TypeORM：无法读取未定义的属性“getParameters”

Question

我正在使用 Express 和 typeORM 为基于 Wordpress 数据库模式的 Mysql 构建 rest API，您可以从 here 进行检查。

当我尝试inner join 或left join 时，我每次都会收到Cannot read property 'getParameters' of undefined 错误。

我的代码：

const posts = await this.postRepository
    .createQueryBuilder('posts')
    .innerJoinAndSelect(WpPostMetaModel, 'postmeta', 'posts.id = postmeta.post')
    .getMany()

response.send(posts);

我也尝试了以下相同的错误：

let posts = await createQueryBuilder('WpPostsModel')
    .leftJoinAndSelect(WpPostMetaModel, 'postmeta', 'postmeta.post_id = WpPostsModel.ID')
    .getManyAndCount()

我的实体：

发布实体：

@Entity({ name: 'wp_posts', synchronize: false })
export class WpPostsModel {

    @PrimaryGeneratedColumn({ name: 'ID' })
    public id?: number;

    @Column({ name: 'post_date' })
    public date?: Date;

    @Column({ name: 'post_date_gmt' })
    public date_gmt?: Date;

    ...etc

    @ManyToMany(() => WpTermTaxonomyModel)
    @JoinTable({
        name: 'wp_term_relationships',
        joinColumn: {
            name: 'object_id',
            referencedColumnName: 'ID'
        },
        inverseJoinColumn: {
            name: 'term_taxonomy_id',
            referencedColumnName: 'termTaxonomyId'
        }
    })
    public categories?: WpTermTaxonomyModel[];

}

发布元实体：

@Entity({ name: 'wp_postmeta' })
export class WpPostMetaModel {

    @PrimaryGeneratedColumn({ name: 'meta_id' })
    public metaId?: number;

    @OneToOne(() => WpPostsModel, {eager: true, cascade: true})
    @JoinColumn({ name: 'post_id' })
    public post?: WpPostsModel

    @Column({ name: 'meta_key' })
    public metaKey?: string;

    @Column({ name: 'meta_value' })
    public metaValue?: string;

}

更新：整个错误

(node:1043) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'getParameters' of undefined
    at SelectQueryBuilder.join (/Volumes/Partion-2/Projects/republic-news/src/query-builder/SelectQueryBuilder.ts:1319:52)
    at SelectQueryBuilder.leftJoin (/Volumes/Partion-2/Projects/republic-news/src/query-builder/SelectQueryBuilder.ts:284:14)
    at SelectQueryBuilder.leftJoinAndSelect (/Volumes/Partion-2/Projects/republic-news/src/query-builder/SelectQueryBuilder.ts:364:14)
    at WpPostsController.<anonymous> (/Volumes/Partion-2/Projects/republic-news/src/controllers/post.controller.ts:54:14)
    at step (/Volumes/Partion-2/Projects/republic-news/src/controllers/post.controller.ts:33:23)
    at Object.next (/Volumes/Partion-2/Projects/republic-news/src/controllers/post.controller.ts:14:53)
    at /Volumes/Partion-2/Projects/republic-news/src/controllers/post.controller.ts:8:71
    at new Promise (<anonymous>)
    at __awaiter (/Volumes/Partion-2/Projects/republic-news/src/controllers/post.controller.ts:4:12)
    at WpPostsController.getAllPosts (/Volumes/Partion-2/Projects/republic-news/src/controllers/post.controller.ts:31:86)
(node:1043) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:1043) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Answer 1

我不熟悉该库，但查看它的代码，它可能会在 join 函数中的 this.setParameters(subQueryBuilder.getParameters()); 行抛出。要解决此问题，我将在 Chrome 开发工具中启用异常停止（最右侧的源选项卡小暂停图标）并查看它抛出时，我认为这是因为 WpPostMetaModel 你传递的不符合接口它应该是一个函数（在您的情况下，您传递类 - 在 JS 中是相同的）返回正确的数据：

这是源代码中的代码：

let subQuery: string = "";
if (entityOrProperty instanceof Function) {
    const subQueryBuilder: SelectQueryBuilder<any> = (entityOrProperty as any)(((this as any) as SelectQueryBuilder<any>).subQuery());
    this.setParameters(subQueryBuilder.getParameters()); // I think this line throw error
    subQuery = subQueryBuilder.getQuery();

} else {
    subQuery = entityOrProperty;
}

您可以尝试在 repo (GitHub issue) 上询问，我认为您只是使用库错误。

抱歉，这不是完全正确的答案，但要评论的文字太多。

Answer 2

我得到了代码，但我真的不知道为什么？！！ :"D

刚刚删除了我的帖子元实体并重新创建了它，它正在工作！

但我对左加入表格的代码做了一点小改动

const posts = await this.postRepository.createQueryBuilder('post')
    .leftJoinAndMapOne('post.meta', WpPostmetaModel, 'postmeta', 'postmeta.post  = post.id') 
    // leftJoinAndMapOne instead of letftJoinAndSelect as leftJoinAndSelect didn't return the joined table
    .getMany();

response.send(posts);

不幸的是，我是从 github 的一个问题中得到的，但没有在文档中提及。

Answer 3

在我的例子中，我在创建连接对象时没有添加实体属性

我认为“无法读取未定义的属性'getParameters'”意味着它无法找到特定表（实体类）的元数据。

Please read the following Stack Overflow answer