On Wed, Sep 5, 2018 at 7:19 PM, Connor <connor...@gmail.com> wrote:
> Hi guys,
>
> I'm starting to use association proxies for the first time and I've come
> across an issue that has me stumped.
>
> Basically, I want to use the association proxy's "creator" argument in order
> to create the intermediate object.
> The intermediate object has foreign keys that point to the primary class
> (the one with the AP) and another 3rd class.
> So when creating that intermediate object, I want to be able to point to
> data within the primary objects instance (I need something for the FK column
> to point to!)
>
> This is what I'm trying to do in code:
> chars = association_proxy('char_links', 'char', creator=lambda c:
> CharLink(word_id=self.id, char_id=c.id))
>normally you are using associationproxy with relationships so you don't need to set foreign key attributes directly. Assuming "char_links" and "char" are relationships there is no need to set those attributes, they will be set for you. > But obviously it doesn't work, because my uninstantiated class definition > doesn't know what 'self' is. > This seems like something I should be able to do, as the creator function is > only ever going to be called from an instance of my model (not just the > class definition), so I should have access to the instance's props, no? > > I've found this StackOverflow question that seems to be having the same > problem, but the only answer seems hacky and to be honest I don't really > understand it. > > Any tips? > > ~Connor > > > -- > SQLAlchemy - > The Python SQL Toolkit and Object Relational Mapper > > http://www.sqlalchemy.org/ > > To post example code, please provide an MCVE: Minimal, Complete, and > Verifiable Example. See http://stackoverflow.com/help/mcve for a full > description. > --- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sqlalchemy+unsubscr...@googlegroups.com. > To post to this group, send email to sqlalchemy@googlegroups.com. > Visit this group at https://groups.google.com/group/sqlalchemy. > For more options, visit https://groups.google.com/d/optout. -- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
