aferodav

github.com/lib-x/aferodav — bidirectional adapters between golang.org/x/net/webdav and github.com/spf13/afero.

Two adapters

New — webdav.FileSystem → afero.Fs

Wrap any webdav.FileSystem so it can be used wherever afero.Fs is expected.

var wdfs webdav.FileSystem = myWebDAVBackend()
afs := aferodav.New(wdfs, context.Background())

// use with any afero-aware library
data, _ := afero.ReadFile(afs, "/notes/hello.txt")

NewFS — afero.Fs → webdav.FileSystem

Wrap any afero.Fs to serve it over WebDAV.

afs := afero.NewMemMapFs() // or OsFs, BasePathFs, your R2Fs, …
handler := &webdav.Handler{
    FileSystem: aferodav.NewFS(afs),
    LockSystem: webdav.NewMemLS(),
}
http.ListenAndServe(":8080", handler)

Installation

go get github.com/lib-x/aferodav

Supported afero backends

Any afero.Fs works with NewFS:

Backend	Notes
afero.NewMemMapFs()	In-memory, great for tests
afero.NewOsFs()	Real OS filesystem
afero.NewBasePathFs(base, dir)	Chroot-like sandbox
afero.NewReadOnlyFs(base)	Read-only view
afero.NewCopyOnWriteFs(base, overlay)	Overlay writes on a read-only base
Custom (S3, GCS, R2, SFTP …)	Anything implementing afero.Fs

Behaviour notes

Feature	New (webdav→afero)	NewFS (afero→webdav)
MkdirAll	Emulated via repeated Mkdir	Delegates to afero.Fs.MkdirAll
Auto-create parent dirs	—	Disabled by default; enable with WithAutoMkdirParents()
Recursive WebDAV MKCOL	—	Disabled by default; enable with WithRecursiveMkdir()
Path validation before path.Clean	Uses built-in normalization	Disabled by default; enable with WithPathCleaner(...)
OpenFile flag rewriting	—	Disabled by default; enable with WithOpenFileFlagMapper(...) or WithObjectStoreWriteMode()
Synthetic Stat for streaming writes	—	Disabled by default; enable with WithSyntheticWriteStat()
Stat fallback / implicit directories	—	Disabled by default; enable with WithStatFallback(...) or WithImplicitDirectoryStat(...)
ReadAt / WriteAt	Emulated via locked Seek + Read/Write	Delegates to afero
Truncate	Emulated (shrink: copy+rewrite)	Delegates to afero
Sync	No-op	Delegates to afero
Chmod / Chown / Chtimes	Unsupported (not in WebDAV)	—

// Optional convenience mode: create missing parents on WebDAV create/rename.
handler := &webdav.Handler{
    FileSystem: aferodav.NewFS(afs, aferodav.WithAutoMkdirParents()),
    LockSystem: webdav.NewMemLS(),
}

NewFS options

NewFS keeps normal webdav.FileSystem / os semantics by default. The options below are opt-in because object stores and regular filesystems need different behavior.

Option	Default result	Enabled result
WithAutoMkdirParents()	OpenFile(O_CREATE) and Rename fail when the destination parent is missing.	Missing parent directories are created before create or rename.
WithPathCleaner(cleaner)	Paths are normalized with path.Clean; for example /a/../b becomes /b.	cleaner(op, rawName) runs before normalization and can reject or rewrite the raw path. Use this to preserve stricter path safety rules such as rejecting .., \, Windows drive paths, or NUL bytes.
WithOpenFileFlagMapper(mapper)	OpenFile receives the exact flags supplied by x/net/webdav.	mapper(normalizedName, flag) can rewrite flags or return an error before the underlying afero.Fs.OpenFile call. Multiple mappers run in option order.
WithObjectStoreWriteMode()	PUT/COPY destinations are opened as O_RDWR|O_CREATE|O_TRUNC; non-create property writes may open as O_RDWR.	Create/write opens using O_RDWR are rewritten to O_WRONLY; non-create O_RDWR opens are downgraded to O_RDONLY. This helps S3/R2-like backends that do not support read-write object handles.
WithSyntheticWriteStat()	If a writable file's Stat() fails during PUT, the WebDAV PUT fails before Close().	Writable handles track bytes written and return synthetic FileInfo when the underlying Stat() fails. Existing successful Stat() results still win.
WithStatFallback(fallback)	Stat returns the underlying filesystem error.	fallback(ctx, normalizedName, originalErr) may return replacement FileInfo, or decline and keep the original error.
WithImplicitDirectoryStat(stat)	A missing path is missing, even if object keys exist under that prefix.	When the underlying Stat reports not-exist, stat(normalizedName) may synthesize directory FileInfo, allowing object-store prefixes to appear as WebDAV directories.
WithRecursiveMkdir()	Mkdir creates exactly one path segment and fails when parents are missing.	Mkdir delegates to MkdirAll, so WebDAV MKCOL can create missing parent prefixes.

Example object-store-oriented setup:

handler := &webdav.Handler{
    FileSystem: aferodav.NewFS(
        objectFS,
        aferodav.WithPathCleaner(strictCleanPath),
        aferodav.WithObjectStoreWriteMode(),
        aferodav.WithSyntheticWriteStat(),
        aferodav.WithImplicitDirectoryStat(statImplicitPrefix),
        aferodav.WithRecursiveMkdir(),
    ),
    LockSystem: webdav.NewMemLS(),
}

Running the example

# Serve an in-memory afero.Fs over WebDAV
go run ./example -mode afero-to-webdav -addr :8080

# Use a webdav.FileSystem as an afero.Fs (writes a file, then serves via HTTP)
go run ./example -mode webdav-to-afero -addr :8080

Testing

go test ./...

License

MIT