docker-volume-backup/internal/storage/webdav/webdav.go

122 lines
3.6 KiB
Go

// Copyright 2022 - Offen Authors <hioffen@posteo.de>
// SPDX-License-Identifier: MPL-2.0
package webdav
import (
"errors"
"fmt"
"io/fs"
"net/http"
"os"
"path"
"path/filepath"
"strings"
"time"
"github.com/offen/docker-volume-backup/internal/storage"
"github.com/studio-b12/gowebdav"
)
type webDavStorage struct {
*storage.StorageBackend
client *gowebdav.Client
url string
}
// Config allows to configure a WebDAV storage backend.
type Config struct {
URL string
RemotePath string
Username string
Password string
URLInsecure bool
}
// NewStorageBackend creates and initializes a new WebDav storage backend.
func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
if opts.Username == "" || opts.Password == "" {
return nil, errors.New("NewStorageBackend: WEBDAV_URL is defined, but no credentials were provided")
} else {
webdavClient := gowebdav.NewClient(opts.URL, opts.Username, opts.Password)
if opts.URLInsecure {
defaultTransport, ok := http.DefaultTransport.(*http.Transport)
if !ok {
return nil, errors.New("NewStorageBackend: unexpected error when asserting type for http.DefaultTransport")
}
webdavTransport := defaultTransport.Clone()
webdavTransport.TLSClientConfig.InsecureSkipVerify = opts.URLInsecure
webdavClient.SetTransport(webdavTransport)
}
return &webDavStorage{
StorageBackend: &storage.StorageBackend{
DestinationPath: opts.RemotePath,
Log: logFunc,
},
client: webdavClient,
}, nil
}
}
// Name returns the name of the storage backend
func (b *webDavStorage) Name() string {
return "WebDAV"
}
// Copy copies the given file to the WebDav storage backend.
func (b *webDavStorage) Copy(file string) error {
bytes, err := os.ReadFile(file)
_, name := path.Split(file)
if err != nil {
return fmt.Errorf("(*webDavStorage).Copy: Error reading the file to be uploaded: %w", err)
}
if err := b.client.MkdirAll(b.DestinationPath, 0644); err != nil {
return fmt.Errorf("(*webDavStorage).Copy: Error creating directory '%s' on WebDAV server: %w", b.DestinationPath, err)
}
if err := b.client.Write(filepath.Join(b.DestinationPath, name), bytes, 0644); err != nil {
return fmt.Errorf("(*webDavStorage).Copy: Error uploading the file to WebDAV server: %w", err)
}
b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup '%s' to WebDAV URL '%s' at path '%s'.", file, b.url, b.DestinationPath)
return nil
}
// Prune rotates away backups according to the configuration and provided deadline for the WebDav storage backend.
func (b *webDavStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
candidates, err := b.client.ReadDir(b.DestinationPath)
if err != nil {
return nil, fmt.Errorf("(*webDavStorage).Prune: Error looking up candidates from remote storage: %w", err)
}
var matches []fs.FileInfo
var lenCandidates int
for _, candidate := range candidates {
if !strings.HasPrefix(candidate.Name(), pruningPrefix) {
continue
}
lenCandidates++
if candidate.ModTime().Before(deadline) {
matches = append(matches, candidate)
}
}
stats := &storage.PruneStats{
Total: uint(lenCandidates),
Pruned: uint(len(matches)),
}
if err := b.DoPrune(b.Name(), len(matches), lenCandidates, "WebDAV backup(s)", func() error {
for _, match := range matches {
if err := b.client.Remove(filepath.Join(b.DestinationPath, match.Name())); err != nil {
return fmt.Errorf("(*webDavStorage).Prune: Error removing file from WebDAV storage: %w", err)
}
}
return nil
}); err != nil {
return stats, err
}
return stats, nil
}