python neo4j报错

Question

在用python neo4j建立数据集的时候，参考了网上的代码进行学习但第一步就开始报错了，看不懂报错什么意思，求指导

代码如下

from py2neo import Graph, Node, Relationship, NodeMatcher
from py2neo.matching import RelationshipMatcher

graph = Graph("http://localhost:7474", username="neo4j", password='20050410Gq')

p1 = Node("drug", name="伸腿瞪眼丸")
p2 = Node("disease", name="精神恍惚")
graph.create(p1)
graph.create(p2)

r = Relationship(p1, "特效治疗", p2)
graph.create(r)

报错为

Traceback (most recent call last):
  File "D:\pycharm\work\pythonProject\medical.py", line 5, in <module>
    graph = Graph("http://localhost:7474", username="neo4j", password='20050410Gq')
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Surface\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\py2neo\database.py", line 288, in __init__
    self.service = GraphService(profile, **settings)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Surface\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\py2neo\database.py", line 115, in __init__
    profile = ServiceProfile(profile, **settings)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Surface\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\py2neo\__init__.py", line 475, in __init__
    super(ServiceProfile, self).__init__(profile, **settings)
  File "C:\Users\Surface\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\py2neo\__init__.py", line 190, in __init__
    self._apply_settings(**settings)
  File "C:\Users\Surface\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\py2neo\__init__.py", line 510, in _apply_settings
    return super(ServiceProfile, self)._apply_settings(uri, scheme, protocol, secure, verify,
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Surface\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\py2neo\__init__.py", line 293, in _apply_settings
    raise ValueError("The following settings are not supported: %r" % other)
ValueError: The following settings are not supported: {'username': 'neo4j'}

neo4j界面为

Answer 1

根据你提供的错误信息，问题出在创建 Graph 对象时传递的参数上。错误信息 ValueError: The following settings are not supported: {'username': 'neo4j'} 表明 username 这个设置是不被支持的。

在较新版本的 py2neo 中，连接 Neo4j 的方式有所变化。你需要使用 auth 参数而不是 username 和 password 分别作为参数。以下是修改后的代码：

from py2neo import Graph, Node, Relationship

# 使用 auth 参数连接 Neo4j
graph = Graph("http://localhost:7474", auth=("neo4j", "20050410Gq"))

# 创建节点
p1 = Node("drug", name="伸腿瞪眼丸")
p2 = Node("disease", name="精神恍惚")
graph.create(p1)
graph.create(p2)

# 创建关系
r = Relationship(p1, "特效治疗", p2)
graph.create(r)

这里的关键修改是将 Graph 对象的初始化参数从 username 和 password 改为 auth，其中 auth 是一个包含用户名和密码的元组。

确保你的 Neo4j 服务正在运行，并且端口 7474 是开放的。如果你的 Neo4j 服务使用的不是默认端口，或者你使用了不同的认证方式（如使用证书），你需要相应地调整 Graph 对象的初始化参数。