Loopback 4删除关系

import {belongsTo, Entity, model, property} from '@loopback/repository';
import {Post} from './post.model';

@model({settings: {strict: false}})
export class User extends Entity {
  @property({
    type: 'number',
    id: true,
    generated: true,
  })
  id?: number;

  @property({
    type: 'string',
    required: true,
  })
  name: string;

  @belongsTo(() => Post, {keyTo: 'userId'})
  posts?: Post[];
}

const user = await this.userRepository.findById(userId);
if (user) {
  user.posts = [];
  await this.userRepository.update(user);
}

await this.userRepository.posts(userId).delete();

// user.model.ts
import {belongsTo, Entity, model, property} from '@loopback/repository';
import {Post} from './post.model';

@model({settings: {strict: false}})
export class User extends Entity {
  @property({
    type: 'number',
    id: true,
    generated: true,
  })
  id?: number;

  @property({
    type: 'string',
    required: true,
  })
  name: string;

  @belongsTo(() => Post, {keyTo: 'userId'})
  posts?: Post[];
}

// post.model.ts
import {Entity, model, property, hasMany} from '@loopback/repository';
import {User} from './user.model';

@model({settings: {strict: false}})
export class Post extends Entity {
  @property({
    type: 'number',
    id: true,
    generated: true,
  })
  id?: number;

  @property({
    type: 'string',
    required: true,
  })
  title: string;

  @hasMany(() => User, {keyTo: 'userId'})
  users?: User[];
}

// user.repository.ts
import {DefaultCrudRepository} from '@loopback/repository';
import {User} from '../models';
import {inject} from '@loopback/core';

export class UserRepository extends DefaultCrudRepository<
  User,
  typeof User.prototype.id
> {
  constructor(@inject('datasources.db') dataSource: juggler.DataSource) {
    super(User, dataSource);
  }
}

// post.repository.ts
import {DefaultCrudRepository} from '@loopback/repository';
import {Post} from '../models';
import {inject} from '@loopback/core';

export class PostRepository extends DefaultCrudRepository<
  Post,
  typeof Post.prototype.id
> {
  constructor(@inject('datasources.db') dataSource: juggler.DataSource) {
    super(Post, dataSource);
  }
}