🧹 improve error handling for gcp snapshot

motor/providers/gcpinstancesnapshot/provider.go

@@ -183,12 +183,6 @@ func New(pCfg *providers.Config) (*Provider, error) {
 		return nil, errors.New("invalid target type")
 	}
 
-	// attach created disk to the scanner instance
-	err = sc.attachDisk(scanner.projectID, scanner.zone, scanner.instanceName, mi.diskUrl, mi.deviceName)
-	if err != nil {
-		return nil, err
-	}
-
 	errorHandler := func() {
 		// use different err variable to ensure it does not overshadow the real error
 		dErr := sc.detachDisk(scanner.projectID, scanner.zone, scanner.instanceName, mi.deviceName)
@@ -202,6 +196,14 @@ func New(pCfg *providers.Config) (*Provider, error) {
 		}
 	}
 
+	// attach created disk to the scanner instance
+	log.Debug().Str("device-name", mi.deviceName).Msg("attach created disk to the scanner instance")
+	err = sc.attachDisk(scanner.projectID, scanner.zone, scanner.instanceName, mi.diskUrl, mi.deviceName)
+	if err != nil {
+		errorHandler()
+		return nil, err
+	}
+
 	// mount volume
 	shell := []string{"sh", "-c"}
 	volumeMounter := snapshot.NewVolumeMounter(shell)

motor/providers/gcpinstancesnapshot/snapshot.go

@@ -2,6 +2,7 @@ package gcpinstancesnapshot
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -203,7 +204,8 @@ func (sc *SnapshotCreator) createDisk(disk *compute.Disk, projectID, zone, diskN
 		}
 		if operation.Status == "DONE" {
 			if operation.Error != nil {
-				return clonedDiskUrl, fmt.Errorf("operation failed: %+v", operation.Error.Errors)
+				data, _ := json.Marshal(operation.Error.Errors)
+				return clonedDiskUrl, fmt.Errorf("could not create disk: " + string(data))
 			}
 			clonedDiskUrl = operation.TargetLink
 			break
@@ -235,7 +237,7 @@ func (sc *SnapshotCreator) cloneDisk(sourceDisk, projectID, zone, diskName strin
 	return sc.createDisk(disk, projectID, zone, diskName)
 }
 
-// attachDisk attaches a disk to an instanc
+// attachDisk attaches a disk to an instance
 func (sc *SnapshotCreator) attachDisk(projectID, zone, instanceName, sourceDiskUrl, deviceName string) error {
 	ctx := context.Background()
 
@@ -253,18 +255,21 @@ func (sc *SnapshotCreator) attachDisk(projectID, zone, instanceName, sourceDiskU
 	// attach the disk to the instance
 	op, err := computeService.Instances.AttachDisk(projectID, zone, instanceName, attachedDisk).Context(ctx).Do()
 	if err != nil {
+		log.Debug().Err(err).Str("device-name", deviceName).Msg("could not attach disk")
 		return err
 	}
 
 	// wait for the operation to complete
 	for {
 		operation, err := computeService.ZoneOperations.Get(projectID, zone, op.Name).Context(ctx).Do()
 		if err != nil {
+			log.Debug().Err(err).Str("device-name", deviceName).Msg("could not find operation for disk attachment")
 			return err
 		}
 		if operation.Status == "DONE" {
 			if operation.Error != nil {
-				return fmt.Errorf("operation failed: %+v", operation.Error.Errors)
+				data, _ := json.Marshal(operation.Error.Errors)
+				return fmt.Errorf("disk attachment failed: " + string(data))
 			}
 			break
 		}