Sails.js模型:创建2个自我失败的关联

Question

我在Nodejs和sails上都很新.我正在实现一个类似于Twitter的服务器.在用户模型中,应该有2个字段:跟随者和跟随者,并且2个字段是模型"用户"本身的关联.

我的问题是当模型只有1个关联时,无论是跟随者还是跟随者,它都有效.但是,如果包括跟随者和跟随者,则会出现错误.

代码是这样的:

module.exports = {
   attributes: {
   alias: {
     type:'string',
     required: true,
     primaryKey: true
   },
   pwd: {
    type: 'string',
    required: true
   },
   follower: {
      collection: 'user',
      via: 'alias'
   },
   following:{
      collection: 'user',
      via: 'alias'
   }
}

代码会导致这样的错误:

    usr/local/lib/node_modules/sails/node_modules/waterline/node_modules/waterline-schema/lib/waterline-schema/references.js:115
throw new Error('Trying to associate a collection attribute to a model tha
      ^
Error: Trying to associate a collection attribute to a model that doesn't have a Foreign Key. user is trying to reference a foreign key in user
at References.findReference (/usr/local/lib/node_modules/sails/node_modules/waterline/node_modules/waterline-schema/lib/waterline-schema/references.js:115:11)
at References.addKeys (/usr/local/lib/node_modules/sails/node_modules/waterline/node_modules/waterline-schema/lib/waterline-schema/references.js:72:22)

Answer 1

对于这种用法，您的模型定义（即关键字）不正确via。根据水线关联文档，关键字via引用了关联的另一侧。所以，对于 a 来说follower另一边是following，反之亦然。换句话说：

follower: {
  collection: 'user',
  via: 'following'
},
following:{
  collection: 'user',
  via: 'follower'
}

您可以在以下位置查看完整的工作示例：https://github.com/appscot/sails-orientdb/blob/master/test/integration-orientdb/tests/associations/manyToMany.selfReferencing.js