List parent and children of an LV2 plugin class

lv2_list_class_relations.py

#!/usr/bin/env python

import sys
import lilv


if len(sys.argv) > 1:
    pclass = sys.argv[1]
else:
    pclass = "SimulatorPlugin"

world = lilv.World()
world.load_all()
plugin_classes = world.get_plugin_classes()
plugin_class = plugin_classes.get_by_uri(getattr(world.ns.lv2, pclass))

children = plugin_class.get_children()

if children:
    for child in children:
        print("%s <%s>" % (child.get_label(), child))
else:
    print("Class %s has no children" % (plugin_class.get_label(),))


parent_uri = plugin_class.get_parent_uri()

if parent_uri is not None:
    parent = plugin_classes.get_by_uri(parent_uri)
    print("Class %s parent: %s <%s>" % (plugin_class.get_label(), parent.get_label(), parent_uri))
else:
    print("Class %s has no parent" % (plugin_class.get_label(),))