Add admin panel: visit counter, product editor, screenshots upload

internal/upload/storage.go

@@ -0,0 +1,85 @@
+package upload
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"mime/multipart"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/google/uuid"
+)
+
+var allowedTypes = map[string]string{
+	"image/jpeg": ".jpg",
+	"image/png":  ".png",
+	"image/webp": ".webp",
+	"image/gif":  ".gif",
+}
+
+type Storage struct {
+	RootDir string
+}
+
+func NewStorage(root string) (*Storage, error) {
+	if err := os.MkdirAll(root, 0755); err != nil {
+		return nil, err
+	}
+	return &Storage{RootDir: root}, nil
+}
+
+func (s *Storage) SaveProductImage(productID int, file multipart.File, header *multipart.FileHeader) (string, error) {
+	buf := make([]byte, 512)
+	n, err := file.Read(buf)
+	if err != nil && err != io.EOF {
+		return "", err
+	}
+	contentType := http.DetectContentType(buf[:n])
+	ext, ok := allowedTypes[contentType]
+	if !ok {
+		return "", fmt.Errorf("недопустимый тип файла: %s", contentType)
+	}
+
+	if _, err := file.Seek(0, io.SeekStart); err != nil {
+		return "", err
+	}
+
+	dir := filepath.Join(s.RootDir, "products", fmt.Sprintf("%d", productID))
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return "", err
+	}
+
+	name := uuid.New().String() + ext
+	fullPath := filepath.Join(dir, name)
+
+	dst, err := os.Create(fullPath)
+	if err != nil {
+		return "", err
+	}
+	defer dst.Close()
+
+	if _, err := io.Copy(dst, io.MultiReader(bytes.NewReader(buf[:n]), file)); err != nil {
+		os.Remove(fullPath)
+		return "", err
+	}
+
+	webPath := "/uploads/products/" + fmt.Sprintf("%d", productID) + "/" + name
+	_ = header
+	return webPath, nil
+}
+
+func (s *Storage) Remove(webPath string) error {
+	if !strings.HasPrefix(webPath, "/uploads/") {
+		return nil
+	}
+	rel := strings.TrimPrefix(webPath, "/uploads/")
+	full := filepath.Join(s.RootDir, rel)
+	return os.Remove(full)
+}
+
+func (s *Storage) FileServer() http.Handler {
+	return http.StripPrefix("/uploads/", http.FileServer(http.Dir(s.RootDir)))
+}