hasMany, belongsTo inconsistent about adapter vs serializer

[jamesarosen]

Summary

In a hasMany or belongsTo relationship, fetching the associated record(s) will use the source adapter and the foreign serializer.

Example

I have two models: Person and Group:

// app/models/group.js:
people: DS.hasMany('person')

// app/models/person.js:
group: DS.belongsTo('group')

The Person API is classic JSON. The Group API is JSON-API. So I declare adapters and serializers accordingly:

// app/adapters/group.js
import DS from 'ember-data';
export default DS.JSONAPIAdapter;

// app/adapters/person.js
import ActiveModelAdapter from 'active-model-adapter';
export default ActiveModelAdapter;

// app/serializers/group.js
import DS from 'ember-data';
export default DS.JSONAPISerializer;

// app/serializers/person.js
import { ActiveModelSerializer } from 'active-model-adapter';
export default ActiveModelSerializer;

If I do a store.findAll('person') or a store.find('group', 178), this works great.

But if I do person.get('group') or group.get('people'), this breaks terribly. The problem is that person.get('group') uses adapter:person (not adapter:group), but serializer:group. Thus, it's receiving active-model-style JSON, but expecting JSON-API.

If I do store.query('group', { include: 'people' }), it breaks in a different way. The JSON-API response for groups comes back with JSON-API documents for the people. It passes these documents to serizlier:person, which expects active-model-style JSON documents.