backend structure build

backend/internal/services/iscsi/lun.go

@@ -0,0 +1,99 @@
+package iscsi
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// AddLUN adds a LUN to a target
+func (s *Service) AddLUN(targetID string, lunNumber int, devicePath string, lunType string) error {
+	s.logger.Info("Adding LUN to target", "target", targetID, "lun", lunNumber, "device", devicePath, "type", lunType)
+
+	// Validate device exists
+	if _, err := os.Stat(devicePath); err != nil {
+		return fmt.Errorf("device not found: %s", devicePath)
+	}
+
+	// Validate LUN type
+	if lunType != "disk" && lunType != "tape" {
+		return fmt.Errorf("invalid LUN type: %s (must be 'disk' or 'tape')", lunType)
+	}
+
+	// For tape library:
+	// LUN 0 = Media changer
+	// LUN 1-8 = Tape drives
+	if lunType == "tape" {
+		if lunNumber == 0 {
+			// Media changer
+			devicePath = "/dev/sg0" // Default media changer
+		} else if lunNumber >= 1 && lunNumber <= 8 {
+			// Tape drive
+			devicePath = fmt.Sprintf("/dev/nst%d", lunNumber-1)
+		} else {
+			return fmt.Errorf("invalid LUN number for tape: %d (must be 0-8)", lunNumber)
+		}
+	}
+
+	// Update target configuration
+	target, err := s.GetTarget(targetID)
+	if err != nil {
+		return err
+	}
+
+	// Check if LUN already exists
+	for _, lun := range target.LUNs {
+		if lun.Number == lunNumber {
+			return fmt.Errorf("LUN %d already exists", lunNumber)
+		}
+	}
+
+	// Add LUN
+	target.LUNs = append(target.LUNs, LUN{
+		Number: lunNumber,
+		Device: devicePath,
+		Type:   lunType,
+	})
+
+	// Write updated config
+	return s.writeSCSTConfig(target)
+}
+
+// RemoveLUN removes a LUN from a target
+func (s *Service) RemoveLUN(targetID string, lunNumber int) error {
+	s.logger.Info("Removing LUN from target", "target", targetID, "lun", lunNumber)
+
+	target, err := s.GetTarget(targetID)
+	if err != nil {
+		return err
+	}
+
+	// Find and remove LUN
+	found := false
+	newLUNs := []LUN{}
+	for _, lun := range target.LUNs {
+		if lun.Number != lunNumber {
+			newLUNs = append(newLUNs, lun)
+		} else {
+			found = true
+		}
+	}
+
+	if !found {
+		return fmt.Errorf("LUN %d not found", lunNumber)
+	}
+
+	target.LUNs = newLUNs
+	return s.writeSCSTConfig(target)
+}
+
+// MapRepositoryToLUN maps a disk repository to an iSCSI LUN
+func (s *Service) MapRepositoryToLUN(targetID string, repositoryPath string, lunNumber int) error {
+	// Resolve repository path to device
+	devicePath, err := filepath.EvalSymlinks(repositoryPath)
+	if err != nil {
+		return fmt.Errorf("failed to resolve repository path: %w", err)
+	}
+
+	return s.AddLUN(targetID, lunNumber, devicePath, "disk")
+}