TypeORM:无法读取未定义的属性“”getParameters“”

Question

我正在使用express构建rest API，基于Wordpress数据库模式，您可以从here查看。

当我尝试inner join或left join时，每次都会得到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);

我还尝试了以下操作，但也出现了相同的错误：

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

我的实体：

帖子实体：

@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

我得到了代码工作，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，它的boooom工作！

但是我对代码做了很小的改动，以加入表的左侧

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);

我从github的一个问题中得到了它，不幸的是，在文档中没有提到。

Answer 2

我不熟悉这个库，但是看一下它的代码，它可能会在连接函数的this.setParameters(subQueryBuilder.getParameters());行抛出。为了解决这个问题，我会在Chrome Dev工具中启用stop on exception (源码标签页的小暂停图标在最右边)，然后看它抛出的时候，我认为这是因为你传递的WpPostMetaModel没有满足接口，它应该是一个返回正确数据的函数(在你的例子中，你传递的是JS中的类)：

以下是源代码中的代码：

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;
}

你可以试着在存储库(GitHub issue)上问一下，我想你只是用错了这个库。

很抱歉，这不是确切的答案，但有太多的文本可供评论。

Answer 3

在我的示例中，在创建connection对象时没有添加entities属性

我认为"Cannot read property 'getParameters‘of undefined“意味着它找不到特定表(Entity类)的元数据。

Please read the following Stack Overflow answer