Updated VM import/export to be simpler and more robust

src/exec/VirtCopyIn.go → src/exec/VirtTarIn.go

@@ -8,33 +8,31 @@ import (
 )
 
 const (
-	virtcopyinBinary = "virt-copy-in"
+	virtTarInBinary = "virt-tar-in"
 )
 
-// Check virt-copy-in is available.
-func CheckVirtCopyIn() error {
-	output, err := exec.Command(virtcopyinBinary, "--version").Output()
+// Checks virt-tar-in is available.
+func CheckVirtTarIn() error {
+	output, err := exec.Command(virtTarInBinary, "--version").Output()
     if err != nil {
-        return errors.New(virtcopyinBinary+" is required but not found. On Ubuntu/Debian, it can be installed with \"sudo apt-get install guestfish\".")
+        return errors.New(virtTarInBinary+" is required but not found. On Ubuntu/Debian, it can be installed with \"sudo apt-get install guestfish\".")
 	}
 	out := string(output)
 	lines := strings.Split(out, "\n")
 	fields := strings.Split(lines[0], " ")
 	if len(fields) < 2 {
-		return errors.New("Failed extracting "+virtcopyinBinary+" version number!")
+		return errors.New("Failed extracting "+virtTarInBinary+" version number!")
 	}
 	cmd := fields[0]
-	if cmd != virtcopyinBinary {
-		return errors.New(virtcopyinBinary+" is required, but not found.")
+	if cmd != virtTarInBinary {
+		return errors.New(virtTarInBinary+" is required, but not found.")
 	}
 	return nil
 }
 
-// Creates a virt-copy-in command that recursively copy a directory on the host (localDir)
-// into a directory on the VM's filesystem (vmDir).
-// Note: both directories must exist, otherwise the command will fail.
-func CopyToVM(vmDiskFile, localDir, vmDir string) error {
-	cmd := exec.Command(virtcopyinBinary, "-a", vmDiskFile, localDir, vmDir)
+// Runs virt-tar-in which unarchive a local archive into a directory (vmDir) inside the VM disk.
+func CopyToVM(vmDiskFile, tarFile, vmDir string) error {
+	cmd := exec.Command(virtTarInBinary, "-a", vmDiskFile, tarFile, vmDir)
 	stdoutStderr, err := cmd.CombinedOutput()
 	if err != nil {
 		output := fmt.Sprintf("[%s]", stdoutStderr)

src/exec/VirtCopyOut.go → src/exec/VirtTarOut.go

@@ -8,33 +8,34 @@ import (
 )
 
 const (
-	virtcopyoutBinary = "virt-copy-out"
+	virtTarOutBinary = "virt-tar-out"
 )
 
-// Check virt-copy-out is available.
+// Checks virt-tar-out is available.
 func CheckVirtCopyOut() error {
-	output, err := exec.Command(virtcopyoutBinary, "--version").Output()
+	output, err := exec.Command(virtTarOutBinary, "--version").Output()
     if err != nil {
-        return errors.New(virtcopyoutBinary+" is required but not found. On Ubuntu/Debian, it can be installed with \"sudo apt-get install guestfish\".")
+        return errors.New(virtTarOutBinary+" is required but not found. On Ubuntu/Debian, it can be installed with \"sudo apt-get install guestfish\".")
 	}
 	out := string(output)
 	lines := strings.Split(out, "\n")
 	fields := strings.Split(lines[0], " ")
 	if len(fields) < 2 {
-		return errors.New("Failed extracting "+virtcopyoutBinary+" version number!")
+		return errors.New("Failed extracting "+virtTarOutBinary+" version number!")
 	}
 	cmd := fields[0]
-	if cmd != virtcopyoutBinary {
-		return errors.New(virtcopyoutBinary+" is required, but not found.")
+	if cmd != virtTarOutBinary {
+		return errors.New(virtTarOutBinary+" is required, but not found.")
 	}
 	return nil
 }
 
-// Creates a virt-copy-out command that recursively copies a directory from the VM's
-// filesystem (vmDir) into a directory on the host (localDir).
-// Note: both directories must exist, otherwise the command will fail.
-func CopyFromVM(vmDiskFile, vmDir, localDir string) error {
-	cmd := exec.Command(virtcopyoutBinary, "-a", vmDiskFile, vmDir, localDir)
+// Runs virt-tar-in which unarchive a local archive into a directory (vmDir) inside the VM disk.
+
+// Runs virt-copy-out which recursively extract a directory from the VM's
+// filesystem (vmDir) into a tar archive.
+func CopyFromVM(vmDiskFile, vmDir, tarFile string) error {
+	cmd := exec.Command(virtTarOutBinary, "-a", vmDiskFile, vmDir, tarFile)
 	stdoutStderr, err := cmd.CombinedOutput()
 	if err != nil {
 		output := fmt.Sprintf("[%s]", stdoutStderr)

src/router/routerVMs.go

@@ -9,7 +9,6 @@ import (
 	"nexus-server/caps"	
 	"nexus-server/users"
 	"nexus-server/paths"
-	"nexus-server/utils"
 	"github.com/google/uuid"
 	"github.com/labstack/echo/v4"
 	"github.com/go-playground/validator/v10"
@@ -445,32 +444,16 @@ func (r *RouterVMs)ExportVMDir(c echo.Context) error {
 			return echo.NewHTTPError(http.StatusBadRequest, err.Error())
 		}
 
