Is there a simple example of working with the neo4j python driver?
How do I just pass cypher query to the driver to run and return a cursor?
If I'm reading for example this it seems the demo has a class wrapper, with a private member func I pass to the session.write,
session.write_transaction(self._create_and_return_greeting, ...
That then gets called it with a transaction as a first parameter...
def _create_and_return_greeting(tx, message):
that in turn runs the cypher
result = tx.run("CREATE (a:Greeting) "
This seems 10X more complicated than it needs to be.
I did just try a simpler:
def raw_query(query, **kwargs):
neodriver = neo_connect() # cached dbconn
with neodriver.session() as session:
try:
result = session.run(query, **kwargs)
return result.data()
But this results in a socket error on the query, probably because the session goes out of scope?
[dfcx/__init__] ERROR | Underlying socket connection gone (_ssl.c:2396)
[dfcx/__init__] ERROR | Failed to write data to connection IPv4Address(('neo4j-core-8afc8558-3.production-orch-0042.neo4j.io', 7687)) (IPv4Address(('34.82.120.138', 7687)))
Also I can't return a cursor/iterator, just the data()
When the session goes out of scope, the query result seems to die with it.
If I manually open and close a session, then I'd have the same problems?
Python must be the most popular language this DB is used with, does everyone use a different driver?
Py2neo seems cute, but completely lacking in ORM wrapper function for most of the cypher language features, so you have to drop down to raw cypher anyway. And I'm not sure it supports **kwargs argument interpolation in the same way.
I guess that $300M raise got blown on marketing.
Slightly longer version trying to get a working DB wrapper:
def neo_connect() -> Union[neo4j.BoltDriver, neo4j.Neo4jDriver]:
global raw_driver
if raw_driver:
# print('reuse driver')
return raw_driver
neoconfig = NEOCONFIG
raw_driver = neo4j.GraphDatabase.driver(
neoconfig['url'], auth=(
neoconfig['user'], neoconfig['pass']))
if raw_driver is None:
raise BaseException("cannot connect to neo4j")
else:
return raw_driver
def raw_query(query, **kwargs):
# just get data, no cursor
neodriver = neo_connect()
session = neodriver.session()
# logging.info('neoquery %s', query)
# with neodriver.session() as session:
try:
result = session.run(query, **kwargs)
data = result.data()
return data
except neo4j.exceptions.CypherSyntaxError as err:
logging.error('neo error %s', err)
logging.error('failed query: %s', query)
raise err
# finally:
# logging.info('close session')
# session.close()
