Foreign key property transformation processes undefined value upon save

[akwodkiewicz]

Issue Description

Expected Behavior

Newly created entity containing a foreign key id property (of a custom object type) is properly transformed and then inserted to the database.

Actual Behavior

Foreign key is ignored on some stage of the insert, resulting in an error during transformation of the property/foreign key value:

TypeError: Cannot read properties of undefined (reading 'value')
    at Object.to (/home/aw/project-3/typeorm-example/src/entities/post.entity.ts:31:19)
    at Function.transformTo (/home/aw/project-3/typeorm-example/src/util/ApplyValueTransformers.ts:28:28)
    at SqliteDriver.preparePersistentValue (/home/aw/project-3/typeorm-example/src/driver/sqlite-abstract/AbstractSqliteDriver.ts:319:44)
    at /home/aw/project-3/typeorm-example/src/query-builder/InsertQueryBuilder.ts:717:56
    at Array.forEach (<anonymous>)
    at /home/aw/project-3/typeorm-example/src/query-builder/InsertQueryBuilder.ts:688:25
    at Array.forEach (<anonymous>)
    at InsertQueryBuilder.createValuesExpression (/home/aw/project-3/typeorm-example/src/query-builder/InsertQueryBuilder.ts:687:23)
    at InsertQueryBuilder.createInsertExpression (/home/aw/project-3/typeorm-example/src/query-builder/InsertQueryBuilder.ts:406:39)
    at InsertQueryBuilder.getQuery (/home/aw/project-3/typeorm-example/src/query-builder/InsertQueryBuilder.ts:39:21)

Steps to Reproduce

I prepared a dedicated repository for this issue:

https://github.com/akwodkiewicz/typeorm-bug-report

README should explain how to use the repository to reproduce the error.

Nonetheless, below I'm pasting the trimmed version of the files used in this repository, so that this bug report does not need to rely on my repository in the future.

Id classes

/// src/entities/user-id.ts
export class UserId {
  constructor(public readonly value: string) {}
}

/// src/entities/post-id.ts
export class PostId {
  constructor(public readonly value: string) {}
}

Entities

/// src/entities/user.entity.ts
import { Column, Entity, PrimaryColumn } from "typeorm";
import { UserId } from "./user-id";

@Entity()
export class User {
  @PrimaryColumn({
    type: "text",
    transformer: {
      from(value: string) {
        return new UserId(value);
      },
      to(id: UserId) {
        return id.value;
      },
    },
  })
  id!: UserId;

  @Column()
  name!: string;
}

/// src/entities/post.entity.ts
import { Column, Entity, ManyToOne, PrimaryColumn } from "typeorm";
import { PostId } from "./post-id";
import { UserId } from "./user-id";
import { User } from "./user.entity";

@Entity()
export class Post {
  @PrimaryColumn({
    type: "text",
    transformer: {
      from(value: string) {
        return new PostId(value);
      },
      to(id: PostId) {
        return id.value;
      },
    },
  })
  id!: PostId;

  @ManyToOne(() => User)
  author?: User;

  @Column({
    type: "text",
    transformer: {
      from(value: string) {
        return new UserId(value);
      },
      to(id: UserId) {
        return id.value;
      },
    },
  })
  authorId!: UserId;
}

Faulty save

/// src/main.ts
import { dataSource } from "./data-source";
import { PostId } from "./entities/post-id";
import { Post } from "./entities/post.entity";
import { UserId } from "./entities/user-id";
import { User } from "./entities/user.entity";

const USER_ID = new UserId("abcd-1234");
const POST_ID = new PostId("first");

async function insertData() {
  const user = dataSource.manager.create(User, {
    id: USER_ID,
    name: "Tom",
  });
  await dataSource.manager.save(user);

  const post = dataSource.manager.create(Post, {
    authorId: USER_ID,
    id: POST_ID,
  });
  await dataSource.manager.save(post); // <-- this fails
}


async function main() {
  await dataSource.initialize();
  await insertData();
}

main().catch((e) => console.error(e));

My Environment

Dependency	Version
Operating System	WSL (Ubuntu on Windows 11)
Node.js version	18.12.0
Typescript version	4.9.3
TypeORM version	0.3.10

Additional Context

The error does not happen when the foreign keys and entity ids are typed as primitive strings.

