cx_Oracle running with mod_wsgi environment - apache

Question

I installed cx_Oracle on CentOS 6.2. When I import the library from the shell, it works fine but when I launch it through wsgi, I get the error :
ImportError: libclntsh.so.10.1: cannot open shared object file: No such file or directory
This is an environment variable problem : cx_Oracle does not find the path to the lib.
I have tried the solutions provided here
I have added a link to libclntsh.so.10.1 (with ln) in the /usr/lib directory
I have edited apache configuration and added :
ORACLE_HOME=/usr/lib/oracle/11.2/client64/lib
LD_LIBRARY_PATH=$ORACLE_HOME/
PATH=$ORACLE_HOME/bin:$PATH
I edited /etc/ld.so.conf and added :
/usr/lib/oracle/11.2/client64/lib
done after ldconfig
I tried to use python with :
os.env['ORACLE_HOME']='/usr/lib/oracle/11.2/client64/lib'
I edited the bashrc with :
export ORACLE_HOME=/usr/lib/oracle/11.2/client64/lib
export LD_LIBRARY_PATH=$ORACLE_HOME/
export PATH=$ORACLE_HOME/bin:$PATH
I also edited apachectl with
ORACLE_HOME=/usr/lib/oracle/11.2/client64/lib
export ORACLE_HOME
LD_LIBRARY_PATH=$ORACLE_HOME/
export LD_LIBRARY_PATH
PATH=$ORACLE_HOME/bin:$PATH
export PATH
I am running out of ideas. Any suggestions ?

Answer 1

When you compile the Python module for Oracle, set:
LD_RUN_PATH=/usr/lib/oracle/11.2/client64/lib
user environment variable and export it. This will cause that directory to be embedded in Python extension module .so file and will know where to find it at run time without needing to set LD_LIBRARY_PATH environment variable.
For a standard Apache distribution (Linux distros are often a bit different), the file to set extra environment variables in is called 'envvars' and is in same directory as 'httpd'. For Linux distros often needs to be in a special init.d startup script.
So, lookup what LD_RUN_PATH is all about.

Answer 2

Instead of using yum install on the cx_Oracle rpm, I downloaded the source of the library and run the setup.py build.
I got an error that would point me to the function that was trying to locate the instant client sdk libraries in :
possibleIncludeDirs = ["rdbms/demo", "rdbms/public", "network/public","sdk/include"]
Browsing the Oracle_home folder, i discovered that the sdk file where installed in the lib folder ( I installed the skd using yum install on the rpm from oracle ) and not in the possibleIncludeDirs or in an include folder as suggested in the setup.py :
if not includeDirs:
path = os.path.join(oracleLibDir, "include")
if os.path.isdir(path):
includeDirs.append(path)
if not includeDirs:
path = re.sub("lib(64)?", "include", oracleHome)
if os.path.isdir(path):
includeDirs.append(path)
I downloaded the instant client sdk (the zip file this time) and unziped it to the lib folder.
There was then a sdk folder in the lib folder (/usr/lib/oracle/11.2/client64/lib)
I then launched the setup.py build and setup.py install and it worked.