如何使用feathersjs、sequelize和postgresql创建两个表之间的关系答案

【问题标题】：How to create relationship between two tables using feathersjs, sequelize and postgresql如何使用feathersjs、sequelize和postgresql创建两个表之间的关系
【发布时间】：2022-04-20 23:15:04
【问题描述】：

当我在这两个模型之间创建关系并使用 npm run 运行 feathersjs 时，我有两个模型 users.model.js 和 swing-trades.model.js dev`，我收到一个错误。

抛出新错误(${this.name}.hasMany called with something that's not a subclass of Sequelize.Model); ^

错误：users.hasMany 调用的东西不是续集.模式

**users.model.js**

// See http://docs.sequelizejs.com/en/latest/docs/models-definition/
// for more of what you can do here.
const Sequelize = require('sequelize');
const DataTypes = Sequelize.DataTypes;

module.exports = function (app) {
  const sequelizeClient = app.get('sequelizeClient');
  const users = sequelizeClient.define('users', {

    email: {
      type: DataTypes.STRING,
      allowNull: true,
      unique: true
    },
    password: {
      type: DataTypes.STRING,
      allowNull: true
    },
    username: {
      type: DataTypes.STRING,
      allowNull: true,
    },
    firstName: {
      type: DataTypes.STRING,
      allowNull: true,
    },
    lastName: {
      type: DataTypes.STRING,
      allowNull: true,
    }
  },
  {
    timestamps: true, // Enable timestamps
    createdAt: true, // Don't create createdAt
    updatedAt: true, // Don't create updatedAt
    // eslint-disable-next-line no-dupe-keys
    updatedAt: 'updateTimestamp', // updatedAt should be called updateTimestamp
  },
  {
    hooks: {
      beforeCount(options) {
        options.raw = true;
      }
    }
  });

  // eslint-disable-next-line no-unused-vars
  users.associate = function (models) {
    // Define associations here
    // See http://docs.sequelizejs.com/en/latest/docs/associations/
    const {swingTrades} = models;

    users.hasMany(swingTrades, {as: 'swingTrades', foreignKey: 'userId'}); // will add userid to swingtrades model
  };

  return users;
};

swing-trades.model.js

// See http://docs.sequelizejs.com/en/latest/docs/models-definition/
// for more of what you can do here.
const Sequelize = require('sequelize');
const DataTypes = Sequelize.DataTypes;

module.exports = function (app) {
  const sequelizeClient = app.get('sequelizeClient');
  const swingTrades = sequelizeClient.define('swing_trades', {
    company: {
      type: DataTypes.STRING,
      allowNull: true
    }
  },
  {
    timestamps: true, // Enable timestamps
    createdAt: false, // Don't create createdAt
    updatedAt: false, // Don't create updatedAt
    // eslint-disable-next-line no-dupe-keys
    updatedAt: 'updateTimestamp', // updatedAt should be called updateTimestamp
  },
  {
    hooks: {
      beforeCount(options) {
        options.raw = true;
      }
    }
  });

  // eslint-disable-next-line no-unused-vars
  swingTrades.associate = function (models) {
    // Define associations here
    // See http://docs.sequelizejs.com/en/latest/docs/associations/
    const {users} = models;

    swingTrades.belongsTo(users,{foreignKey: 'userId'});
    
  };

  return swingTrades;
};

我还没有找到任何解决方案。

【问题讨论】：

标签： node.js postgresql sequelize.js feathersjs

【解决方案1】：

那是因为模型名称和服务名称不匹配。这里有swingTrades

 **users.model.js**
 // eslint-disable-next-line no-unused-vars
 users.associate = function ({swingTrades) {
    users.hasMany(swingTrades, {
    as: 'swingTrades',
    foreignKey: 'userId' 
    }); 
 };

但是在swing-trades.model.js 中你有swing_trades

...
const swingTrades = sequelizeClient.define('swing_trades', {
    company: {
      type: DataTypes.STRING,
      allowNull: true
    }
  },
...

解决方案是在创建新服务时避免使用空格和 -。用一个词来命名一项服务。

【讨论】：