collective.saconnect 2.0

Introduction

This package provides a simple control panel and storage for SQLAlchemy connection strings. It presents a form where one can add and remove named connections, and a GS import and export step to manage these.

This package does not provide SQLAlchemy integration itself; use a library like zope.sqlalchemy, collective.lead or pas.plugins.sqlalchemy instead.

Example usage:

from zope.app.component.hooks import getSite
from collective.saconnect.interfaces import ISQLAlchemyConnectionStrings

saconnect = ISQLAlchemyConnectionStrings(getSite())
myconnection = saconnect['myidentifier']

ISQLAlchemyConnectionStrings acts as a simple dictionary, although it’s keys and values must be simple strings.

To import connection strings through GenericSetup, simply include a file named saconnections.xml in your profile, with a top-level ‘connections’ element and one ‘connection’ element per connection, with name and string attributes:

<?xml version="1.0"?>
<connections>
 <connection name="bar" string="sqlite:////path/to/bar.sqlite"/>
 <connection name="foo" string="oracle://username:password/tnsnamethere"/>
</connections>

To remove any of the connections, use the ‘remove’ attribute:

<?xml version="1.0"?>
<connections>
  <connection name="bar" remove=""/>
</connections>

If you cache your SQLAlchemy connections, you may want to listen for the IObjectModifiedEvent for ISQLAlchemyConnectionStrings. The event includes the key of the modified string, so you can easily refresh your database connections:

<subscriber
    handler=".mymodule.saconnectionUpdated"
    for="collective.saconnect.interfaces.ISQLAlchemyConnectionStrings
         zope.lifecycleevent.interfaces.IObjectModifiedEvent"
/>

def saconnectionUpdated(connections, event):
    if 'myconnectionstring' in event.descriptions:
        getUtility(IDatabase, u'myconnection').invalidate()

Changelog