Using serializr with TypeORM

[krishnabrq]

I am working on a Express.js backend and using TypeORM for DB operations. As in TypeORM we Entity classes for DB tables, I used the same classes for (de)serialization purpose too. I am using serializr for this. For example:

import { Column, Entity, ManyToOne, OneToMany, PrimaryGeneratedColumn } from "typeorm";

// The User class is a TypeORM entity as well as be used for (de)serialization
@Entity({ name: "users" })
class User {
  @serializable
  @PrimaryGeneratedColumn()
  id: number;

  @serializable
  @Column({ nullable: false })
  name: string;
}

But the issue occurs when I have something like following:

@Entity({ name: "posts" })
class Post {
  @serializable
  @PrimaryGeneratedColumn()
  id: number;

  @serializable
  @Column({ nullable: false })
  desc: string;

  @serializable(list(object(Comment)))
  @OneToMany(() => Comment, (c) => c.post, {
    nullable: true,
  })
  comments: Comment[];
}

@Entity({ name: "comments" })
class Comment {
  @serializable
  @PrimaryGeneratedColumn()
  id: number;

  @serializable
  @Column({ nullable: false })
  desc: string;

  @serializable(object(Post))
  @ManyToOne(() => Post, (p) => p.comments, {
    nullable: false,
  })
  post: Post;
}

This creates a circular dependency and getting the following error from serializr:

Error: [serializr] No modelSchema provided. If you are importing it from another file be aware of circular dependencies.

---

I found about identifier() and reference() in serializr documentation and tried is as following:

@Entity({ name: "posts" })
class Post {
  @serializable
  @PrimaryGeneratedColumn()
  id: number;

  @serializable
  @Column({ nullable: false })
  desc: string;

  @serializable(list(reference(Comment)))
  @OneToMany(() => Comment, (c) => c.post, {
    nullable: true,
  })
  comments: Comment[];
}

@Entity({ name: "comments" })
class Comment {
  @serializable(identifier())
  @PrimaryGeneratedColumn()
  id: number;

  @serializable
  @Column({ nullable: false })
  desc: string;

  @ManyToOne(() => Post, (p) => p.comments, {
    nullable: false,
  })
  post: Post;
}

But still getting the same error. Please suggest me any fix for this.