restorer

Documentation

Overview

Package restorer contains code to restore data from a repository.

The Restorer tries to keep the number of backend requests minimal. It does this by downloading all required blobs of a pack file with a single backend request and avoiding repeated downloads of the same pack. In addition, several pack files are fetched concurrently.

Here is high-level pseudo-code of how the Restorer attempts to achieve these goals:

while there are packs to process
  choose a pack to process                      [1]
  retrieve the pack from the backend            [2]
  write pack blobs to the files that need them  [3]

Retrieval of repository packs (step [2]) and writing target files (step [3]) are performed concurrently on multiple goroutines.

Implementation does not guarantee order in which blobs are written to the target files and, for example, the last blob of a file can be written to the file before any of the preceding file blobs. It is therefore possible to have gaps in the data written to the target files if restore fails or interrupted by the user.

Index

• type Restorer
  • func NewRestorer(ctx context.Context, repo restic.Repository, id restic.ID) (*Restorer, error)
  • func (res *Restorer) RestoreTo(ctx context.Context, dst string) error
  • func (res *Restorer) Snapshot() *restic.Snapshot
  • func (res *Restorer) VerifyFiles(ctx context.Context, dst string) (int, error)

Types

type Restorer

type Restorer struct {
	Error        func(location string, err error) error
	SelectFilter func(item string, dstpath string, node *restic.Node) (selectedForRestore bool, childMayBeSelected bool)
	// contains filtered or unexported fields
}

Restorer is used to restore a snapshot to a directory.

func NewRestorer

func NewRestorer(ctx context.Context, repo restic.Repository, id restic.ID) (*Restorer, error)

NewRestorer creates a restorer preloaded with the content from the snapshot id.

func (*Restorer) RestoreTo

func (res *Restorer) RestoreTo(ctx context.Context, dst string) error

RestoreTo creates the directories and files in the snapshot below dst. Before an item is created, res.Filter is called.

func (*Restorer) Snapshot

func (res *Restorer) Snapshot() *restic.Snapshot

Snapshot returns the snapshot this restorer is configured to use.

func (*Restorer) VerifyFiles

func (res *Restorer) VerifyFiles(ctx context.Context, dst string) (int, error)

VerifyFiles checks whether all regular files in the snapshot res.sn have been successfully written to dst. It stops when it encounters an error. It returns that error and the number of files it has successfully verified.