package migrations import ( "context" "fmt" "os" "path" "github.com/restic/restic/internal/backend" "github.com/restic/restic/internal/backend/s3" "github.com/restic/restic/internal/cache" "github.com/restic/restic/internal/debug" "github.com/restic/restic/internal/errors" "github.com/restic/restic/internal/restic" ) func init() { register(&S3Layout{}) } // S3Layout migrates a repository on an S3 backend from the "s3legacy" to the // "default" layout. type S3Layout struct{} func toS3Backend(repo restic.Repository) *s3.Backend { b := repo.Backend() // unwrap cache if be, ok := b.(*cache.Backend); ok { b = be.Backend } be, ok := b.(*s3.Backend) if !ok { debug.Log("backend is not s3") return nil } return be } // Check tests whether the migration can be applied. func (m *S3Layout) Check(ctx context.Context, repo restic.Repository) (bool, string, error) { be := toS3Backend(repo) if be == nil { debug.Log("backend is not s3") return false, "backend is not s3", nil } if be.Layout.Name() != "s3legacy" { debug.Log("layout is not s3legacy") return false, "not using the legacy s3 layout", nil } return true, "", nil } func (m *S3Layout) RepoCheck() bool { return false } func retry(max int, fail func(err error), f func() error) error { var err error for i := 0; i < max; i++ { err = f() if err == nil { return nil } if fail != nil { fail(err) } } return err } // maxErrors for retrying renames on s3. const maxErrors = 20 func (m *S3Layout) moveFiles(ctx context.Context, be *s3.Backend, l backend.Layout, t restic.FileType) error { printErr := func(err error) { fmt.Fprintf(os.Stderr, "renaming file returned error: %v\n", err) } return be.List(ctx, t, func(fi restic.FileInfo) error { h := restic.Handle{Type: t, Name: fi.Name} debug.Log("move %v", h) return retry(maxErrors, printErr, func() error { return be.Rename(ctx, h, l) }) }) } // Apply runs the migration. func (m *S3Layout) Apply(ctx context.Context, repo restic.Repository) error { be := toS3Backend(repo) if be == nil { debug.Log("backend is not s3") return errors.New("backend is not s3") } oldLayout := &backend.S3LegacyLayout{ Path: be.Path(), Join: path.Join, } newLayout := &backend.DefaultLayout{ Path: be.Path(), Join: path.Join, } be.Layout = oldLayout for _, t := range []restic.FileType{ restic.SnapshotFile, restic.PackFile, restic.KeyFile, restic.LockFile, } { err := m.moveFiles(ctx, be, newLayout, t) if err != nil { return err } } be.Layout = newLayout return nil } // Name returns the name for this migration. func (m *S3Layout) Name() string { return "s3_layout" } // Desc returns a short description what the migration does. func (m *S3Layout) Desc() string { return "move files from 's3legacy' to the 'default' repository layout" }