I have installed neo4j desktop and I am able to use neo4j database from it. The problem is when I try to connect to neo4j database from a Django project.
I have configured my settings.py with config.DATABASE_URL = 'bolt://neo4j:neo4j#localhost:7687', but when I run neomodel_install-labels, I get this error:
Connecting to bolt://neo4j:neo4j#localhost:7687
Traceback (most recent call last):
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/bolt/connection.py",
line 578, in _connect
s.connect(resolved_address)
ConnectionRefusedError: [Errno 61] Connection refused
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/bin/neomodel_install_labels", line 67, in <module>
main()
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/bin/neomodel_install_labels", line 62, in main
db.set_connection(bolt_url)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neomodel/util.py", line 65,
in set_connection
max_pool_size=config.MAX_POOL_SIZE)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/v1/api.py", line 94,
in driver
return Driver(uri, **config)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/v1/api.py", line 133,
in __new__
return subclass(uri, **config)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/v1/direct.py", line 7
3, in __new__
pool.release(pool.acquire())
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/v1/direct.py", line 4
4, in acquire
return self.acquire_direct(self.address)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/bolt/connection.py",
line 453, in acquire_direct
connection = self.connector(address, self.connection_error_handler)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/v1/direct.py", line 7
0, in connector
return connect(address, security_plan.ssl_context, error_handler, **config)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/bolt/connection.py",
line 707, in connect
raise last_error
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/bolt/connection.py",
line 697, in connect
s = _connect(resolved_address, **config)
File "/Users/hugovillalobos/Documents/Code/AttractoraProject/AttractoraVenv/lib/python3.6/site-packages/neo4j/bolt/connection.py",
line 587, in _connect
raise ServiceUnavailable("Failed to establish connection to {!r} (reason {})".format(resolved_address, error.errno))
neo4j.exceptions.ServiceUnavailable: Failed to establish connection to ('::1', 7687, 0, 0) (reason 61)
I know the database is running because I can connect from neo4j desktop, and I have installed neo4j-driver and neomodel. I don't know what I am missing.
Ok, I don't know if this apply to any case, and I don't know the reason for it, but I found that it was a matter of spacial characters in the password. I set my password with an exclamation character, and when I was trying to connect, it failed. I changed the password for the user in Neo4j removing the exclamation character and Bingo! I got a connection. Can anybody tell my why this happens?
Related
Inserting via debezium connector to mysql database brought up via docker container.
Trying to query and it is working fine until some number of hours. But, after that, same query is throwing below exception.
export JAVA_HOME=/tmp/tests/artifacts/java-17/jdk-17; export PATH=$PATH:/tmp/tests/artifacts/java-17/jdk-17/bin; docker exec -i mysql_be1e6a mysql --user=demo --password=demo -D demo -e "select count(k) from test_cdc_f0bf84 where uuid = 'd1e5cd6d-8f7a-457c-b2ea-880c2be52f69'"
2023-01-02 16:27:43,812:ERROR: failed to execute query MySQL rows count by uuid:
Traceback (most recent call last):
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/env/lib/python3.11/site-packages/paramiko/channel.py", line 699, in recv
out = self.in_buffer.read(nbytes, self.timeout)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/env/lib/python3.11/site-packages/paramiko/buffered_pipe.py", line 164, in read
raise PipeTimeout()
paramiko.buffered_pipe.PipeTimeout
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/suites/cdc/abstract.py", line 667, in try_query
res = query_function()
^^^^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/suites/cdc/test_cdc.py", line 635, in <lambda>
query = lambda: self.mysql_query(
^^^^^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/suites/cdc/abstract.py", line 544, in mysql_query
result = self.ssh.exec_on_host(host, [
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/main/connection.py", line 335, in exec_on_host
return self._exec_on_host(host, commands, fetch, timeout=timeout, limit_output=limit_output)[host]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/main/connection.py", line 321, in _exec_on_host
res = list(out)
^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/env/lib/python3.11/site-packages/paramiko/file.py", line 125, in __next__
line = self.readline()
^^^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/env/lib/python3.11/site-packages/paramiko/file.py", line 291, in readline
new_data = self._read(n)
^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/env/lib/python3.11/site-packages/paramiko/channel.py", line 1361, in _read
return self.channel.recv(size)
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/ubuntu/workspace/stress_tests/run_test_with_universe/src/env/lib/python3.11/site-packages/paramiko/channel.py", line 701, in recv
raise socket.timeout()
TimeoutError
After some time, logged manually to machine and tried to read, it still reads fine. Not sure, what does this issue mean.
