本文以RBAC权限管理中的用户和角色举例，两个实体存在多对多的关系，一个用户拥有多个角色，一个角色属于多个用户。typeorm的中文文档没有对自定义中间表的说明，发现英文有相关说明，但示例代码貌似有问题。

一、中间表有自定义字段的处理

在用户user和role实体之外，新建一个roleUse的实体(记录用户和角色的关联关系)，如此本来是多对多的关系，变成了user和role与roleUser二组一对多的关系，这样虽然会多定义一个实体，但好处是可以中间表可以扩展定义其它额外的数据

用户实体 user.entity.ts

import { Entity, Column, Index, ManyToMany, JoinColumn, OneToMany, JoinTable, PrimaryGeneratedColumn, CreateDateColumn, UpdateDateColumn } from 'typeorm';

import { Role } from '../../admin/role/role.entity';

import { UserRole } from '../../admin/role/roleUser.entity';

@Entity()

export class User {

@PrimaryGeneratedColumn()

id: number;

@Column({ length: 100 })

@Index({ unique: true })

name: string;

@OneToMany(type => UserRole, userRole => userRole.user)

userRoles: UserRole[];

}

角色实体role.entity.ts

import { Entity, Column, ManyToMany, OneToMany, JoinTable, JoinColumn } from 'typeorm';

import { BaseEntity } from'../../../common/base/base.entity';

import { UserRole } from './roleUser.entity';

@Entity('role')

export class Role extends BaseEntity {

@Column({ length:100})

role_name: string;

@OneToMany(type=> UserRole, userRole =>userRole.role)

userRoles: UserRole[];

}

中间表实体 roleUser.entity.ts (主健)

import { Entity, PrimaryGeneratedColumn, JoinColumn, Column, CreateDateColumn, UpdateDateColumn, ManyToOne } from 'typeorm';

import { BaseEntity } from '../../../common/base/base.entity';

import { User } from '../../web/user/user.entity';

import { Role } from './role.entity';

@Entity()

export class UserRole {

@PrimaryGeneratedColumn()

public id: number;

@CreateDateColumn()

created_time: Date;

@UpdateDateColumn()

updated_time: Date;

@ManyToOne(type => User, user => user.userRoles)

@JoinColumn({name: 'user_id'})

user: User;

@ManyToOne(type => Role, role => role.userRoles)

@JoinColumn({name: 'role_id'})

role: Role;

}

中间表定义roleUser.entity.ts(复合主键)

import { Entity, PrimaryGeneratedColumn, JoinColumn, Column, CreateDateColumn, UpdateDateColumn, ManyToOne } from 'typeorm';

import { BaseEntity } from '../../../common/base/base.entity';

import { User } from '../../web/user/user.entity';

import { Role } from './role.entity';

@Entity()

export class UserRole {

@CreateDateColumn()

created_time: Date;

@UpdateDateColumn()

updated_time: Date;

@ManyToOne(type => User, user => user.userRoles, { primary: true })

@JoinColumn({name: 'user_id'})

user: User;

@ManyToOne(type => Role, role => role.userRoles, { primary: true })

@JoinColumn({name: 'role_id'})

role: Role;

}

二、无中间表的多对多实体定义，又分为单向和双向，单向是仅在一侧与关系装饰器的关系， 双向是与关系两侧的装饰者的关系。具体官网文档：https://typeorm.io/#/relations，此处主要讲双向

角色实体

import { Entity, Column, ManyToMany, OneToMany, JoinTable, JoinColumn } from 'typeorm';

import { BaseEntity } from '../../../common/base/base.entity';

import { User } from '../../web/user/user.entity';

@Entity('role')

export class Role extends BaseEntity {

@Column({ length: 100 })

role_name: string;

@Column({ length: 100 })

remark: string;

// 无中间实体表的配置

@ManyToMany(type => User, user => user.roles, { cascade: true })

users: User[];

}

用户实体

import { Entity, Column, Index, ManyToMany, JoinColumn, OneToMany, JoinTable, PrimaryGeneratedColumn, CreateDateColumn, UpdateDateColumn } from 'typeorm';

import { Role } from '../../admin/role/role.entity';

@Entity()

export class User {

@PrimaryGeneratedColumn()

id: number;

@Column({ length: 100 })

@Index({ unique: true })

name: string;

// 无中间实体表的配置

@ManyToMany(type => Role, role => role.users)

@JoinTable({

name: 'user_role',

joinColumns: [

{name: 'user_id'}

],

inverseJoinColumns: [

{name: 'role_id'}

]

})

// 下面的定义也能实现

// @JoinTable({

// name: 'user_role',

// joinColumn: { name: 'user_id' },

// inverseJoinColumn: { name: 'role_id' },

// })

roles: Role[];

}