Ember 不保留 belongsTo 数据

Question

我正在使用 Ember 2.4.6 和 Ember 的 JSONApiAdapter 来获取数据并将数据发送到节点服务器。

我有以下标签模型：

import DS from 'ember-data';

export default DS.Model.extend({
  label: DS.attr('string'),
  isRoot: DS.attr('boolean', {defaultValue: false'}),
  parent: DS.belongsTo('tag') //belongs to self type
});

这里的逻辑是用户可以为给定的根标签输入多个子标签。为了保存子标签和根标签，我使用了标签服务中的保存方法。标签服务的保存方法如下

import Ember from 'ember';

export default Ember.Service.extend({

  //Some other code

  save: function(parent, children){
    return parent.save().then(response => {
      return children.map(tag => {
        tag.set('parent', response);
        return tag.save();
      });
    });
  }
});

现在的问题是，当我为根标签说了五个子标签时，关系只会持续到最后一个标签，即第五个标签。

我为 root 父标签创建了五个标签 one、two、three、four 和 five。然后，当从标记服务调用保存方法时，理想情况下应将以下数据发送到服务器。

{data: {id: 1, type: 'tags', attributes: {label: "root", "is-root": true}, relationships: {parent: {data: null}}}}
{data: {id: 2, type: 'tags', attributes: {label: "one", "is-root": false}, relationships: {parent: {data: {id: 1, type: "tags"}}}}}
{data: {id: 3, type: 'tags', attributes: {label: "two", "is-root": false}, relationships: {parent: {data: {id: 1, type: "tags"}}}}}
{data: {id: 4, type: 'tags', attributes: {label: "three", "is-root": false}, relationships: {parent: {data: {id: 1, type: "tags"}}}}}
{data: {id: 5, type: 'tags', attributes: {label: "four", "is-root": false}, relationships: {parent: {data: {id: 1, type: "tags"}}}}}
{data: {id: 6, type: 'tags', attributes: {label: "five", "is-root": false}, relationships: {parent: {data: {id: 1, type: "tags"}}}}}

而是将以下信息发送到服务器

{data: {id: 1, type: 'tags', attributes: {label: "root", "is-root": true}, relationships: {parent: {data: null}}}}
{data: {id: 2, type: 'tags', attributes: {label: "one", "is-root": false}, relationships: {parent: {data: null}}}}
{data: {id: 3, type: 'tags', attributes: {label: "two", "is-root": false}, relationships: {parent: {data: null}}}}
{data: {id: 4, type: 'tags', attributes: {label: "three", "is-root": false}, relationships: {parent: {data: null}}}}
{data: {id: 5, type: 'tags', attributes: {label: "four", "is-root": false}, relationships: {parent: {data: null}}}}
{data: {id: 6, type: 'tags', attributes: {label: "five", "is-root": false}, relationships: {parent: {data: {id: 1, type: "tags"}}}}}

只为最后一个标签发送 belongsTo 信息，对于所有其他标签，父数据丢失。

无法准确理解为什么会这样。请在这里指出我做错了什么。

Answer 1

在您的标签模型中，试试这个：

import DS from 'ember-data';

export default DS.Model.extend({
  label: DS.attr('string'),
  isRoot: DS.attr('boolean', {defaultValue: false}),
  parent: DS.belongsTo('tag', {inverse: null})
});

您可以在此处获得有关自反关系的更多信息：https://guides.emberjs.com/v2.9.0/models/relationships/#toc_reflexive-relations

来自页面：

When you want to define a reflexive relation (a model that has a relationship to itself), you must explicitly define the inverse relationship. If there is no inverse relationship then you can set the inverse to null.

Ember 不保留 belongsTo 数据

Ember not persisting belongsTo data

javascript

ember.js

ember-data

ember-cli