transform

import Transform from '@ember-data/serializer/transform';
import { tracked } from "@glimmer/tracking";

class MyAggregateClass {
  @tracked a;
  @tracked b;

  constructor({ a, b } = {}) {
    this.a = a;
    this.b = b;
  }

  get c() {
    const { a, b } = this;

    return (a && b) ? a + b : 1;
  }
}

export default class AggregateTransform extends Transform {
  deserialize(attrValObj) {

    return new MyAggregateClass(attrValObj);
  }

  serialize(deserialized) {
    return deserialized;
  }
}


export default class MyModel extends Model {
  @attr("aggregate") fields;
}