restic/snapshot.go
Alexander Neumann 5cdcc99eba Use array instead of hash for backend.ID
Since backend.ID is always a slice of constant length, use an array
instead of a slice. Mostly, arrays behave as slices, except that an
array cannot be nil, so use `*backend.ID` insteaf of `backend.ID` in
places where the absence of an ID is possible (e.g. for the Subtree of a
Node, which may not present when the node is a file node).

This change allows to directly use backend.ID as the the key for a map,
so that arbitrary data structures (e.g. a Set implemented as a
map[backend.ID]struct{}) can easily be formed.
2015-07-25 18:01:57 +02:00

104 lines
2.1 KiB
Go

package restic
import (
"fmt"
"os"
"os/user"
"path/filepath"
"strconv"
"time"
"github.com/restic/restic/backend"
"github.com/restic/restic/repository"
)
type Snapshot struct {
Time time.Time `json:"time"`
Parent *backend.ID `json:"parent,omitempty"`
Tree *backend.ID `json:"tree"`
Paths []string `json:"paths"`
Hostname string `json:"hostname,omitempty"`
Username string `json:"username,omitempty"`
UID uint32 `json:"uid,omitempty"`
GID uint32 `json:"gid,omitempty"`
Excludes []string `json:"excludes,omitempty"`
id *backend.ID // plaintext ID, used during restore
}
func NewSnapshot(paths []string) (*Snapshot, error) {
for i, path := range paths {
if p, err := filepath.Abs(path); err != nil {
paths[i] = p
}
}
sn := &Snapshot{
Paths: paths,
Time: time.Now(),
}
hn, err := os.Hostname()
if err == nil {
sn.Hostname = hn
}
err = sn.fillUserInfo()
if err != nil {
return nil, err
}
return sn, nil
}
func LoadSnapshot(repo *repository.Repository, id backend.ID) (*Snapshot, error) {
sn := &Snapshot{id: &id}
err := repo.LoadJSONUnpacked(backend.Snapshot, id, sn)
if err != nil {
return nil, err
}
return sn, nil
}
func (sn Snapshot) String() string {
return fmt.Sprintf("<Snapshot of %v at %s>", sn.Paths, sn.Time)
}
func (sn Snapshot) ID() *backend.ID {
return sn.id
}
func (sn *Snapshot) fillUserInfo() error {
usr, err := user.Current()
if err != nil {
return nil
}
sn.Username = usr.Username
uid, err := strconv.ParseInt(usr.Uid, 10, 32)
if err != nil {
return err
}
sn.UID = uint32(uid)
gid, err := strconv.ParseInt(usr.Gid, 10, 32)
if err != nil {
return err
}
sn.GID = uint32(gid)
return nil
}
// FindSnapshot takes a string and tries to find a snapshot whose ID matches
// the string as closely as possible.
func FindSnapshot(repo *repository.Repository, s string) (backend.ID, error) {
// find snapshot id with prefix
name, err := backend.Find(repo.Backend(), backend.Snapshot, s)
if err != nil {
return backend.ID{}, err
}
return backend.ParseID(name)
}