restic/snapshot.go

116 lines
1.9 KiB
Go

package khepri
import (
"encoding/json"
"fmt"
"os"
"os/user"
"time"
)
type Snapshot struct {
Time time.Time `json:"time"`
Content ID `json:"content"`
Tree *Tree `json:"-"`
Dir string `json:"dir"`
Hostname string `json:"hostname,omitempty"`
Username string `json:"username,omitempty"`
UID string `json:"uid,omitempty"`
GID string `json:"gid,omitempty"`
id ID `json:omit`
repo *Repository
}
func NewSnapshot(dir string) *Snapshot {
sn := &Snapshot{
Dir: dir,
Time: time.Now(),
}
hn, err := os.Hostname()
if err == nil {
sn.Hostname = hn
}
usr, err := user.Current()
if err == nil {
sn.Username = usr.Username
sn.UID = usr.Uid
sn.GID = usr.Gid
}
return sn
}
func (sn *Snapshot) Save(repo *Repository) (ID, error) {
if sn.Content == nil {
panic("Snapshot.Save() called with nil tree id")
}
obj, id_ch, err := repo.Create(TYPE_REF)
if err != nil {
return nil, err
}
enc := json.NewEncoder(obj)
err = enc.Encode(sn)
if err != nil {
return nil, err
}
err = obj.Close()
if err != nil {
return nil, err
}
sn.id = <-id_ch
return sn.id, nil
}
func LoadSnapshot(repo *Repository, id ID) (*Snapshot, error) {
rd, err := repo.Get(TYPE_REF, id)
if err != nil {
return nil, err
}
// TODO: maybe inject a hashing reader here and test if the given id is correct
dec := json.NewDecoder(rd)
sn := &Snapshot{}
err = dec.Decode(sn)
if err != nil {
return nil, err
}
sn.id = id
sn.repo = repo
return sn, nil
}
func (sn *Snapshot) RestoreAt(path string) error {
err := os.MkdirAll(path, 0700)
if err != nil {
return err
}
if sn.Tree == nil {
sn.Tree, err = NewTreeFromRepo(sn.repo, sn.Content)
if err != nil {
return err
}
}
return sn.Tree.CreateAt(path)
}
func (sn *Snapshot) ID() ID {
return sn.id
}
func (sn *Snapshot) String() string {
return fmt.Sprintf("<Snapshot of %q at %s>", sn.Dir, sn.Time.Format(time.RFC822Z))
}