Connection to database crash while processing multiple queries with Python driver

[carlo_martinott]

I'm trying to create edges from the python API of neo4j using a neo4j docker image. basically I launch the following script:

from neo4j import GraphDatabase
server='bolt://localhost:7687'
usr="neo4j"
pwd="jdl"

driver = GraphDatabase.driver(server, auth=(usr, pwd))
for line in tqdm.tqdm(big_mat[0:1000]):
        query_line=f"""MATCH (s:Sample)-[r]->(m:Mineral)
        WHERE s.id='{line[0]}' AND m.name='{line[2]}'
        SET r.amount_weighted={line[1]}
        """
        driver.session().run(query_line)

and for whatever reason it does a bunch of iterations (which is variable between about 70 and a hundred) and then crashes outputting this error which I cannot really understand..

---------------------------------------------------------------------------
ClientError                               Traceback (most recent call last)
Input In [257], in <cell line: 6>()
      6 for line in tqdm.tqdm(big_mat[0:1000]):
      7         query_line=f"""MATCH (s:Sample)-[r]->(m:Mineral)
      8         WHERE s.id='{line[0]}' AND m.name='{line[2]}'
      9         SET r.amount_weighted={line[1]}
     10         """
---> 11         driver.session().run(query_line)

File ~/anaconda3/envs/Jdl_geochemical/lib/python3.9/site-packages/neo4j/work/simple.py:204, in Session.run(self, query, parameters, **kwparameters)
    201     self._autoResult._buffer_all()  # This will buffer upp all records for the previous auto-transaction
    203 if not self._connection:
--> 204     self._connect(self._config.default_access_mode)
    205 cx = self._connection
    206 protocol_version = cx.PROTOCOL_VERSION

File ~/anaconda3/envs/Jdl_geochemical/lib/python3.9/site-packages/neo4j/work/simple.py:108, in Session._connect(self, access_mode)
    106 if access_mode is None:
    107     access_mode = self._config.default_access_mode
--> 108 super()._connect(access_mode)

File ~/anaconda3/envs/Jdl_geochemical/lib/python3.9/site-packages/neo4j/work/__init__.py:79, in Workspace._connect(self, access_mode)
     66     else:
     67         # This is the first time we open a connection to a server in a
     68         # cluster environment for this session without explicitly
   (...)
     71         # we shall use this database explicitly for all subsequent
     72         # actions within this session.
     73         self._pool.update_routing_table(
     74             database=self._config.database,
     75             imp_user=self._config.impersonated_user,
     76             bookmarks=self._bookmarks,
     77             database_callback=self._set_cached_database
     78         )
---> 79 self._connection = self._pool.acquire(
     80     access_mode=access_mode,
     81     timeout=self._config.connection_acquisition_timeout,
     82     database=self._config.database,
     83     bookmarks=self._bookmarks
     84 )
     85 self._connection_access_mode = access_mode

File ~/anaconda3/envs/Jdl_geochemical/lib/python3.9/site-packages/neo4j/io/__init__.py:842, in BoltPool.acquire(self, access_mode, timeout, database, bookmarks)
    840 def acquire(self, access_mode=None, timeout=None, database=None, bookmarks=None):
    841     # The access_mode and database is not needed for a direct connection, its just there for consistency.
--> 842     return self._acquire(self.address, timeout)

File ~/anaconda3/envs/Jdl_geochemical/lib/python3.9/site-packages/neo4j/io/__init__.py:715, in IOPool._acquire(self, address, timeout)
    710     # if timed out, then we throw error. This time
    711     # computation is needed, as with python 2.7, we
    712     # cannot tell if the condition is notified or
    713     # timed out when we come to this line
    714     if not time_remaining():
--> 715         raise ClientError("Failed to obtain a connection from pool "
    716                           "within {!r}s".format(timeout))
    717 else:
    718     raise ClientError("Failed to obtain a connection from pool "
    719                       "within {!r}s".format(timeout))

ClientError: {code: None} {message: None}

Am I trying to upload edges in the wrong way?