Source code for airflow.providers.neo4j.hooks.neo4j
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"""This module allows to connect to a Neo4j database."""
from __future__ import annotations
from typing import TYPE_CHECKING, Any
from urllib.parse import urlsplit
from neo4j import Driver, GraphDatabase
from airflow.hooks.base import BaseHook
if TYPE_CHECKING:
from airflow.models import Connection
[docs]class Neo4jHook(BaseHook):
"""
Interact with Neo4j.
Performs a connection to Neo4j and runs the query.
:param neo4j_conn_id: Reference to :ref:`Neo4j connection id <howto/connection:neo4j>`.
"""
[docs] conn_name_attr = "neo4j_conn_id"
[docs] default_conn_name = "neo4j_default"
def __init__(self, conn_id: str = default_conn_name, *args, **kwargs) -> None:
super().__init__(*args, **kwargs)
self.neo4j_conn_id = conn_id
self.connection = kwargs.pop("connection", None)
self.client: Driver | None = None
[docs] def get_conn(self) -> Driver:
"""Initiate a new Neo4j connection with username, password and database schema."""
if self.client is not None:
return self.client
self.connection = self.get_connection(self.neo4j_conn_id)
uri = self.get_uri(self.connection)
self.log.info("URI: %s", uri)
is_encrypted = self.connection.extra_dejson.get("encrypted", False)
self.client = self.get_client(self.connection, is_encrypted, uri)
return self.client
[docs] def get_client(self, conn: Connection, encrypted: bool, uri: str) -> Driver:
"""
Determine that relevant driver based on extras.
:param conn: Connection object.
:param encrypted: boolean if encrypted connection or not.
:param uri: uri string for connection.
:return: Driver
"""
parsed_uri = urlsplit(uri)
kwargs: dict[str, Any] = {}
if parsed_uri.scheme in ["bolt", "neo4j"]:
kwargs["encrypted"] = encrypted
return GraphDatabase.driver(uri, auth=(conn.login, conn.password), **kwargs)
[docs] def get_uri(self, conn: Connection) -> str:
"""
Build the uri based on extras.
- Default - uses bolt scheme(bolt://)
- neo4j_scheme - neo4j://
- certs_self_signed - neo4j+ssc://
- certs_trusted_ca - neo4j+s://
:param conn: connection object.
:return: uri
"""
use_neo4j_scheme = conn.extra_dejson.get("neo4j_scheme", False)
scheme = "neo4j" if use_neo4j_scheme else "bolt"
# Self signed certificates
ssc = conn.extra_dejson.get("certs_self_signed", False)
# Only certificates signed by CA.
trusted_ca = conn.extra_dejson.get("certs_trusted_ca", False)
encryption_scheme = ""
if ssc:
encryption_scheme = "+ssc"
elif trusted_ca:
encryption_scheme = "+s"
return f"{scheme}{encryption_scheme}://{conn.host}:{7687 if conn.port is None else conn.port}"
[docs] def run(self, query) -> list[Any]:
"""
Create a neo4j session and execute the query in the session.
:param query: Neo4j query
:return: Result
"""
driver = self.get_conn()
if not self.connection.schema:
with driver.session() as session:
result = session.run(query)
return result.data()
else:
with driver.session(database=self.connection.schema) as session:
result = session.run(query)
return result.data()