feat(API): media library

internal/infrastructure/useCases/mediaUploader.go

@@ -0,0 +1,40 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/user"
+	"errors"
+)
+
+type uploaderNames struct {
+	userRepository user.Repository
+	names          map[uint32]string
+}
+
+func newUploaderNames(userRepository user.Repository) *uploaderNames {
+	return &uploaderNames{userRepository: userRepository, names: map[uint32]string{}}
+}
+
+func (u *uploaderNames) nameOf(userId uint32) (string, error) {
+	if userId == 0 {
+		return "", nil
+	}
+	if name, ok := u.names[userId]; ok {
+		return name, nil
+	}
+
+	uploader, err := u.userRepository.Get(userId)
+	if errors.Is(err, user.ErrUserNotFound) {
+		u.names[userId] = ""
+		return "", nil
+	}
+	if err != nil {
+		return "", err
+	}
+
+	name := uploader.DisplayName
+	if name == "" {
+		name = uploader.Username
+	}
+	u.names[userId] = name
+	return name, nil
+}