init

internal/storage/local.go

@@ -0,0 +1,127 @@
+package storage
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+type LocalStore struct {
+	rootDir string
+	tempDir string
+}
+
+func NewLocal(rootDir string) (*LocalStore, error) {
+	rootDir = filepath.Clean(rootDir)
+	tempDir := filepath.Join(rootDir, ".tmp")
+
+	for _, dir := range []string{rootDir, tempDir} {
+		if err := os.MkdirAll(dir, 0o750); err != nil {
+			return nil, fmt.Errorf("create artifact directory %s: %w", dir, err)
+		}
+	}
+
+	return &LocalStore{
+		rootDir: rootDir,
+		tempDir: tempDir,
+	}, nil
+}
+
+func (s *LocalStore) RootDir() string {
+	return s.rootDir
+}
+
+func (s *LocalStore) CreateTemp(pattern string) (*os.File, string, error) {
+	file, err := os.CreateTemp(s.tempDir, pattern)
+	if err != nil {
+		return nil, "", fmt.Errorf("create temp file: %w", err)
+	}
+
+	return file, file.Name(), nil
+}
+
+func (s *LocalStore) CommitTemp(tempPath, relativePath string) error {
+	destination, err := s.absolutePath(relativePath)
+	if err != nil {
+		return err
+	}
+
+	if err := os.MkdirAll(filepath.Dir(destination), 0o750); err != nil {
+		return fmt.Errorf("create artifact parent directory: %w", err)
+	}
+
+	if _, err := os.Stat(destination); err == nil {
+		return fmt.Errorf("artifact already exists at %s", relativePath)
+	} else if !os.IsNotExist(err) {
+		return fmt.Errorf("check artifact destination: %w", err)
+	}
+
+	if err := os.Rename(tempPath, destination); err != nil {
+		return fmt.Errorf("move artifact into place: %w", err)
+	}
+
+	return nil
+}
+
+func (s *LocalStore) Remove(relativePath string) error {
+	destination, err := s.absolutePath(relativePath)
+	if err != nil {
+		return err
+	}
+
+	if err := os.Remove(destination); err != nil && !os.IsNotExist(err) {
+		return fmt.Errorf("remove artifact: %w", err)
+	}
+
+	return nil
+}
+
+func (s *LocalStore) RemoveTemp(tempPath string) error {
+	if strings.TrimSpace(tempPath) == "" {
+		return nil
+	}
+
+	if err := os.Remove(tempPath); err != nil && !os.IsNotExist(err) {
+		return fmt.Errorf("remove temp artifact: %w", err)
+	}
+
+	return nil
+}
+
+func (s *LocalStore) Open(relativePath string) (*os.File, error) {
+	destination, err := s.absolutePath(relativePath)
+	if err != nil {
+		return nil, err
+	}
+
+	file, err := os.Open(destination)
+	if err != nil {
+		return nil, fmt.Errorf("open artifact: %w", err)
+	}
+
+	return file, nil
+}
+
+func (s *LocalStore) absolutePath(relativePath string) (string, error) {
+	relativePath = filepath.Clean(strings.TrimSpace(relativePath))
+	if relativePath == "." || relativePath == "" {
+		return "", fmt.Errorf("artifact path is required")
+	}
+
+	if filepath.IsAbs(relativePath) {
+		return "", fmt.Errorf("artifact path must be relative")
+	}
+
+	joined := filepath.Join(s.rootDir, relativePath)
+	rel, err := filepath.Rel(s.rootDir, joined)
+	if err != nil {
+		return "", fmt.Errorf("resolve artifact path: %w", err)
+	}
+
+	if rel == ".." || strings.HasPrefix(rel, ".."+string(filepath.Separator)) {
+		return "", fmt.Errorf("artifact path escapes storage root")
+	}
+
+	return joined, nil
+}