Cascade unloading

[buschtoens]

If I unload a Human I would expect its Legs to be unloaded as well, since they cannot exist without their corresponding Human.

This isn't currently possible by only using an Adapter mixin. Do you have some alternative ideas?

[buschtoens]

I suggest switching to decorators and then relying on the didDelete event and overwriting the unloadRecord method.

// app/models/human.js
import Model from 'ember-data/model';
import attr from 'ember-data/attr';
import { hasMany, belongsTo } from 'ember-data/relationships';
import { cascadeDelete, cascadeUnload } from 'ember-data-cascade-delete';

export default Model.extend({
  name: attr('string'),

  @cascadeUnload
  @cascadeDelete
  heart: belongsTo('heart', { async: true, inverse: 'human' }),

  @cascadeUnload
  @cascadeDelete
  legs: hasMany('leg', { async: true, inverse: 'human' })
});

[buschtoens]

Using the above pattern, you could even walk the extra mile and make sure that when a relationship is cleared, the orphaned child record gets deleted / unloaded.

[miguelcobain]

For the record, 2 years after, I now think that this shouldn't be a decorator, but an option of belongsTo/hasMany like it always was.

Here is how it looks nowadays:

// app/models/human.js
import Model, { attr, belongsTo, hasMany } from '@ember-data/model';

export default class Human extends Model {
  @attr('string')
  name;

  @belongsTo('heart', { async: true, inverse: 'human', cascadeDelete: true })
  heart;

  @hasMany('leg', { async: true, inverse: 'human', cascadeDelete: true })
  legs;
}

The reason is that this is still describing a relationship.

Cascade unloading is still desirable and it would be nice if we could not use mixins.