Saturday, May 21, 2005

Creating an ODBC data source using Python

For the cross-platform installer I am creating, I need to create ODBC data sources for Windows installations. Thanks to the Python ctypes module the solution was as simple as:

import ctypes

ODBC_ADD_DSN = 1 # Add data source
ODBC_CONFIG_DSN = 2 # Configure (edit) data source
ODBC_REMOVE_DSN = 3 # Remove data source
ODBC_ADD_SYS_DSN = 4 # add a system DSN
ODBC_CONFIG_SYS_DSN = 5 # Configure a system DSN
ODBC_REMOVE_SYS_DSN = 6 # remove a system DSN

def create_sys_dsn(driver, **kw):
"""Create a system DSN
driver - ODBC driver name
kw - Driver attributes
0 - DSN not created
1 - DSN created
nul = chr(0)
attributes = []
for attr in kw.keys():
attributes.append("%s=%s" % (attr, kw[attr]))

return ctypes.windll.ODBCCP32.SQLConfigDataSource(0, ODBC_ADD_SYS_DSN, driver, nul.join(attributes))

if __name__ == "__main__":
print create_sys_dsn("SQL Server",SERVER="(local)", DESCRIPTION="SQL Server DSN", DSN="SQL SERVER DSN", Database="mydatabase", Trusted_Connection="Yes")
print create_sys_dsn("mySQL",SERVER="local", DESCRIPTION="mySQL Server Test1", DSN="mySQL DSN", DATABASE="mySQLDb", UID="username", PASSWORD="password", PORT="3306", OPTION="3")

Require a cross-platform installer, Python to the rescue

The company I work for develops an ERP system that has it's heritage in implementations for medium size companies running on UNIX systems. As the global ERP vendors have moved in our space, we have had to move into the SME market which means running on Linux or Windows server systems. And since some of our new clients cannot afford the cost of a technical resource going on-site to install and configure the technical infrastructure, we need a cross-platform installer. As our application is not written in Java, we are not interested in a Java based installer. But since our supporting scripts are written in Python, and I have had some success creating a cross-platform installer in Python to install and build the the required 3rd party packages for Python Paste, I decided Python could provide a solution. Currently a work in progress, I have a Python script that installs our complete ERP app, it's supporting runtimes and configures it to run in under 10 minutes. Still need to get database setup working, and as our app can run under Oracle, IBM Informix or MS SQL Server 2000 there is abit of work to be done.

Of course to make it look like a "real" installer under Windows I use Inno Setup, and call an executable version of the python script created by py2exe. Rather try trying to write in Delphi to get custom forms for the installor I used ctypes and the Windows port of EasyDialogs to collect site specific setup data. So thanks to the hard work of the creators of the various tools I have used and Python, it looks like we will have our cross-platform installer.