On Aug 9, 2010, at 5:12 PM, flzz wrote: > Greetings, I have an object model which I'm persisting with > SQLAlchemy (0.6.3). I have a need for one of the objects in the model > to always merge itself into the session when a new instance is added. > For example, given > > sub = Subscription(email=EmailAddress(value='f...@bar.com)) > > which will then be added to the model via a dynaimc_loader backed by > an AppenderQuery > > model.lists[0].subscriptions.append(sub) > > Given the EmailAddress model enforces uniqueness of the value, I want > the EmailAddress instance to merge itself into the session without me > having to manually query for it.
If I'm understanding correctly, that's not as much about merging as it is for the "unique object" recipe, which is this: http://www.sqlalchemy.org/trac/wiki/UsageRecipes/UniqueObject which assumes the usage of a scoped_session. Since you're looking for the callable EmailAddress to know about a session and you don't want to pass it in, there's not really any other option. > > So far I've explored a SessionExtension and manually passing the > session into the constructor using a trick I found while searching > around on this group: > > sub = Subscription(email=EmailAddress(session=session, > value='f...@bar.com)) > > This does exactly what I want it to but is less than desirable from a > usability perspective. I've had no luck with a SessionExtension. Any > recommendations? > > Thanks! > > -- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To post to this group, send email to sqlalch...@googlegroups.com. > To unsubscribe from this group, send email to > sqlalchemy+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/sqlalchemy?hl=en. > -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalch...@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.
