancel2()
+	go func(ctx context.Context, p *progress.Progress, tc *time.Ticker) {
+		defer tc.Stop()
+
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case <-tc.C:
+				t.SendMessage("Uploading " + p.Progress(25))
+			}
+		}
+	}(ctx2, a.Progress(), time.NewTicker(5*time.Second))
+
+	// Create a new request using the pipe as the body.
+	body, writer := io.Pipe()
+	defer body.Close()
+	defer writer.Close()
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, body)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Authorization", token)
+
+	// Create a new multipart writer that writes the archive to the pipe.
+	mp := multipart.NewWriter(writer)
+	defer mp.Close()
+	req.Header.Set("Content-Type", mp.FormDataContentType())
+
+	// Create a new goroutine to write the archive to the pipe used by the
+	// multipart writer.
+	errChan := make(chan error)
+	go func() {
+		defer close(errChan)
+		defer writer.Close()
+		defer mp.Close()
+
+		src, pw := io.Pipe()
+		defer src.Close()
+		defer pw.Close()
+
+		h := sha256.New()
+		tee := io.TeeReader(src, h)
+
+		dest, err := mp.CreateFormFile("archive", "archive.tar.gz")
+		if err != nil {
+			errChan <- errors.New("failed to create form file")
+			return
+		}
+
+		ch := make(chan error)
+		go func() {
+			defer close(ch)
+
+			if _, err := io.Copy(dest, tee); err != nil {
+				ch <- fmt.Errorf("failed to stream archive to destination: %w", err)
+				return
+			}
+
+			t.Log().Debug("finished copying dest to tee")
+		}()
+
+		if err := a.Stream(ctx, pw); err != nil {
+			errChan <- errors.New("failed to stream archive to pipe")
+			return
+		}
+		t.Log().Debug("finished streaming archive to pipe")
+
+		// Close the pipe writer early to release resources and ensure that the data gets flushed.
+		_ = pw.Close()
+
+		// Wait for the copy to finish before we continue.
+		t.Log().Debug("waiting on copy to finish")
+		if err := <-ch; err != nil {
+			errChan <- err
+			return
+		}
+
+		if err := mp.WriteField("checksum", hex.EncodeToString(h.Sum(nil))); err != nil {
+			errChan <- errors.New("failed to stream checksum")
+			return
+		}
+
+		cancel2()
+		t.SendMessage("Finished streaming archive to destination.")
+
+		if err := mp.Close(); err != nil {
+			t.Log().WithError(err).Error("error while closing multipart writer")
+		}
+		t.Log().Debug("closed multipart writer")
+	}()
+
+	t.Log().Debug("sending archive to destination")
+	client := http.Client{Timeout: 0}
+	res, err := client.Do(req)
+	t.Log().Debug("waiting for stream to complete")
+	select {
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	case err2 := <-errChan:
+		t.Log().Debug("stream completed")
+		if err != nil || err2 != nil {
+			if err == context.Canceled {
+				return nil, err
+			}
+
+			t.Log().WithError(err).Debug("failed to send archive to destination")
+			return nil, fmt.Errorf("http error: %w, multipart error: %v", err, err2)
+		}
+		defer res.Body.Close()
+		t.Log().Debug("received response from destination")
+
+		v, err := io.ReadAll(res.Body)
+		if err != nil {
+			return nil, fmt.Errorf("failed to read response body: %w", err)
+		}
+
+		if res.StatusCode != http.StatusOK {
+			return nil, errors.New(string(v))
+		}
+
+		return v, nil
+	}
+}

