restic/internal/server/rofs/snapshots_dir.go
Alexander Neumann 9da6e7c329 wip
2024-04-07 09:58:44 +02:00

148 lines
3 KiB
Go

package rofs
import (
"context"
"io"
"io/fs"
"time"
"github.com/restic/restic/internal/debug"
"github.com/restic/restic/internal/restic"
)
// SnapshotsDir implements a tree of snapshots in repo as a file system in various sub-directories.
type SnapshotsDir struct {
lastUpdate time.Time
pathTemplates []string
timeTemplate string
// list of top-level directories
entries []rofsEntry
repo restic.Repository
}
// ensure that the interface is implemented
var _ rofsEntry = &SnapshotsDir{}
// NewSnapshotsDir initializes a new top-level snapshots directory.
func NewSnapshotsDir(ctx context.Context, repo restic.Repository, pathTemplates []string, timeTemplate string) *SnapshotsDir {
dir := &SnapshotsDir{
pathTemplates: pathTemplates,
timeTemplate: timeTemplate,
lastUpdate: time.Now(),
repo: repo,
}
// testnames := []string{"foo", "bar", "baz", "snapshots"}
// for _, name := range testnames {
// dir.entries = append(dir.entries,
// fs.FileInfoToDirEntry(FileInfo{
// name: name,
// mode: 0644,
// modtime: time.Now(),
// }))
// }
// slices.SortFunc(dir.entries, func(a, b fs.DirEntry) int {
// if a.Name() == b.Name() {
// return 0
// }
// if a.Name() < b.Name() {
// return 1
// }
// return -1
// })
// // prepare for readdir with positive n
// dir.entriesRemaining = dir.entries
return dir
}
// ensure that it implements all necessary interfaces.
var _ fs.ReadDirFile = &SnapshotsDir{}
// Close closes the snapshots dir.
func (dir *SnapshotsDir) Close() error {
debug.Log("Close()")
// reset readdir list
// dir.entriesRemaining = dir.entries
return nil
}
// Read is not implemented for a dir.
func (dir *SnapshotsDir) Read([]byte) (int, error) {
return 0, &fs.PathError{
Op: "read",
Err: fs.ErrInvalid,
}
}
// Stat returns information about the dir.
func (dir *SnapshotsDir) Stat() (fs.FileInfo, error) {
debug.Log("Stat(root)")
fi := FileInfo{
name: "root", // use special name, this is the root node
size: 0,
modtime: dir.lastUpdate,
mode: 0755,
}
return fi, nil
}
// ReadDir returns a list of entries.
func (dir *SnapshotsDir) ReadDir(n int) ([]fs.DirEntry, error) {
if n < 0 {
debug.Log("Readdir(root, %v), return %v entries", n, len(dir.entries))
return dir.entries, nil
}
// complicated pointer handling
if n > len(dir.entriesRemaining) {
n = len(dir.entriesRemaining)
}
if n == 0 {
return nil, io.EOF
}
list := dir.entriesRemaining[:n]
dir.entriesRemaining = dir.entriesRemaining[n:]
return list, nil
}
// DirEntry returns meta data about the dir snapshots dir itself.
func (dir *SnapshotsDir) DirEntry() fs.DirEntry {
return dirEntry{
fileInfo: FileInfo{
name: "snapshots",
mode: fs.ModeDir | 0755,
modtime: dir.lastUpdate,
},
}
}
// Open opens the dir for reading.
func (dir *SnapshotsDir) Open() (fs.File, error) {
d := &openDir{
path: "snapshots",
fileInfo: FileInfo{
name: "snapshots",
mode: fs.ModeDir | 0555,
modtime: dir.lastUpdate,
},
entries: dirMap2DirEntry(dir.entries),
}
return d
}