feat(editor,storage): storage library to abstract writabble file system

editor/storage/local.go

@@ -0,0 +1,98 @@
+package storage
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"log/slog"
+	"os"
+	"path"
+)
+
+func Newlocal(
+	root *os.Root,
+	logger *slog.Logger,
+) Storage {
+	return &local{
+		log:  logger,
+		root: root,
+	}
+}
+
+type local struct {
+	log  *slog.Logger
+	root *os.Root
+}
+
+var _ Storage = (*local)(nil)
+
+func (files *local) Exists(p string) bool {
+	if _, err := files.root.Stat(p); err != nil {
+		return false
+	}
+	return true
+}
+
+func (files *local) Open(p string) (fs.File, error) {
+	log := files.log.With(
+		slog.String("path", p),
+		slog.String("root", files.root.Name()))
+
+	log.Debug("Opening file")
+	defer log.Debug("File opened")
+
+	f, err := files.root.Open(p)
+	if errors.Is(err, os.ErrNotExist) {
+		return nil, ErrNotExists
+	} else if err != nil {
+		return nil, err
+	}
+
+	return f, nil
+}
+
+func (files *local) Write(p string, d []byte) (int, error) {
+	log := files.log.With(
+		slog.String("path", p),
+		slog.String("root", files.root.Name()))
+
+	log.Debug("Writing file")
+	defer log.Debug("File wrote")
+
+	if err := files.root.MkdirAll(path.Dir(p), os.ModePerm); err != nil {
+		return 0, fmt.Errorf("file.local: failed to create parent directories %q: %w", path.Dir(p), err)
+	}
+
+	err := files.root.WriteFile(p, d, os.ModePerm)
+	if err != nil {
+		return 0, fmt.Errorf("file.local: failed to write file %q: %w", p, err)
+	}
+
+	return len(d), nil
+}
+
+func (files *local) WriteFrom(p string, r io.Reader) (int64, error) {
+	log := files.log.With(
+		slog.String("path", p),
+		slog.String("root", files.root.Name()))
+
+	log.Debug("Writing file")
+	defer log.Debug("File wrote")
+
+	if err := files.root.MkdirAll(path.Dir(p), os.ModePerm); err != nil {
+		return 0, fmt.Errorf("file.local: failed to create parent directories %q: %w", path.Dir(p), err)
+	}
+
+	f, err := files.root.Create(p)
+	if err != nil {
+		return 0, fmt.Errorf("file.local: failed to create file %q: %w", p, err)
+	}
+
+	n, err := f.ReadFrom(r)
+	if err != nil {
+		return 0, fmt.Errorf("file.local: failed to write file %q: %w", p, err)
+	}
+
+	return n, nil
+}

editor/storage/storage.go

@@ -0,0 +1,42 @@
+package storage
+
+import (
+	"io"
+	"io/fs"
+	"os"
+	"path"
+)
+
+type Storage interface {
+	Exists(p string) bool
+	Open(p string) (fs.File, error)
+	Write(p string, b []byte) (int, error)
+	WriteFrom(p string, r io.Reader) (int64, error)
+}
+
+type withRoot struct {
+	root string
+	Storage
+}
+
+func WithRoot(rootDir string, s Storage) Storage {
+	return &withRoot{root: rootDir, Storage: s}
+}
+
+func (f *withRoot) Exists(p string) bool {
+	return f.Storage.Exists(path.Join(f.root, p))
+}
+
+func (f *withRoot) Open(p string) (fs.File, error) {
+	return f.Storage.Open(path.Join(f.root, p))
+}
+
+func (f *withRoot) Write(p string, b []byte) (int, error) {
+	return f.Storage.Write(path.Join(f.root, p), b)
+}
+
+func (f *withRoot) WriteFrom(p string, r io.Reader) (int64, error) {
+	return f.Storage.WriteFrom(path.Join(f.root, p), r)
+}
+
+var ErrNotExists = os.ErrNotExist