Showing posts with label mysql-python. Show all posts
Showing posts with label mysql-python. Show all posts

Friday, July 09, 2010

Installing MySQL-python (MySQLdb) in a virtualenv on OSX 10.6

There were two problems with the MySQL-Python package that I had when installing on OS X 10.6
1) First, an error saying "EnvironmentError: mysql_config not found" when setup.py is run (through pip or easy_install)
2) Second, an error saying "ImportError: dynamic module does not define init function(init_mysql) when importing MySQLdb" when 'import MySQLdb" is issued

Causes:
1) This is caused by the build script not being able to find a MySQL program called mysql_config. This program is used to determine metadata about the mysql install. For example, the command "mysql_config --cflags" reports the flags used to build mysql.
2) This is caused by a mismatch between the architectures that MySQL was built with and the architecture that MySQL-python installer is trying to build and install MySQL-python as. To find what arch MySQL was built as, run
"mysql_config --cflags" (this was i386 in my case). OSX tries to build MySQL-python as x86_64. Therefore, there is a arch mismatch.

Solution:
1) Locate the mysql_config binary location and add the path to the MySQL-python/site.cfg file as a config directive: "mysql_config = /opt/local/bin/mysql_config5"
2) Use the arch x86_64 (64 bit) version of MySQL compiled through MacPorts, not a i386 (32 bit) version downloaded off the internet and installed as a dmg.

Summary:
Assuming the MacPorts version of MySQL is installed, both issues can be solved by adding the mysql_config = /opt/local/bin/mysql_config5 config directive to the MySQL-python/site.cfg file.

# SCRIPTED SOLUTION: Create a script called setup.sh and add the following lines
virtualenv --distribute --no-site-packages ve
source ./ve/bin/activate
pip install -E ./ve -r requirements.1.pip # other deps
export ARCHFLAGS="-arch x86_64"
pip install -E ./ve MySQL-python
echo "mysql_config = /opt/local/bin/mysql_config5" >> ./ve/build/MySQL-python/site.cfg
pip install -E ./ve MySQL-python


Resources:
http://groups.google.com/group/python-virtualenv/msg/cf4f3117faea476b?pli=1
http://birdhouse.org/blog/2009/02/21/python-mysql-connections-on-mac-os/
http://stackoverflow.com/questions/2111283/how-to-build-64-bit-python-on-os-x-10-6-only-64-bit-no-universal-nonsense