How to fix: cx_Oracle.DatabaseError: ORA-12578: TNS:wallet open failed

Question

I am establishing connection to Oracle database in Python using cx_Oracle. I am using wallet to connect to DB. And the code is running inside virtual env. When I activate the virtual env and run the script manually, it runs fine. But it throws below error when running form crontab or Tidal (a scheduler):

cx_Oracle.DatabaseError: ORA-12578: TNS:wallet open failed

Previously I was facing another similar issue:

cx_Oracle.DatabaseError: DPI-1047: Cannot locate a 64-bit Oracle Client library: "libclntsh.so"

-working fine with manual run but gives error with crontab, which was resolved by including the suggested line from this answer.

Below is the cronjob:

0 6 * * * cd /path/to/the/code && /path/to/the/venv/myEnv/bin/python /path/script.py 

Below is the code:

#!/usr/bin/env python3

import os
import cx_Oracle

os.environ["ORACLE_HOME"]="/u01/app/oracle/product/12.2.0/client64"

def fetch_data():
    #connection = cx_Oracle.connect("user", "pwd", "conn")
    connection = cx_Oracle.connect(dsn="WALLET_NAME", encoding="UTF-8")
    cursor = connection.cursor()
    with open('rtp_query.sql') as f:
        sql = f.read()
    cursor.execute(sql)
    result = cursor.fetchall()
    cursor.close()
    connection.close()

Note that username/pwd connection is working from both command line and crontab, but with Wallet string, it only works from command line, and throws below error for crontab:

cx_Oracle.DatabaseError: ORA-12578: TNS:wallet open failed

Answer 1

what helped on our end was to broaden permissions on the oracle wallet files. Locate your oracle wallet files and do 'chmod 750 *wallet*' so that other users of the same user group can read the files.