public Provider getParentProvider() {
        var parent = getParent();
        while (!(parent instanceof Provider)) {
            parent = parent.getParent();
        }
        return (Provider)parent;
    }
Config producer for source, which is contained in a provider.

@author Tony Vaagenes
config-model/src/main/java/com/yahoo/vespa/model/container/search/searchchain/Source.java