FIX: Gap Of Uploading The Same File Key Twice

cms/internal/db/repositories/videos.go

@@ -14,6 +14,19 @@ type VideoRepository struct {
 
 var VideoRepo VideoRepository
 
+// VideoExistsWithStorageKey reports whether a video has already been
+// registered under a storage key. It is served by videos_storage_key_key, the
+// index Postgres builds for the column's UNIQUE constraint.
+func (svc VideoRepository) VideoExistsWithStorageKey(ctx context.Context, storageKey string) (bool, error) {
+	var exists bool
+	err := svc.SQLDB.QueryRowContext(ctx,
+		`SELECT EXISTS (SELECT 1 FROM videos WHERE storage_key = $1)`, storageKey).Scan(&exists)
+	if err != nil {
+		return false, err
+	}
+	return exists, nil
+}
+
 func (svc VideoRepository) CreateVideo(ctx context.Context, v models.Video) (models.Video, error) {
 	tx, err := svc.SQLDB.BeginTx(ctx, nil)
 	if err != nil {