(Updated for ember-data API Rev 11...)

TL;DR

What is the right way to use DS.Adapter.findAssociation(...)DS.Adapter.findHasMany(...) to load hasMany associations on demand? Especially, once you load child records, how do you deal with the fact that re-loading the parent record from the server empties the hasMany array? I do not want to (perhaps can't) include the id's of the child records in an array in the parent. Or is there another way to do this that I'm missing?

As a side note, I'm confused about what options should be passed in a hasMany/belongsTo definition for key linkage (and am I supposed to use mappings if I have no sideloaded data or array of ids?), so if you think my problem could lie in my association definition, there's a good chance you're right.

Long version

I am writing my own subclass of DS.RESTAdapter to tie ember-data to an ASP.NET WebAPI backend (using Entity Framework). So far so good, but I'm having a heck of a time getting associations to work right.

Similar to this poster, I noticed that ember-data's front page says used to say that if you have a hasMany association in your model, and you get that property, the store will issue a request for the child records. Quoting from the page:

If you were to request the profile, like this:

author.get('profile');

…the REST adapter would send a request to the URL /profiles?author_id=1.

The implication is this is what happens if you don't sideload and don't include an array of ids. I realize that these docs are somewhat out of date, but I haven't been able to make this happen, either in API version 7 or more recen