func listBackupOperations()

in spanner/spanner_snippets/spanner/spanner_list_backup_operations.go [32:100]
60 lines of code
12 McCabe index (conditional complexity)

func listBackupOperations(w io.Writer, db string, backupId string) error {
	// db := "projects/my-project/instances/my-instance/databases/my-database"
	// backupID := "my-backup"

	ctx := context.Background()

	adminClient, err := database.NewDatabaseAdminClient(ctx)
	if err != nil {
		return err
	}
	defer adminClient.Close()

	matches := regexp.MustCompile("^(.*)/databases/(.*)$").FindStringSubmatch(db)
	if matches == nil || len(matches) != 3 {
		return fmt.Errorf("Invalid database id %s", db)
	}
	instanceName := matches[1]
	// List the CreateBackup operations.
	filter := fmt.Sprintf("(metadata.@type:type.googleapis.com/google.spanner.admin.database.v1.CreateBackupMetadata) AND (metadata.database:%s)", db)
	iter := adminClient.ListBackupOperations(ctx, &adminpb.ListBackupOperationsRequest{
		Parent: instanceName,
		Filter: filter,
	})
	for {
		resp, err := iter.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return err
		}
		metadata := &adminpb.CreateBackupMetadata{}
		if err := ptypes.UnmarshalAny(resp.Metadata, metadata); err != nil {
			return err
		}
		fmt.Fprintf(w, "Backup %s on database %s is %d%% complete.\n",
			metadata.Name,
			metadata.Database,
			metadata.Progress.ProgressPercent,
		)
	}

	// List the CopyBackup operations.
	filter = fmt.Sprintf("(metadata.@type:type.googleapis.com/google.spanner.admin.database.v1.CopyBackupMetadata) AND (metadata.source_backup:%s)", backupId)
	iter = adminClient.ListBackupOperations(ctx, &adminpb.ListBackupOperationsRequest{
		Parent: instanceName,
		Filter: filter,
	})
	for {
		resp, err := iter.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return err
		}
		metadata := &adminpb.CopyBackupMetadata{}
		if err := ptypes.UnmarshalAny(resp.Metadata, metadata); err != nil {
			return err
		}
		fmt.Fprintf(w, "Backup %s copied from %s is %d%% complete.\n",
			metadata.Name,
			metadata.SourceBackup,
			metadata.Progress.ProgressPercent,
		)
	}

	return nil
}