Ember 数据 - 无法读取未定义的属性“typeKey”

Question

尝试将plan 模型嵌入加载到我的app 模型中。

我在加载时不断收到以下错误（它保存得很好）：

Cannot read property 'typeKey' of undefined TypeError: Cannot read property 'typeKey' of undefined
at Ember.Object.extend.modelFor (http://localhost:4200/assets/vendor.js:71051:22)
at Ember.Object.extend.recordForId (http://localhost:4200/assets/vendor.js:70496:21)
at deserializeRecordId (http://localhost:4200/assets/vendor.js:71500:27)
at http://localhost:4200/assets/vendor.js:71477:11
at http://localhost:4200/assets/vendor.js:69701:20
at http://localhost:4200/assets/vendor.js:17687:20
at Object.OrderedSet.forEach (http://localhost:4200/assets/vendor.js:17530:14)
at Object.Map.forEach (http://localhost:4200/assets/vendor.js:17685:14)
at Function.Model.reopenClass.eachRelationship (http://localhost:4200/assets/vendor.js:69700:42)
at normalizeRelationships (http://localhost:4200/assets/vendor.js:71463:12) vendor.js:17062logToConsole

---

话虽如此，我有以下型号，

app/models/app.js

export default DS.Model.extend({
  name:    attribute('string'),
  domain:  attribute('string'),
  plan:    DS.belongsTo('plan', { embedded: 'load' }),
  creator: DS.belongsTo('user', { async: true }),

  time_stamp: attribute('string', {
    defaultValue: function () {
       return moment().format("YYYY/MM/DD HH:mm:ss");
    }
  })
});

app/models/plan.js

export default DS.Model.extend({
  price:       attribute('number'),
  description: attribute('string'),
  tagline:     attribute('string'),
  title:       attribute('string'),
  features:    attribute('array') // Array is defined in a transform, don't worry.
});

计划成为一种静态文档。

这是我调用store.get('creator.apps');时的服务器响应

{
  "apps":[
    {
      "_id":"53da9994b2878d0000a2e68f",
      "name":"Myapp",
      "domain":"http://myapp.com",
      "creator":"53d9598bb25244e9b1a72e53",
      "plan":{
        "_id":"53d93c44b760612f9d07c921",
        "price":0,
        "description":"Free plan",
        "tagline":"Great for testing",
        "title":"Developer",
        "features":["5,000 Requests","API/Plugin Access"],
        "__v":0
      },
      "time_stamp":"2014/07/31 13:31:32",
      "__v":0
    }
  ]
}

我意识到 typeKey 错误是由于 Ember 没有找到响应模型。我可以确认它找到了应用类型，在 normalizeHash.apps 下触发了一个钩子。

抱歉，这篇文章太长了，我无法理解问题的原因！

Answer 1

App.Thing = DS.Model.extend(
    {
        name: attr('string'),
        children: DS.hasMany('child', {inverse:null})
    }
);

App.ThingSerializer = DS.RESTSerializer.extend(
    DS.EmbeddedRecordsMixin, {
        attrs: {
            children: { embedded: 'always' }
        }
    }
);

DS.EmbeddedRecordsMixin 必须在您的模型中，并且您必须具有 `embedded:'always' 以获得正确的属性。

如果您有 Thing 模型，那么您可以使用特定于模型的序列化程序让 Ember Data 加载嵌入的子项（此处为嵌套对象数组）。

资源：

• http://emberjs.com/guides/models/customizing-adapters/
• http://emberjs.com/api/data/classes/DS.EmbeddedRecordsMixin.html

Answer 2

Ember 不希望将记录嵌入到父记录的 JSON 中。 做你需要做的，让你的json像这样。仅包含计划 ID。

{
  "apps":[
    {
      "_id":"53da9994b2878d0000a2e68f",
      "name":"Myapp",
      "domain":"http://myapp.com",
      "creator":"53d9598bb25244e9b1a72e53",
      "plan_id":"53d93c44b760612f9d07c921",    // just output id only not embedded record 
      "time_stamp":"2014/07/31 13:31:32",
      "__v":0
    }
  ]
}

然后让 ember 使用 async: true 查找相关模型本身

export default DS.Model.extend({
  name:    attribute('string'),
  domain:  attribute('string'),
  plan:    DS.belongsTo('plan', { async: true }),     //changed
  creator: DS.belongsTo('user', { async: true }),

  time_stamp: attribute('string', {
    defaultValue: function () {
       return moment().format("YYYY/MM/DD HH:mm:ss");
    }
  })

});

我自己刚刚经历了这个痛苦，并在一些帮助下找到了答案。

对于其他来到这里但仍然有问题的人，请阅读我对我自己的问题的回答，详细了解 typeKey 错误的含义以及我自己用来解决问题的进一步步骤。

Deploying ember-rails to Heroku - TypeError: Cannot read property 'typeKey' of undefined