Rollback to aufs and cleanup overlay2 in case of missing config.v2.json

Add test for missing config.v2.json

Changelog-entry: Rollback to aufs and cleanup overlay2 in case of missing config.v2.json
Change-type: patch
Signed-off-by: zoobot <rommims@gmail.com>

pkg/storagemigration/failcleanup.go

@@ -10,7 +10,6 @@ import (
 // FailCleanup should be run after a failed migration.
 // It will remove any files left over from the migration process
 // and migrate containers back to aufs.
-//
 func failCleanup(root string) error {
 	logrus.WithField("storage_root", root).Warning("recovering from failed aufs to overlay migration")
 

pkg/storagemigration/migrate.go

@@ -128,7 +128,6 @@ func Migrate(root string) (err error) {
 	if err != nil {
 		return fmt.Errorf("Error migrating containers to overlay2: %v", err)
 	}
-
 	return nil
 }
 
@@ -340,7 +339,10 @@ func SwitchAllContainersStorageDriver(root, newStorageDriver string) error {
 		case nil:
 			logrus.WithField("container_id", containerID).Debugf("reconfigured storage-driver to %s", newStorageDriver)
 		case errNoConfigV2JSON:
-			logrus.WithField("container_id", containerID).Warning("ignoring container without config.v2.json")
+			if newStorageDriver == "overlay2" {
+				return fmt.Errorf("Error containerID %s: %v", containerID, err)
+			}
+			logrus.WithField("container_id", containerID).Errorf("has no config.v2.json %s", newStorageDriver)
 		default:
 			return fmt.Errorf("Error rewriting container config for %s: %v", containerID, err)
 		}

pkg/storagemigration/migrate_test.go

@@ -41,6 +41,7 @@ func setup(t *testing.T) (*fs.Dir, *State, func()) {
 			),
 		),
 	)
+
 	state := &State{
 		Layers: []Layer{
 			{
@@ -132,3 +133,37 @@ func TestFailCleanup(t *testing.T) {
 	_, err = os.Stat(root.Join("aufs"))
 	assert.NilError(t, err)
 }
+
+func TestFailCleanupContainer(t *testing.T) {
+	root, _, cleanup := setup(t)
+	defer cleanup()
+
+	// delete config.v2.json to force SwitchAllContainersStorageDriver to fail
+	os.Remove(root.Join("containers", "bebe92422caf828ab21ae39974a0c003a29970ec09c6e5529bbb24f71eb9ca2ef", "config.v2.json"))
+
+	err := Migrate(root.Path())
+	if err == nil {
+		// won't err on rollback to aufs fail
+		assert.NilError(t, err)
+	} else {
+		// only errs on migration to overlay2 fail
+		assert.ErrorContains(t, err, "bebe92422caf828ab21ae39974a0c003a29970ec09c6e5529bbb24f71eb9ca2ef")
+
+		// // config.v2.json should not exists
+		_, err = os.Stat(root.Join("containers", "bebe92422caf828ab21ae39974a0c003a29970ec09c6e5529bbb24f71eb9ca2ef", "config.v2.json"))
+		assert.ErrorType(t, err, os.IsNotExist)
+
+		// migration logfile should exists
+		_, err = os.Stat(root.Join("migrate.log"))
+		assert.NilError(t, err)
+
+		// overlay2 directory should not exists
+		_, err = os.Stat(root.Join("overlay2"))
+		println("err", root.Join("overlay2"), err)
+		assert.ErrorType(t, err, os.IsNotExist)
+
+		// aufs directory should still exists
+		_, err = os.Stat(root.Join("aufs"))
+		assert.NilError(t, err)
+	}
+}