#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright 2020 Alibaba Group Holding Limited. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
import array
import functools
__all__ = ["declare", "Vertex"]
# Emulated PIE type
class GraphScopeMetaType(type):
def __getitem__(type, ix):
return array(type, ix)
GraphScopeTypeObject = GraphScopeMetaType("GrapeTypeObject", (object,), {})
class GraphScopeType(GraphScopeTypeObject):
def __init__(self, name=None):
self.name = name
def __repr__(self):
return self.name
Vertex = GraphScopeType("Vertex")
# Place holder
class __PlaceHolder(object):
"""Access it will trigger an exception"""
def __init__(self, func):
functools.update_wrapper(self, func)
def __getattr__(self, key):
raise RuntimeError("Operation not allowed.")
def __call__(self, *args, **kwargs):
raise RuntimeError("Operation not allowed.")
[docs]def declare(graphscope_type, variable):
"""Declare a GraphScope data type.
Args:
graphscope_type (:class:`graphscope.analytical.udf.GraphScopeType`):
Valid options are `graphscope.Vertex`
variable:
Python variable.
Examples:
>>> @pie(vd_type="string", md_type="string")
>>> class MyAlgorithm(AppAssets):
>>> @staticmethod
>>> def Init(frag, context):
>>> graphscope.declare(graphscope.Vertex, source)
>>> # means `Vertex source;` in c++ code
>>> @staticmethod
>>> def PEval(frag, context):
>>> pass
>>> @staticmethod
>>> def IncEval(frag, context):
>>> pass
"""
return __PlaceHolder(declare)