Initial commit: docker compose config

server/torrfs/webdav/webdav.go

@@ -0,0 +1,232 @@
+package webdav
+
+import (
+	"context"
+	"errors"
+	"io"
+	"io/fs"
+	"os"
+	"path"
+	"sync"
+	"time"
+
+	"server/log"
+
+	"server/torrfs"
+
+	"github.com/gin-gonic/gin"
+	"golang.org/x/net/webdav"
+)
+
+var missingMethods = []string{
+	"PROPFIND", "PROPPATCH", "MKCOL", "COPY", "MOVE", "LOCK", "UNLOCK",
+}
+
+func MountWebDAV(r *gin.Engine) {
+	log.TLogln("Starting WebDAV")
+	tfs := torrfs.AsFS(torrfs.New())
+
+	h := &webdav.Handler{
+		Prefix:     "/dav",
+		FileSystem: &ReadOnlyFS{FS: tfs},
+		LockSystem: webdav.NewMemLS(),
+	}
+
+	grp := r.Group("/dav")
+
+	handler := func(c *gin.Context) {
+		h.ServeHTTP(c.Writer, c.Request)
+	}
+
+	grp.Any("/*webdav", handler)
+	for _, m := range missingMethods {
+		grp.Handle(m, "/*webdav", handler)
+	}
+
+	grp.Any("", handler)
+	for _, m := range missingMethods {
+		grp.Handle(m, "", handler)
+	}
+}
+
+type ReadOnlyFS struct {
+	FS fs.FS
+}
+
+var _ webdav.FileSystem = (*ReadOnlyFS)(nil)
+
+func (ro *ReadOnlyFS) Mkdir(ctx context.Context, name string, perm os.FileMode) error {
+	return os.ErrPermission
+}
+
+func (ro *ReadOnlyFS) RemoveAll(ctx context.Context, name string) error {
+	return os.ErrPermission
+}
+
+func (ro *ReadOnlyFS) Rename(ctx context.Context, oldName, newName string) error {
+	return os.ErrPermission
+}
+
+func (ro *ReadOnlyFS) Stat(ctx context.Context, name string) (os.FileInfo, error) {
+	name = cleanWebDAVPath(name)
+	return fs.Stat(ro.FS, name)
+}
+
+func (ro *ReadOnlyFS) OpenFile(ctx context.Context, name string, flag int, perm os.FileMode) (webdav.File, error) {
+	if flag&(os.O_WRONLY|os.O_RDWR|os.O_APPEND|os.O_CREATE|os.O_TRUNC) != 0 {
+		return nil, os.ErrPermission
+	}
+
+	name = cleanWebDAVPath(name)
+
+	f, err := ro.FS.Open(name)
+	if err != nil {
+		return nil, err
+	}
+
+	return newROFile(ro.FS, name, f), nil
+}
+
+// --- file wrapper ---
+
+type roFile struct {
+	fsys fs.FS
+	name string
+
+	mu sync.Mutex
+	f  fs.File
+
+	dirPos  int
+	dirList []fs.DirEntry
+}
+
+func newROFile(fsys fs.FS, name string, f fs.File) *roFile {
+	return &roFile{fsys: fsys, name: name, f: f}
+}
+
+var _ webdav.File = (*roFile)(nil)
+
+func (f *roFile) Write(p []byte) (n int, err error) {
+	return 0, fs.ErrPermission
+}
+
+func (f *roFile) Close() error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.f == nil {
+		return nil
+	}
+	err := f.f.Close()
+	f.f = nil
+	f.dirList = nil
+	f.dirPos = 0
+	return err
+}
+
+func (f *roFile) Read(p []byte) (int, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
+	if f.f == nil {
+		return 0, fs.ErrClosed
+	}
+	r, ok := f.f.(io.Reader)
+	if !ok {
+		return 0, fs.ErrInvalid
+	}
+	return r.Read(p)
+}
+
+func (f *roFile) Seek(offset int64, whence int) (int64, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
+	if f.f == nil {
+		return 0, fs.ErrClosed
+	}
+	rs, ok := f.f.(io.Seeker)
+	if !ok {
+		return 0, errors.New("seek not supported")
+	}
+	return rs.Seek(offset, whence)
+}
+
+func (f *roFile) Stat() (os.FileInfo, error) {
+	return fs.Stat(f.fsys, f.name)
+}
+
+func (f *roFile) Readdir(count int) ([]os.FileInfo, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
+	if f.f == nil {
+		return nil, fs.ErrClosed
+	}
+
+	fi, err := fs.Stat(f.fsys, f.name)
+	if err != nil {
+		return nil, err
+	}
+	if !fi.IsDir() {
+		return nil, fs.ErrInvalid
+	}
+
+	if f.dirList == nil {
+		des, err := fs.ReadDir(f.fsys, f.name)
+		if err != nil {
+			return nil, err
+		}
+		f.dirList = des
+		f.dirPos = 0
+	}
+
+	if count <= 0 {
+		out := make([]os.FileInfo, 0, len(f.dirList)-f.dirPos)
+		for f.dirPos < len(f.dirList) {
+			de := f.dirList[f.dirPos]
+			f.dirPos++
+			info, err := de.Info()
+			if err != nil {
+				continue
+			}
+			out = append(out, info)
+		}
+		return out, nil
+	}
+
+	out := make([]os.FileInfo, 0, count)
+	for f.dirPos < len(f.dirList) && len(out) < count {
+		de := f.dirList[f.dirPos]
+		f.dirPos++
+		info, err := de.Info()
+		if err != nil {
+			continue
+		}
+		out = append(out, info)
+	}
+
+	if len(out) == 0 {
+		return nil, io.EOF
+	}
+	return out, nil
+}
+
+// --- path helpers ---
+func cleanWebDAVPath(name string) string {
+	if name == "" || name == "/" {
+		return "."
+	}
+	name = path.Clean("/" + name)
+	name = name[1:]
+	if name == "" {
+		return "."
+	}
+	return name
+}
+
+func nonZeroTime(t time.Time) time.Time {
+	if t.IsZero() {
+		return time.Unix(0, 0)
+	}
+	return t
+}