LoopBack/Node.js查询中的多个包含不同深度的对象 [英] Multiple includes on different depths in a LoopBack/Node.js query

问题描述

我正在尝试在node.js环回服务器上加载一个对象，并且想在同一查询中加载多个相关对象.这些相关对象位于不同的深度.这是查询:

I'm trying to load an object on a node.js Loopback server and I want to load multiple related objects in the same query. These related objects are on different depths. This is the query:

/api/MyUsers/114?filter[include][institutes]=institute&filter[include]=departments&filter[include]=profiles

请注意， [institutes] = institute 有两个级别，而部门和个人资料只有一个级别.

Notice that [institutes]=institute have two levels and departments and profiles only one.

这给我返回一个错误: 500内部服务器错误.错误:未为用户模型定义关系"0".

This returns me an error: 500 Internal server error. Error: Relation "0" is not defined for User model.

在node.js调试中，我注意到生成的最终JSON查询似乎是错误的:

On node.js debug I noticed that the final JSON query generated seems to be wrong:

{ include: 
     { '0': 'departments',
       '1': 'profiles',
       institutes: 'institute' } },
     ...
}

这是MyUser的模型:

Here is the model for MyUser:

{
  "name": "MyUser",
  "plural": "MyUsers",
  "base": "User",
  "idInjection": true,
  "options": {
    "validateUpsert": true
  },
  "mixins": {
    "Versioning": true,
    "Tenant": true
  },
  "properties": {
    "name": {
      "type": "string",
      "required": true
    },
    "email": {
      "type": "string"
    }
  }
  "validations": [],
  "relations": {
    "departments": {
      "type": "hasMany",
      "model": "UserDepartment",
      "foreignKey": "user_id"
    },
    "institutes": {
      "type": "hasMany",
      "model": "UserInstitute",
      "foreignKey": "user_id"
    },
    "profiles": {
      "type": "hasMany",
      "model": "UserProfile",
      "foreignKey": "user_id"
    },
  },
  "acls": [],
  "methods": {}
}

还有其他人遇到过这个问题吗?它是回送错误吗?如果是这样，我该如何解决?

Has anyone else faced this problem? Is it a loopback bug? If so, how can I turn around for a solution?

推荐答案

500内部服务器错误.错误:未为用户模型定义关系"0".

此错误表明您的用户模型没有称为部门的关系.在用户模型的定义中，确保已为部门模型添加了关系. (顺便说一句，如果departaments是英语单词，则存在拼写问题，departments是正确的.)

This error says that your User model does not have a relation which is called departaments. In your definition of the User model, make sure that you added a relation for the departaments model. (By the way, if departaments is an English word, it has a spelling problem, departments is correct.)

链接表示:

通过包含过滤器，您可以包含来自相关模型的结果 在查询中，例如，具有belongsTo或hasMany的模型 关系，以优化请求数.

An include filter enables you to include results from related models in a query, for example, models that have belongsTo or hasMany relations, to optimize the number of requests.

此链接可以帮助您定义模型的关系:

This link can help you to define a relation for your model:

https://strongloop. com/strongblog/定义和映射数据关系-具有环回连接模型/

如果您使用内置的用户模型，则可以按照以下链接扩展它:

If you are using the built-in User model, you can extend it as below link says:

https://loopback.io/doc/en /lb3/Extending-built-in-models.html

评论后

关于过滤器的另一种解释:

One more explanation about filters:

filter [include] [institutes] = institute过滤器的含义是:

The meaning of filter[include][institutes]=institute filter is:

包括作为用户关系的机构"，还包括作为机构"的关系的机构". 我在我的一个项目中测试了此功能，效果很好.

Include 'institutes' which is a relation of User and also include 'institute' which is a relation of 'institutes'. I tested this feature in one of my projects and it works fine.

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