As explained, tried querying from database via python. Expected it will return count of rows, which it was happening until certain time, but after that, it threw timeout error and socket error.
Trying to query and it is working fine until some number of hours. But, after that, same query is throwing below exception.
The default value for interactive_timeout and wait_timeout is 28880 seconds (8 hours). you can disable this behavior by setting this system variable to zero in your MySQL config.
source: Configuring session timeouts
I receive following output:
Traceback (most recent call last):
File "/home/ec2-user/env/lib64/python3.7/site-packages/redis/connection.py", line 1192, in get_connection
raise ConnectionError('Connection has data')
redis.exceptions.ConnectionError: Connection has data
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/home/ec2-user/env/lib64/python3.7/site-packages/eventlet/hubs/hub.py", line 457, in fire_timers
timer()
File "/home/ec2-user/env/lib64/python3.7/site-packages/eventlet/hubs/timer.py", line 58, in __call__
cb(*args, **kw)
File "/home/ec2-user/env/lib64/python3.7/site-packages/eventlet/greenthread.py", line 214, in main
result = function(*args, **kwargs)
File "crawler.py", line 53, in fetch_listing
url = dequeue_url()
File "/home/ec2-user/WebCrawler/helpers.py", line 109, in dequeue_url
return redis.spop("listing_url_queue")
File "/home/ec2-user/env/lib64/python3.7/site-packages/redis/client.py", line 2255, in spop
return self.execute_command('SPOP', name, *args)
File "/home/ec2-user/env/lib64/python3.7/site-packages/redis/client.py", line 875, in execute_command
conn = self.connection or pool.get_connection(command_name, **options)
File "/home/ec2-user/env/lib64/python3.7/site-packages/redis/connection.py", line 1197, in get_connection
raise ConnectionError('Connection not ready')
redis.exceptions.ConnectionError: Connection not ready
I couldn't find any issue related to this particular error. I emptied/flushed all redis databases, so there should be no data there. I assume it has something to do with eventlet and patching. But even when I put following code right at the beginning of the file, the error appears.
import eventlet
eventlet.monkey_path()
What does this error mean?
Finally, I came up with the answer to my problem.
When connecting to redis with python, I specified the database with the number 0.
redis = redis.Redis(host=example.com, port=6379, db=0)
After changing the dabase to number 1 it worked.
redis = redis.Redis(host=example.com, port=6379, db=1)
Another way is to set protected_mode to no in etc\redis\redis.conf. Recommended when running redis locally.
I am following the installation steps mentioned below but have encountered a python problem.
https://en.wikibooks.org/wiki/GNU_Health/Installation#Installing_GNU_Health_on_GNU/Linux_and_FreeBSD
At the step where the initialisation of the database instance is to be performed, I have encountered the following error after executing the following command.
python3 ./trytond-admin --all --database=health
Error encountered:
Traceback (most recent call last):
File "./trytond-admin", line 21, in <module>
admin.run(options)
File "/home/gnuhealth/gnuhealth/tryton/server/trytond-4.6.18/trytond/admin.py", line 24, in run
with Transaction().start(db_name, 0, _nocache=True):
File "/home/gnuhealth/gnuhealth/tryton/server/trytond-4.6.18/trytond/transaction.py", line 88, in start
database = Database(database_name).connect()
File "/home/gnuhealth/gnuhealth/tryton/server/trytond-4.6.18/trytond/backend/postgresql/database.py", line 97, in __new__
**cls._connection_params(name))
File "/home/gnuhealth/.local/lib/python3.6/site-packages/psycopg2/pool.py", line 161, in __init__
self, minconn, maxconn, *args, **kwargs)
File "/home/gnuhealth/.local/lib/python3.6/site-packages/psycopg2/pool.py", line 58, in __init__
self._connect()
File "/home/gnuhealth/.local/lib/python3.6/site-packages/psycopg2/pool.py", line 62, in _connect
conn = psycopg2.connect(*self._args, **self._kwargs)
File "/home/gnuhealth/.local/lib/python3.6/site-packages/psycopg2/__init__.py", line 126, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
psycopg2.OperationalError: fe_sendauth: no password supplied
Can anyone help me out with this error or tell me what I am missing?