server/transfer/transfer.go

@@ -0,0 +1,128 @@
+package transfer
+
+import (
+	"context"
+	"time"
+
+	"github.com/apex/log"
+	"github.com/mitchellh/colorstring"
+
+	"github.com/pterodactyl/wings/server"
+	"github.com/pterodactyl/wings/system"
+)
+
+// Status represents the current status of a transfer.
+type Status string
+
+// String satisfies the fmt.Stringer interface.
+func (s Status) String() string {
+	return string(s)
+}
+
+const (
+	// StatusPending is the status of a transfer when it is first created.
+	StatusPending Status = "pending"
+	// StatusProcessing is the status of a transfer when it is currently in
+	// progress, such as when the archive is being streamed to the target node.
+	StatusProcessing Status = "processing"
+
+	// StatusCancelling is the status of a transfer when it is in the process of
+	// being cancelled.
+	StatusCancelling Status = "cancelling"
+
+	// StatusCancelled is the final status of a transfer when it has been
+	// cancelled.
+	StatusCancelled Status = "cancelled"
+	// StatusFailed is the final status of a transfer when it has failed.
+	StatusFailed Status = "failed"
+	// StatusCompleted is the final status of a transfer when it has completed.
+	StatusCompleted Status = "completed"
+)
+
+// Transfer represents a transfer of a server from one node to another.
+type Transfer struct {
+	// ctx is the context for the transfer.
+	ctx context.Context
+	// cancel is used to cancel all ongoing transfer operations for the server.
+	cancel *context.CancelFunc
+
+	// Server associated with the transfer.
+	Server *server.Server
+	// status of the transfer.
+	status *system.Atomic[Status]
+
+	// archive is the archive that is being created for the transfer.
+	archive *Archive
+}
+
+// New returns a new transfer instance for the given server.
+func New(ctx context.Context, s *server.Server) *Transfer {
+	ctx, cancel := context.WithCancel(ctx)
+
+	return &Transfer{
+		ctx:    ctx,
+		cancel: &cancel,
+
+		Server: s,
+		status: system.NewAtomic(StatusPending),
+	}
+}
+
+// Context returns the context for the transfer.
+func (t *Transfer) Context() context.Context {
+	return t.ctx
+}
+
+// Cancel cancels the transfer.
+func (t *Transfer) Cancel() {
+	status := t.Status()
+	if status == StatusCancelling ||
+		status == StatusCancelled ||
+		status == StatusCompleted ||
+		status == StatusFailed {
+		return
+	}
+
+	if t.cancel == nil {
+		return
+	}
+
+	t.SetStatus(StatusCancelling)
+	(*t.cancel)()
+}
+
+// Status returns the current status of the transfer.
+func (t *Transfer) Status() Status {
+	return t.status.Load()
+}
+
+// SetStatus sets the status of the transfer.
+func (t *Transfer) SetStatus(s Status) {
+	// TODO: prevent certain status changes from happening.
+	// If we are cancelling, then we can't go back to processing.
+	t.status.Store(s)
+
+	t.Server.Events().Publish(server.TransferStatusEvent, s)
+}
+
+// SendMessage sends a message to the server's console.
+func (t *Transfer) SendMessage(v string) {
+	t.Server.Events().Publish(
+		server.TransferLogsEvent,
+		colorstring.Color("[yellow][bold]"+time.Now().Format(time.RFC1123)+" [Transfer System] [Source Node]:[default] "+v),
+	)
+}
+
+// Error logs an error that occurred on the source node.
+func (t *Transfer) Error(err error, v string) {
+	t.Log().WithError(err).Error(v)
+	t.SendMessage(v)
+}
+
+// Log returns a logger for the transfer.
+func (t *Transfer) Log() *log.Entry {
+	if t.Server == nil {
+		return log.WithField("subsystem", "transfer")
+	}
+	return t.Server.Log().WithField("subsystem", "transfer")
+}

system/utils.go

@@ -120,7 +120,7 @@ func ScanReader(r io.Reader, callback func(line []byte)) error {
 	return nil
 }
 
-func FormatBytes(b int64) string {
+func FormatBytes[T int | int16 | int32 | int64 | uint | uint16 | uint32 | uint64](b T) string {
 	if b < 1024 {
 		return fmt.Sprintf("%d B", b)
 	}
@@ -188,14 +188,14 @@ func NewAtomicString(v string) *AtomicString {
 	return &AtomicString{v: v}
 }
 
-// Stores the string value passed atomically.
+// Store stores the string value passed atomically.
 func (as *AtomicString) Store(v string) {
 	as.mu.Lock()
 	as.v = v
 	as.mu.Unlock()
 }
 
-// Loads the string value and returns it.
+// Load loads the string value and returns it.
 func (as *AtomicString) Load() string {
 	as.mu.RLock()
 	defer as.mu.RUnlock()
@@ -211,3 +211,41 @@ func (as *AtomicString) UnmarshalJSON(b []byte) error {
 func (as *AtomicString) MarshalJSON() ([]byte, error) {
 	return json.Marshal(as.Load())
 }
+
+type Atomic[T any] struct {
+	v  T
+	mu sync.RWMutex
+}
+
+func NewAtomic[T any](v T) *Atomic[T] {
+	return &Atomic[T]{v: v}
+}
+
+// Store stores the string value passed atomically.
+func (a *Atomic[T]) Store(v T) {
+	a.mu.Lock()
+	defer a.mu.Unlock()
+
+	a.v = v
+}
+
+// Load loads the string value and returns it.
+func (a *Atomic[T]) Load() T {
+	a.mu.RLock()
+	defer a.mu.RUnlock()
+
+	return a.v
+}
+
+// UnmarshalJSON unmarshals the JSON value into the Atomic[T] value.
+func (a *Atomic[T]) UnmarshalJSON(b []byte) error {
+	a.mu.Lock()
+	defer a.mu.Unlock()
+
+	return json.Unmarshal(b, &a.v)
+}
+
+// MarshalJSON marshals the Atomic[T] value into JSON.
+func (a *Atomic[T]) MarshalJSON() ([]byte, error) {
+	return json.Marshal(a.Load())
+}