使用关联的外键创建新的模型实例/记录

Question

我是续集的新手，遇到了一些语法问题。我制作了以下模型：

// User
sequelize.define('user', {
name: {
type: DataTypes.STRING,
allowNull: false,
},
});
// Type
sequelize.define('type', {
typeName: {
type: DataTypes.STRING,
allowNull: false,
},
});

我在它们之间创建了一个关联：

User.Type = User.belongsTo(Type, { foreignKey: { allowNull: false } })

并确认生成的 User 表具有对typeId的外键引用。

当我想创建一个新用户时，我还想传入一个"fan"或"band"字符串，该字符串将引用填充 Type 表的两种类型之一。如何在create函数中传达这一点？

const createUser = (req, res) => {
const { name, type } = req.body;
User.create({
name,
include: [{
association: User.Type
}]
})
.then(() => console.log('success'))
.catch((err) => console.log(err));
}

Answer 1

您可以创建用户并使用关联进行键入。以下示例使用"sequelize": "^5.21.3"

例如

index.js：

import { DataTypes } from 'sequelize';
import { sequelize } from '../../db';
export const User = sequelize.define('user', {
name: {
type: DataTypes.STRING,
allowNull: false,
},
});
export const Type = sequelize.define('type', {
typeName: {
type: DataTypes.STRING,
allowNull: false,
},
});
User.Type = User.belongsTo(Type, { foreignKey: { allowNull: false } });
export const createUser = (req, res) => {
const { name, type } = req.body;
return User.create(
{
name,
type: { typeName: type },
},
{ include: [{ association: User.Type }] },
)
.then(() => console.log('success'))
.catch((err) => console.log(err));
};

index.test.js：

import { createUser, Type, User } from './';
import { sequelize } from '../../db';
describe('59849396', () => {
beforeAll(async () => {
await sequelize.sync({ force: true });
});
afterAll(async () => {
await sequelize.close();
});
it('should create user with type correctly', async () => {
const mReq = { body: { name: 'Tom', type: 'band' } };
const mRes = {};
await createUser(mReq, mRes);
const type = await Type.findOne({ where: { typeName: 'band' } });
const user = await User.findOne({ where: { name: 'Tom' } });
expect(type.typeName).toBe(mReq.body.type);
expect(user.typeId).toBe(type.id);
});
});

测试结果：

PASS  src/examples/stackoverflow/59849396/index.test.js
59849396
✓ should create user with type correctly (74ms)
Test Suites: 1 passed, 1 total
Tests:       1 passed, 1 total
Snapshots:   0 total
Time:        2.253s, estimated 4s

运行测试后，检查数据库。

node-sequelize-examples=# select * from users;
id | name |         createdAt          |         updatedAt          | typeId 
----+------+----------------------------+----------------------------+--------
1 | Tom  | 2020-01-22 07:12:05.447+00 | 2020-01-22 07:12:05.447+00 |      1
(1 row)
node-sequelize-examples=# select * from types;
id | typeName |         createdAt         |         updatedAt         
----+----------+---------------------------+---------------------------
1 | band     | 2020-01-22 07:12:05.45+00 | 2020-01-22 07:12:05.45+00
(1 row)

如您所见，我们还在创建用户"Tom"时创建了"乐队"type。这意味着types表中也填充了数据行。