Fix binary backup of mongodb 4.2

internal/databases/mongo/binary/mongod.go

@@ -127,7 +127,7 @@ func (mongodService *MongodService) GetBackupCursorExtended(backupCursorMeta *Ba
 	})
 }
 
-func (mongodService *MongodService) FixSystemDataAfterRestore(LastWriteTS primitive.Timestamp) error {
+func (mongodService *MongodService) FixSystemDataAfterRestore(LastWriteTS primitive.Timestamp, fixOplog bool) error {
 	ctx := mongodService.Context
 	localDatabase := mongodService.MongoClient.Database("local")
 
@@ -145,14 +145,18 @@ func (mongodService *MongodService) FixSystemDataAfterRestore(LastWriteTS primit
 		return err
 	}
 
-	tracelog.DebugLogger.Printf("oplogTruncateAfterPoint: %v", LastWriteTS)
-	err = replaceData(ctx, localDatabase.Collection("replset.oplogTruncateAfterPoint"), true,
-		bson.M{
-			"_id":                     "oplogTruncateAfterPoint",
-			"oplogTruncateAfterPoint": LastWriteTS,
-		})
-	if err != nil {
-		return err
+	if fixOplog {
+		tracelog.DebugLogger.Printf("oplogTruncateAfterPoint: %v", LastWriteTS)
+		err = replaceData(ctx, localDatabase.Collection("replset.oplogTruncateAfterPoint"), true,
+			bson.M{
+				"_id":                     "oplogTruncateAfterPoint",
+				"oplogTruncateAfterPoint": LastWriteTS,
+			})
+		if err != nil {
+			return err
+		}
+	} else {
+		tracelog.InfoLogger.Printf("We are skipping fix replset.oplogTruncateAfterPoint because it is disabled")
 	}
 
 	err = replaceData(ctx, localDatabase.Collection("system.replset"), false, nil)

internal/databases/mongo/binary/restore.go

@@ -55,20 +55,29 @@ func (restoreService *RestoreService) DoRestore(backupName, restoreMongodVersion
 		return err
 	}
 
-	err = restoreService.fixSystemData(sentinel)
-	if err != nil {
+	needFixOplog := NeedFixOplog(restoreMongodVersion)
+
+	if err = restoreService.fixSystemData(sentinel, needFixOplog); err != nil {
 		return err
 	}
 
-	return restoreService.recoverFromOplogAsStandalone()
+	if needFixOplog {
+		if err = restoreService.recoverFromOplogAsStandalone(); err != nil {
+			return err
+		}
+	} else {
+		tracelog.InfoLogger.Printf("We are skipping recoverFromOplogAsStandalone because it is disabled")
+	}
+
+	return nil
 }
 
 func (restoreService *RestoreService) downloadFromTarArchives(backupName string) error {
 	downloader := CreateConcurrentDownloader(restoreService.Uploader)
 	return downloader.Download(backupName, restoreService.LocalStorage.MongodDBPath)
 }
 
-func (restoreService *RestoreService) fixSystemData(sentinel *models.Backup) error {
+func (restoreService *RestoreService) fixSystemData(sentinel *models.Backup, needFixOplog bool) error {
 	mongodProcess, err := StartMongodWithDisableLogicalSessionCacheRefresh(restoreService.minimalConfigPath)
 	if err != nil {
 		return errors.Wrap(err, "unable to start mongod in special mode")
@@ -80,7 +89,7 @@ func (restoreService *RestoreService) fixSystemData(sentinel *models.Backup) err
 	}
 
 	lastWriteTS := sentinel.MongoMeta.BackupLastTS
-	err = mongodService.FixSystemDataAfterRestore(lastWriteTS)
+	err = mongodService.FixSystemDataAfterRestore(lastWriteTS, needFixOplog)
 	if err != nil {
 		return err
 	}

internal/databases/mongo/binary/utilities.go

@@ -6,6 +6,8 @@ import (
 	"golang.org/x/mod/semver"
 )
 
+const minOplogRecoverSupportedVersion = "4.2"
+
 // MajorMinorVersion return version in format '<MajorVersion>.<MinorVersion>' (without patch, prerelease, build, ...)
 func MajorMinorVersion(version string) string {
 	if len(version) == 0 {
@@ -29,3 +31,7 @@ func EnsureCompatibilityToRestoreMongodVersions(backupMongodVersion, restoreMong
 	}
 	return nil
 }
+
+func NeedFixOplog(mongodVersion string) bool {
+	return semver.Compare(MajorMinorVersion(mongodVersion), MajorMinorVersion(minOplogRecoverSupportedVersion)) > 0
+}

internal/databases/mongo/binary/utilities_test.go

@@ -0,0 +1,15 @@
+package binary
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNeedFixOplog(t *testing.T) {
+	assert.False(t, NeedFixOplog("4.0"))
+	assert.False(t, NeedFixOplog("4.2"))
+	assert.True(t, NeedFixOplog("4.4"))
+	assert.True(t, NeedFixOplog("5.0"))
+	assert.True(t, NeedFixOplog("6.0"))
+}