重新排序[ES6]单独的文件循环引用

Question

有两个文件，一个叫做

customer.model.js

import DbContext from '../databaseContext'
import Sequelize from 'sequelize'
import LeaseModel from './lease.model';

const CustomerModel = DbContext.define('customer', {
  first_name: {
    type: Sequelize.STRING(50)
  },
  middle_name: {
    type: Sequelize.STRING
  },
  last_name: {
    type: Sequelize.STRING(50)
  },
  email: {
    type: Sequelize.STRING(62)
  }
})

CustomerModel.hasMany(LeaseModel)


export default CustomerModel

lease.model.js

import Sequelize from 'sequelize'

const LeaseModel = DbContext.define('lease', {
  lease_name: {
    type: Sequelize.STRING(50)
  },
  customer_id: {
    type: Sequelize.IndexHints
  }
})

export default LeaseModel

如果我在lease.model.js中添加下面的Lease.belongsTo(CustomerModel)来表示外键关系，我将得到循环引用，那么解决这个问题的好方法是什么？

Answer 1

Sequelize过去有一个名为import的方法。您可以在那里导入模型并将每个模型连接到它的构造函数中。

Answer 2

创建一个index.js文件。导入此文件中的所有模型并将它们关联起来。在此之后，再出口这些型号。

例如。

models/customer.model.js

import DbContext from '../databaseContext'
import Sequelize from 'sequelize'

const CustomerModel = DbContext.define('customer', {
  first_name: {
    type: Sequelize.STRING(50)
  },
  middle_name: {
    type: Sequelize.STRING
  },
  last_name: {
    type: Sequelize.STRING(50)
  },
  email: {
    type: Sequelize.STRING(62)
  }
});

export default CustomerModel;

models/lease.model.js

import Sequelize from 'sequelize'
import DbContext from '../databaseContext'

const LeaseModel = DbContext.define('lease', {
  lease_name: {
    type: Sequelize.STRING(50)
  },
  customer_id: {
    type: Sequelize.IndexHints
  }
})

export default LeaseModel

models/index.js

import CustomerModel from './customer.model'
import LeaseModel from './lease.model';
// import other models...

CustomerModel.hasMany(LeaseModel);
LeaseModel.belongsTo(CustomerModel);
// associate other models...

export {CustomerModel, LeaseModel}