[Zope-dev] Re: straighting out the SQLAlchemy integration mess

[Martin Aspeli]

Martijn Faassen wrote:
> Andreas Jung wrote:
>> --On 10. April 2008 19:10:49 +0200 Brian Sutherland 
>> <brian at vanguardistas.net> wrote:
>>> Just adding my few requirements:
>>>     - Integration into the component architecture in such a way that I
>>>       can specify the db connection parameters in ZCML and that database
>>>       reflection still works. I want to be able to get a handle on
>>> SQLAlchemy       things by calling getUtility.
>> Please *NO* database specific configurations within ZCML. We're running 
>> applications in up three or four different environments and I don't want 
>> to maintain instance specific configurations within ZCML. Either we pass
>> such informations through environment variables or the database 
>> connections parameters are read from a configuration within the instance 
>> configuration.
> 
> As long as it can also be specified in the code, that way people can 
> build UIs to set up the connection. Perhaps that's what you mean by a 
> "configuration within the instance configuration".

The way I use collective.lead in my book is to have it look up the 
database settings in a local utility. That utility is editable via a 
control panel page in Plone. I suspect that it'd be quite easy to do 
something similar where the settings were deferred to a global utility 
configured with ZCML or looked up in a config file of some sort.

Once the config is available, it's all about calling getUtility() to get 
hold of a database connection/session.

Martin

-- 
Author of `Professional Plone Development`, a book for developers who
want to work with Plone. See http://martinaspeli.net/plone-book