Tencent/WeKnora · error · ErrCrossBackendCopy

minio copy rejected source %q: %w

Error message

minio copy rejected source %q: %w

What it means

Cross-backend copy guard: the source path failed to parse as a minio:// path, so it belongs to a different storage backend; the copy is rejected with the ErrCrossBackendCopy sentinel because a server-side MinIO CopyObject is impossible across backends.

Source

Thrown at internal/application/service/file/minio.go:183

		return err
	}
	if err := s.client.RemoveObject(ctx, s.bucketName, objectName, minio.RemoveObjectOptions{
		GovernanceBypass: true,
	}); err != nil {
		return fmt.Errorf("failed to delete file: %w", err)
	}
	return nil
}

// CopyFile copies an existing MinIO object to a new knowledge-owned object using a
// server-side CopyObject (no data leaves MinIO). The destination uses the same
// layout as SaveFile. Returns ErrCrossBackendCopy when srcPath is not a minio:// path.
func (s *minioFileService) CopyFile(ctx context.Context,
	srcPath string, tenantID uint64, knowledgeID string,
) (string, error) {
	srcKey, err := s.parseMinioFilePath(srcPath)
	if err != nil {
		return "", fmt.Errorf("minio copy rejected source %q: %w", srcPath, ErrCrossBackendCopy)
	}

	ext := filepath.Ext(srcPath)
	destKey := fmt.Sprintf("%d/%s/%s%s", tenantID, knowledgeID, uuid.New().String(), ext)

	_, err = s.client.CopyObject(ctx,
		minio.CopyDestOptions{Bucket: s.bucketName, Object: destKey},
		minio.CopySrcOptions{Bucket: s.bucketName, Object: srcKey},
	)
	if err != nil {
		return "", fmt.Errorf("failed to copy file in MinIO: %w", err)
	}

	newPath := fmt.Sprintf("minio://%s/%s", s.bucketName, destKey)
	logger.Infof(ctx, "Copied MinIO object %s to %s", srcPath, newPath)
	return newPath, nil
}

View on GitHub (pinned to 988cbb0330)

Solutions

1. Route the copy to the backend that owns the source path
2. Download from the source backend and re-upload to MinIO if cross-backend copy is required
3. Check for the sentinel with errors.Is in callers

When it happens

Trigger: Thrown at internal/application/service/file/minio.go:183 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of Tencent/WeKnora@988cbb0330 (2026-09-02). Data as JSON: /api/errors/2fcba1f526de1dbc. Report an issue: GitHub.