-		// Creates a unique temporary directory in which the VM's dir will be recursively copied.
+		// Creates a unique tar filename.
 		tmpDir := paths.GetInstance().TmpDir
-		uniqTmpDir := filepath.Join(tmpDir, "exportdir_"+vm.ID.String())
-		if err := os.Mkdir(uniqTmpDir, 0750); err != nil {
-			log.Error("Failed creating tmp dir for VM dir copy: "+err.Error())
-			return echo.NewHTTPError(http.StatusInternalServerError, "Failed creating tmp dir for VM dir copy")
-		}
-		defer func(dir string) {
-			if err := os.RemoveAll(dir); err != nil {
-				log.Error("Failed removing tmp dir for VM dir copy: "+err.Error())
-			}
-		}(uniqTmpDir)
-
-		// Extracts VM's p.Dir directory inside uniqTmpDir directory on the host.
-		if err := r.vms.ExportVMFiles(vm, p.Dir, uniqTmpDir); err != nil {
-			return echo.NewHTTPError(http.StatusBadRequest, "Failed reading VM's dir")
-		}
-	
-		// Creates a tar archive from the extracted VM directory.
 		tarFile := filepath.Join(tmpDir, "exportdir_"+vm.ID.String()+".tar")
-		if err := utils.TarDir(uniqTmpDir, tarFile); err != nil {
-			log.Error("Failed creating archive \""+tarFile+"\": "+err.Error())
-			return echo.NewHTTPError(http.StatusInternalServerError, "Failed creating VM's dir archive")
+
+		// Extracts VM's p.Dir directory into tarFile on the host.
+		if err := r.vms.ExportVMFiles(vm, p.Dir, tarFile); err != nil {
+			return echo.NewHTTPError(http.StatusBadRequest, "Failed extracting VM's dir")
 		}
 	
-		// Sends the archive back to the client and once done, deletes it.
+		// Sends the archive back to the client and once completed, deletes it.
 		defer func(file string) {
 			if err := os.Remove(file); err != nil {
 				log.Error("Failed removing archive of extracted VM dir: "+err.Error())
@@ -489,7 +472,6 @@ func (r *RouterVMs)ImportFilesToVM(c echo.Context) error {
 	return r.performVMAction(c, caps.CAP_VM_WRITEFS_ANY, caps.CAP_VM_WRITEFS, func(c echo.Context, vm *vms.VM) error {
 		// Retrieves the various client arguments.
 		vmDir := c.FormValue("vmDir")
-		localDir := c.FormValue("localDir")
 
 		// Retrieves the tar archive (uploadedTarFile).
 		tarFile, err := c.FormFile("file")
@@ -521,24 +503,9 @@ func (r *RouterVMs)ImportFilesToVM(c echo.Context) error {
 			return echo.NewHTTPError(http.StatusInternalServerError, err.Error())
 		}
 
-		// Extracts the archive into tmpExtractDir.
-		tmpExtractDir := filepath.Join(tmpDir, "upload_"+uuid.String())
-		if err := os.Mkdir(tmpExtractDir, 0750); err != nil {
-			msg := "ImportFilesToVM: failed creating dir: "+err.Error()
-			log.Error(msg)
-			return echo.NewHTTPError(http.StatusInternalServerError, msg)
-		}
-		defer os.RemoveAll(tmpExtractDir)
-
-		if err := utils.Untar(uploadedTarFile, tmpExtractDir); err != nil {
-			msg := "ImportFilesToVM: failed unarchiving tarball: "+err.Error()
-			log.Error(msg)
-			return echo.NewHTTPError(http.StatusInternalServerError, msg)
-		}
-		
 		// Copy the archive's files into the VM
 		// IMPORTANT: check the VM is NOT running!
-		if err = r.vms.ImportFilesToVM(vm, filepath.Join(tmpExtractDir, localDir), vmDir); err != nil {
+		if err = r.vms.ImportFilesToVM(vm, uploadedTarFile, vmDir); err != nil {
 			return echo.NewHTTPError(http.StatusBadRequest, err.Error())
 		}
 	

src/vms/vms.go

@@ -364,10 +364,10 @@ func (vms *VMs)DeleteVMAccess(vmID uuid.UUID, loggedUserEmail, userEmail string)
 	return nil
 }
 
-// Exports a VM's directory and its subdirectories into the specified directory on the host.
-func (vms *VMs)ExportVMFiles(vm *VM, vmDir, hostDir string) error {
+// Exports a VM's directory and its subdirectories into a tar archive on the host.
+func (vms *VMs)ExportVMFiles(vm *VM, vmDir, tarFile string) error {
 	vmDisk := vm.getDiskPath()
-	return exec.CopyFromVM(vmDisk, vmDir, hostDir)
+	return exec.CopyFromVM(vmDisk, vmDir, tarFile)
 }
 
 // Import files into a VM's filesystem, in a specified directory.