将Neo4j查询结果转换为D3兼容的Graph JSON格式教程

{
  "records": [
    {
      "_fields": [
        {
          "identity": { "low": 0, "high": 0 },
          "labels": ["Person"],
          "properties": { "name": "Alice" }
        },
        {
          "identity": { "low": 1, "high": 0 },
          "labels": ["Movie"],
          "properties": { "title": "Inception" }
        },
        {
          "identity": { "low": 0, "high": 0 },
          "start": { "low": 0, "high": 0 },
          "end": { "low": 1, "high": 0 },
          "type": "ACTED_IN",
          "properties": { "roles": ["Cobb"] }
        }
      ],
      "_fieldLookup": { "n": 0, "m": 1, "r": 2 }
    }
  ]
}

{
  "nodes": [
    { "id": "n0", "label": "Alice", "group": 1 },
    { "id": "n1", "label": "Inception", "group": 2 }
  ],
  "links": [
    { "source": "n0", "target": "n1", "value": 1 }
  ]
}

MATCH (n:MyNode)-[r:MY_REL]-()
WITH COLLECT(n) AS mynodes, COLLECT(r) AS myrels
CALL apoc.export.json.data(mynodes, myrels, null, {stream: true, jsonFormat: "JSON", writeNodeProperties: true, writeRelationshipProperties: true})
YIELD data
RETURN data

import neo4j from 'neo4j-driver';
import {
  NEO4J_PASSWORD,
  NEO4J_URL,
  NEO4J_USERNAME,
} from '../../constants/index.js';

export const runMatchQuery = async (req, res) => {
  // 假设前端传递的query现在是包含APOC调用的Cypher语句
  const query = req?.body?.query; 

  // 建议在这里对查询进行更严格的验证，以防止注入或不安全的APOC调用
  // For demonstration, we assume a valid APOC query is provided.

  const driver = neo4j.driver(
    NEO4J_URL,
    neo4j.auth.basic(NEO4J_USERNAME, NEO4J_PASSWORD)
  );
  const session = driver.session();

  try {
    const result = await session.run(query);

    // APOC的apoc.export.json.data会返回一个包含'data'字段的Record
    // 'data'字段即为我们所需的Graph JSON字符串
    const graphJsonString = result.records[0].get('data');
    const graphJson = JSON.parse(graphJsonString); // 解析为JavaScript对象

    return res.status(200).json(graphJson); // 返回解析后的Graph JSON对象
  } catch (error) {
    console.error('Neo4j query error:', error); // 使用console.error记录错误
    return res.status(500).json({ message: error.message || 'An unexpected error occurred.' });
  } finally {
    await session.close();
    await driver.close();
  }
};