restic/internal/repository/upgrade_repo.go

104 lines
2.8 KiB
Go

package repository
import (
"context"
"fmt"
"os"
"path/filepath"
"github.com/restic/restic/internal/backend"
"github.com/restic/restic/internal/restic"
)
type upgradeRepoV2Error struct {
UploadNewConfigError error
ReuploadOldConfigError error
BackupFilePath string
}
func (err *upgradeRepoV2Error) Error() string {
if err.ReuploadOldConfigError != nil {
return fmt.Sprintf("error uploading config (%v), re-uploading old config filed failed as well (%v), but there is a backup of the config file in %v", err.UploadNewConfigError, err.ReuploadOldConfigError, err.BackupFilePath)
}
return fmt.Sprintf("error uploading config (%v), re-uploaded old config was successful, there is a backup of the config file in %v", err.UploadNewConfigError, err.BackupFilePath)
}
func (err *upgradeRepoV2Error) Unwrap() error {
// consider the original upload error as the primary cause
return err.UploadNewConfigError
}
func upgradeRepository(ctx context.Context, repo *Repository) error {
h := backend.Handle{Type: backend.ConfigFile}
if !repo.be.HasAtomicReplace() {
// remove the original file for backends which do not support atomic overwriting
err := repo.be.Remove(ctx, h)
if err != nil {
return fmt.Errorf("remove config failed: %w", err)
}
}
// upgrade config
cfg := repo.Config()
cfg.Version = 2
err := restic.SaveConfig(ctx, repo, cfg)
if err != nil {
return fmt.Errorf("save new config file failed: %w", err)
}
return nil
}
func UpgradeRepo(ctx context.Context, repo *Repository) error {
if repo.Config().Version != 1 {
return fmt.Errorf("repository has version %v, only upgrades from version 1 are supported", repo.Config().Version)
}
tempdir, err := os.MkdirTemp("", "restic-migrate-upgrade-repo-v2-")
if err != nil {
return fmt.Errorf("create temp dir failed: %w", err)
}
h := backend.Handle{Type: restic.ConfigFile}
// read raw config file and save it to a temp dir, just in case
rawConfigFile, err := repo.LoadRaw(ctx, restic.ConfigFile, restic.ID{})
if err != nil {
return fmt.Errorf("load config file failed: %w", err)
}
backupFileName := filepath.Join(tempdir, "config")
err = os.WriteFile(backupFileName, rawConfigFile, 0600)
if err != nil {
return fmt.Errorf("write config file backup to %v failed: %w", tempdir, err)
}
// run the upgrade
err = upgradeRepository(ctx, repo)
if err != nil {
// build an error we can return to the caller
repoError := &upgradeRepoV2Error{
UploadNewConfigError: err,
BackupFilePath: backupFileName,
}
// try contingency methods, reupload the original file
_ = repo.Backend().Remove(ctx, h)
err = repo.Backend().Save(ctx, h, backend.NewByteReader(rawConfigFile, nil))
if err != nil {
repoError.ReuploadOldConfigError = err
}
return repoError
}
_ = os.Remove(backupFileName)
_ = os.Remove(tempdir)
return nil
}