add Upload and Download files

internal/services/file_service/service.go

@@ -0,0 +1,39 @@
+package file_service
+
+import (
+	"context"
+	"evening_detective_server/internal/modules/file_storage"
+)
+
+type FileService struct {
+	fileStorage file_storage.IFileStorage
+}
+
+func NewFileService(
+	fileStorage file_storage.IFileStorage,
+) *FileService {
+	return &FileService{
+		fileStorage: fileStorage,
+	}
+}
+
+func (s *FileService) UploadFile(
+	ctx context.Context,
+	file *file_storage.File,
+) (string, error) {
+	if err := s.fileStorage.Put(ctx, file); err != nil {
+		return "", err
+	}
+	return file.Name, nil
+}
+
+func (s *FileService) DownloadFile(
+	ctx context.Context,
+	filename string,
+) (*file_storage.File, error) {
+	file, err := s.fileStorage.Get(ctx, filename)
+	if err != nil {
+		return nil, err
+	}
+	return file, nil
+}