What causes "failed to delete materialized view: %w" in googleapis/mcp-toolbox?

Handle codes.NotFound as success for idempotent deletes via status.FromError on the wrapped error

failed to delete materialized view: %w

Error message

failed to delete materialized view: %w

What it means

DeleteMaterializedView wraps errors from InstanceAdmin.DeleteMaterializedView. Deletion fails when the view does not exist (NotFound), permissions are missing, or a transient gRPC error occurs. The original error is preserved via %w for programmatic inspection.

Source

Thrown at internal/sources/bigtable/admin_wrappers.go:272

	return map[string]string{"status": "materialized view created successfully"}, nil
}

func (s *Source) UpdateMaterializedView(ctx context.Context, instanceId, materializedViewId, query string) (any, error) {
	conf := bigtable.MaterializedViewInfo{ // MUST be value per bigtable SDK
		MaterializedViewID: materializedViewId,
		Query:              query,
	}
	err := s.InstanceAdmin.UpdateMaterializedView(ctx, instanceId, conf)
	if err != nil {
		return nil, fmt.Errorf("failed to update materialized view: %w", err)
	}
	return map[string]string{"status": "materialized view updated successfully"}, nil
}

func (s *Source) DeleteMaterializedView(ctx context.Context, instanceId, materializedViewId string) (any, error) {
	err := s.InstanceAdmin.DeleteMaterializedView(ctx, instanceId, materializedViewId)
	if err != nil {
		return nil, fmt.Errorf("failed to delete materialized view: %w", err)
	}
	return map[string]string{"status": "materialized view deleted successfully"}, nil
}

View on GitHub (pinned to 8cc6e09de2)

Solutions

Handle codes.NotFound as success for idempotent deletes via status.FromError on the wrapped error
Confirm the ID belongs to a materialized view, not a logical view
Grant roles/bigtable.admin or the delete permission to the caller
Retry on Unavailable/DeadlineExceeded

Example fix

// before: rerun of cleanup fails
err := s.InstanceAdmin.DeleteMaterializedView(ctx, instanceId, id)
// after: idempotent handling
err := s.InstanceAdmin.DeleteMaterializedView(ctx, instanceId, id)
if err != nil && status.Code(err) != codes.NotFound {
    return nil, fmt.Errorf("failed to delete materialized view: %w", err)
}

Defensive patterns

Strategy: try-catch

Validate before calling

views, err := src.ListMaterializedViews(ctx, instanceId)
if err != nil { return err }
if !containsMaterializedViewID(views, viewId) {
    return nil // already absent; treat delete as no-op
}

Type guard

func isNotFound(err error) bool {
    st, ok := status.FromError(errors.Unwrap(err))
    return ok && st.Code() == codes.NotFound
}

Try / catch

res, err := src.DeleteMaterializedView(ctx, instanceId, viewId)
switch {
case err == nil:
    // deleted
case isNotFound(err):
    // already deleted: success
default:
    return err
}

Prevention

Make cleanup idempotent by treating NotFound as success
Use the correct tool per namespace: logical views vs materialized views
Verify delete permission (roles/bigtable.admin) before running teardown scripts
Add retry with backoff for transient gRPC failures

When it happens

Trigger: Calling DeleteMaterializedView (bigtable_delete_materialized_view tool) when: materializedViewId was already deleted or never existed, the instanceId is wrong, caller lacks delete permission, or the admin RPC fails transiently.

Common situations: Non-idempotent cleanup scripts double-deleting; deleting a logical view ID with the materialized-view tool (separate namespaces); IAM role removals; transient API outages.

Related errors

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/ec0edd0a3cbb5ba6. Report an issue: GitHub.