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"""networkx-query public interace definition.""" |
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from typing import Any, Dict, Iterable, Tuple |
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from networkx import Graph |
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from .definition import Evaluator, ParserException |
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from .parser import compile_ast, parse |
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__all__ = ['search_nodes', 'search_edges', 'prepare_query', 'ParserException'] |
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def prepare_query(query: Dict) -> Evaluator: |
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"""Transform expression query as a function. |
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Arguments: |
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query (Dict): expression query as dictionary |
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Returns: |
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(Evaluator): evaluator function |
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Exceptions: |
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(ParserException): if a parse error occurs |
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""" |
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return compile_ast(parse(expra=query)) |
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def search_nodes(graph: Graph, query: Dict) -> Iterable[Any]: |
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"""Search nodes in specified grapg which match query. |
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Arguments: |
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graph (Graph): networkx graph instance |
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query (Dict): query expression |
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Returns: |
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(Iterable[Any]): results as an iterable of node identifier. |
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Exceptions: |
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(ParserException): if a parse error occurs |
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""" |
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_predicate = prepare_query(query) |
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return map( |
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lambda n: n[0], filter(lambda n: n[1], map(lambda node: (node[0], _predicate(node[1])), graph.nodes(data=True))) |
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) |
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def search_edges(graph: Graph, query: Dict) -> Iterable[Tuple]: |
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"""Search edges in specified grapg which match query. |
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Arguments: |
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graph (Graph): networkx graph instance |
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query (Dict): query expression |
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Returns: |
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(Iterable[Tuple]): results as an iterable of edge identifier (tuple). |
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Exceptions: |
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(ParserException): if a parse error occurs |
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""" |
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_predicate = prepare_query(query) |
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return map( |
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lambda n: n[0], |
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filter(lambda n: n[1], map(lambda edge: ((edge[0], edge[1]), _predicate(edge[2])), graph.edges(data=True))), |
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) |
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