Based on the error, I suspect that there's a difficulty in connecting to the DB as there is no password specified.
It seems that you did not configured the URI with the credentials to connect to the database. You can find the description of the configuration file at http://docs.tryton.org/projects/server/en/latest/topics/configuration.html#uri
Once you have a configuration file, you must run the command like this:
python3 ./trytond-admin --all --database=health -c /path/to/trytond.conf
I am new to neo4j world. I have successfully used it on my macbook. Now I am deploying it on a remote Linux machine with the same setup. But I keep getting this Protocol error. What caused this issue? How to fix this? I have been banging my head on this error for days.
Traceback (most recent call last):
File "/root/dev/knowledgeGraphH/knowledge/media_entity_mapper.py", line 31, in <module>
main()
File "/root/dev/knowledgeGraphH/knowledge/media_entity_mapper.py", line 28, in main
map_media_to_entities()
File "/root/dev/knowledgeGraphH/knowledge/media_entity_mapper.py", line 7, in map_media_to_entities
data_manager = DataManager()
File "/root/dev/knowledgeGraphH/knowledge/data_manager/data_manager.py", line 13, in __init__
self.graphDB = Neo4jManager()
File "/root/dev/knowledgeGraphH/knowledge/neo4j_manager.py", line 10, in __init__
self.session = self.driver.session()
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/session.py", line 148, in session
session = Session(self)
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/session.py", line 461, in __init__
self.connection = connect(driver.host, driver.port, driver.ssl_context, **driver.config)
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/connection.py", line 465, in connect
return Connection(s, der_encoded_server_certificate=der_encoded_server_certificate, **config)
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/connection.py", line 237, in __init__
self.fetch()
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/connection.py", line 326, in fetch
self.acknowledge_failure()
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/connection.py", line 273, in acknowledge_failure
fetch()
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/connection.py", line 311, in fetch
raw.writelines(self.channel.chunk_reader())
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/connection.py", line 169, in chunk_reader
chunk_header = self._recv(2)
File "/root/dev/knowledgeGraphH/env/lib/python2.7/site-packages/neo4j/v1/connection.py", line 152, in _recv
raise ProtocolError("Server closed connection")
neo4j.v1.exceptions.ProtocolError: Server closed connection
Seems to be port issue. Is the bolt port open or not? You have access to the port or not?
Check the output of the following command:
lsof -i tcp:7687
change the port number if you have changed bolt port address.
It turns out it was because I used the wrong credentials for this connection.
I am using django-1.2 and python-2.6 and I am using mysql server.
After working for a while - selecting and updating records, I got this error:
Exception in thread Thread-269:
Traceback (most recent call last):
File "/usr/lib64/python2.6/threading.py", line 532, in __bootstrap_inner
File "dispatcher.py", line 42, in run
File "/usr/lib/python2.6/site-packages/django/db/models/query.py", line 80, in __len__
File "/usr/lib/python2.6/site-packages/django/db/models/query.py", line 271, in iterator
File "/usr/lib/python2.6/site-packages/django/db/models/sql/compiler.py", line 677, in results_iter
File "/usr/lib/python2.6/site-packages/django/db/models/sql/compiler.py", line 731, in execute_sql
File "/usr/lib/python2.6/site-packages/django/db/backends/__init__.py", line 75, in cursor
File "/usr/lib/python2.6/site-packages/django/db/backends/mysql/base.py", line 297, in _cursor
File "/usr/lib64/python2.6/site-packages/MySQLdb/__init__.py", line 81, in Connect
File "/usr/lib64/python2.6/site-packages/MySQLdb/connections.py", line 187, in __init__
OperationalError: (2001, "Can't create UNIX socket (24)")
here are lines 41,42 of my dispatcher.py:
dataList = Mydata.objects.filter(date__isnull=True)[:chunkSize]
print '%s - DB worker finished reading %s entrys' % (datetime.now(),len(dataList))
Any clue why I get this error?
I tried googling but could not find an answer.
I am connecting to the db using django - (I am using localhost)
On my machine, errno==24 is defined like
#define EMFILE 24 /* Too many open files */
Which means you are running out of filedescriptors. Your app is "leaking" filedescriptors by opening them (and not closing them) again and again.
Maybe you're not forgetting to close file. But have too many files opened at the same time.