[query] select `e0`.`id`, `e0`.`author_id`, `a1`.`id` as `a1__id` from `book` as `e0` left join `author` as `a1` on `e0`.`author_id` = `a1`.`id` where `e0`.`id` = X'671b206cf43b45dbaf5c32c7eb5269bc' [took 2 ms]
JIT runtime error: Stringified UUID is invalid

function(entity, data, factory, newEntity, convertCustomTypes) {
  if (typeof data.id !== 'undefined') {
    if (convertCustomTypes) {
      const value = convertToJSValue_id(data.id);
      data.id = convertToDatabaseValue_id(value);
      entity.id = value;
    } else {
      entity.id = data.id;
    }
  }
  if (data.author === null) {
    entity.author = null;
  } else if (typeof data.author !== 'undefined') {
    if (isPrimaryKey(data.author, true)) {
      entity.author = factory.createReference('Author', data.author, { merge: true });
    } else if (data.author && typeof data.author === 'object') {
      entity.author = factory.create('Author', data.author, { initialized: true, merge: true, newEntity });
    }
  }
  if (data.author != null && convertCustomTypes) {
    const value = convertToJSValue_author(data.author);
    data.author = convertToDatabaseValue_author(value);
  }
}
[Nest] 862668   - 12/24/2020, 4:15:15 PM   [ExceptionsHandler] Stringified UUID is invalid +198036ms
TypeError: Stringified UUID is invalid
    at Object.stringify (/home/virchenko/Projects/test/test-project/node_modules/uuid/dist/stringify.js:32:11)
    at UuidBinaryType.convertToJSValue (/home/virchenko/Projects/test/test-project/dist/src/uuid-binary-type.js:11:23)
    at /home/virchenko/Projects/test/test-project/node_modules/@mikro-orm/core/hydration/ObjectHydrator.js:109:91
    at eval (eval at createFunction (/home/virchenko/Projects/test/test-project/node_modules/@mikro-orm/core/utils/Utils.js:580:52), <anonymous>:21:19)
    at Function.callCompiledFunction (/home/virchenko/Projects/test/test-project/node_modules/@mikro-orm/core/utils/Utils.js:591:20)
    at ObjectHydrator.hydrate (/home/virchenko/Projects/test/test-project/node_modules/@mikro-orm/core/hydration/ObjectHydrator.js:23:23)
    at EntityFactory.hydrate (/home/virchenko/Projects/test/test-project/node_modules/@mikro-orm/core/entity/EntityFactory.js:81:27)
    at EntityFactory.create (/home/virchenko/Projects/test/test-project/node_modules/@mikro-orm/core/entity/EntityFactory.js:35:14)
    at SqlEntityManager.findOne (/home/virchenko/Projects/test/test-project/node_modules/@mikro-orm/core/EntityManager.js:197:42)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)

import { Entity, ManyToOne, PrimaryKey} from '@mikro-orm/core';
import { Author } from './author';
import { v4 } from 'uuid';
import { UuidBinaryType } from '../uuid-binary-type';

@Entity({
  tableName: 'book',
})
export class Book {
  @PrimaryKey({ type: UuidBinaryType })
  readonly id = v4();

  @ManyToOne()
  author!: Author;
}

import { Entity, PrimaryKey } from '@mikro-orm/core';
import { v4 } from 'uuid';
import { UuidBinaryType } from '../uuid-binary-type';

@Entity({
  tableName: 'author',
})
export class Author {
  @PrimaryKey({ type: UuidBinaryType })
  readonly id = v4();
}

import { Type } from '@mikro-orm/core';
import { parse, stringify } from 'uuid';

export class UuidBinaryType extends Type<string, Buffer> {
  convertToDatabaseValue(value: string): Buffer {
    return Buffer.from(parse(value));
  }

  convertToJSValue(value: Buffer): string {
    return stringify(value);
  }

  getColumnType(): string {
    return 'binary(16)';
  }
}

{
 ...
  loadStrategy: LoadStrategy.JOINED,
}

const author = new Author();
const book = new Book();
book.author = author;

this.em.persist(author);
this.em.persist(book);

await this.em.flush();

await this.em.getRepository(Book).findOne(id, ['author']);

import { Type } from '@mikro-orm/core';
import { parse, stringify } from 'uuid';

export class UuidBinaryType extends Type<string, Buffer> {
  convertToDatabaseValue(value: string): Buffer {
    return Buffer.from(parse(value));
  }

  convertToJSValue(value: any): string {
    if (value.hasOwnProperty('id')) {
      return Buffer.isBuffer(value.id) ? stringify(value.id) : value.id;
    }

    return stringify(value);
  }

  getColumnType(): string {
    return 'binary(16)';
  }
}

Author { id: <Buffer 96 dc 32 86 75 40 42 a4 91 1c 09 5f 32 35 fe b3> }