from functools import partial from inspect import isclass from ..types import Field, Interface, ObjectType from ..types.interface import InterfaceOptions from ..types.utils import get_type from .id_type import BaseGlobalIDType, DefaultGlobalIDType def is_node(objecttype): """ Check if the given objecttype has Node as an interface """ if not isclass(objecttype): return False if not issubclass(objecttype, ObjectType): return False return any(issubclass(i, Node) for i in objecttype._meta.interfaces) class GlobalID(Field): def __init__( self, node=None, parent_type=None, required=True, global_id_type=DefaultGlobalIDType, *args, **kwargs, ): super(GlobalID, self).__init__( global_id_type.graphene_type, required=required, *args, **kwargs ) self.node = node or Node self.parent_type_name = parent_type._meta.name if parent_type else None @staticmethod def id_resolver(parent_resolver, node, root, info, parent_type_name=None, **args): type_id = parent_resolver(root, info, **args) parent_type_name = parent_type_name or info.parent_type.name return node.to_global_id(parent_type_name, type_id) # root._meta.name def wrap_resolve(self, parent_resolver): return partial( self.id_resolver, parent_resolver, self.node, parent_type_name=self.parent_type_name, ) class NodeField(Field): def __init__(self, node, type_=False, **kwargs): assert issubclass(node, Node), "NodeField can only operate in Nodes" self.node_type = node self.field_type = type_ global_id_type = node._meta.global_id_type super(NodeField, self).__init__( # If we don't specify a type, the field type will be the node interface type_ or node, id=global_id_type.graphene_type( required=True, description="The ID of the object" ), **kwargs, ) def wrap_resolve(self, parent_resolver): return partial(self.node_type.node_resolver, get_type(self.field_type)) class AbstractNode(Interface): class Meta: abstract = True @classmethod def __init_subclass_with_meta__(cls, global_id_type=DefaultGlobalIDType, **options): assert issubclass( global_id_type, BaseGlobalIDType ), "Custom ID type need to be implemented as a subclass of BaseGlobalIDType." _meta = InterfaceOptions(cls) _meta.global_id_type = global_id_type _meta.fields = { "id": GlobalID( cls, global_id_type=global_id_type, description="The ID of the object" ) } super(AbstractNode, cls).__init_subclass_with_meta__(_meta=_meta, **options) @classmethod def resolve_global_id(cls, info, global_id): return cls._meta.global_id_type.resolve_global_id(info, global_id) class Node(AbstractNode): """An object with an ID""" @classmethod def Field(cls, *args, **kwargs): # noqa: N802 return NodeField(cls, *args, **kwargs) @classmethod def node_resolver(cls, only_type, root, info, id): return cls.get_node_from_global_id(info, id, only_type=only_type) @classmethod def get_node_from_global_id(cls, info, global_id, only_type=None): _type, _id = cls.resolve_global_id(info, global_id) graphene_type = info.schema.get_type(_type) if graphene_type is None: raise Exception(f'Relay Node "{_type}" not found in schema') graphene_type = graphene_type.graphene_type if only_type: assert ( graphene_type == only_type ), f"Must receive a {only_type._meta.name} id." # We make sure the ObjectType implements the "Node" interface if cls not in graphene_type._meta.interfaces: raise Exception( f'ObjectType "{_type}" does not implement the "{cls}" interface.' ) get_node = getattr(graphene_type, "get_node", None) if get_node: return get_node(info, _id) @classmethod def to_global_id(cls, type_, id): return cls._meta.global_id_type.to_global_id(type_, id)