I'm using sqlite driver, did not try to test it on other drivers.

Also, if you create the Post by specifying author: user instead of authorId: USER_ID then the insert is successful.

Relevant Database Driver(s)

DB Type	Reproducible
aurora-mysql	no
aurora-postgres	no
better-sqlite3	no
cockroachdb	no
cordova	no
expo	no
mongodb	no
mysql	no
nativescript	no
oracle	no
postgres	no
react-native	no
sap	no
spanner	no
sqlite	yes
sqlite-abstract	no
sqljs	no
sqlserver	no

Are you willing to resolve this issue by submitting a Pull Request?

• ✖️ Yes, I have the time, and I know how to start.
• ✅ Yes, I have the time, but I don't know how to start. I would need guidance.
• ✖️ No, I don’t have the time, but I can support (using donations) development.
• ✖️ No, I don’t have the time and I’m okay to wait for the community / maintainers to resolve this issue.

[akwodkiewicz]

I started debugging this. The most interesting things during the save operation happen inside ColumnMetadata when this is the authorId column.

---

This line:

typeorm/src/metadata/ColumnMetadata.ts

Lines 785 to 786 in dbc1b2e

	const relatedEntity =
	this.relationMetadata.getEntityValue(entity)

is called when:

• this is the ColumnMetadata representing authorId property / author_id database column

• entity is a plain object representing a Post entity: {"authorId":{"value":"abcd-1234"},"id":{"value":"first"}}

• this.relationMetadata contains the following properties:

  • propertyName: 'author'

  • propertyPath: 'author'

  • joinColumns[0].databaseName: 'author_id'

---

When you step into RelationMetadata.getEntityValue, this is what is eventually returned from the function:

typeorm/src/metadata/RelationMetadata.ts

Line 479 in dbc1b2e

return entity[this.propertyName]

where:

• entity is still the same {"authorId":{"value":"abcd-1234"},"id":{"value":"first"}} as before

• but this.propertyName is 'author'

So the expression entity[this.propertyName] returns undefined.

---

So back to ColumnMetadata. Because of various conditional checks the value is then set in

typeorm/src/metadata/ColumnMetadata.ts

Lines 805 to 807 in dbc1b2e

	value = this.referencedColumn.getEntityValue(
	entity[this.propertyName],
	)

where:

• this.referencedColumn is the id column of the User entity
• ⚠️ ⚠️ ⚠️ entity[this.propertyName] is {"value":"abcd-1234"} -- this is what is passed as entity!!! ⚠️ ⚠️ ⚠️

Obviously {"value":"abcd-1234"} is not a correct User entity, if anything it should be { "id": {"value":"abcd-1234"}}.

Then this line is called

typeorm/src/metadata/ColumnMetadata.ts

Line 816 in dbc1b2e

value = entity[this.propertyName]

and this value is returned several lines later.

But because this.propertyName is "id" and entity is {"value":"abcd-1234"}, the returned value is undefined. ⚠️

---

I don't know whether this itself is a bug or is it only a part of the whole insert operation that is supposed to work like this, but I have a feeling that this might be the root cause

[akwodkiewicz]

I believe that checking if the column is an object literal is the culprit for this bug. If it wasn't for the true value of

ObjectUtils.isObject(relatedEntity)

in line {797} of ColumnMetadata, the UserId object would not be treated as an entity that requires to be traversed for the value, but actually as the final value (and I believe this is the case when the column properties are typed as strings).

I am not sure if the transformation step is going to kick in later or does it also requires some more changes.