Retrieving ID in @AfterInsert operation

[alex5207]

Issue type:

[X ] question
[ ] bug report
[ ] feature request
[ ] documentation issue

Database system/driver:

[ ] cordova
[ ] mongodb
[ ] mssql
[X ] mysql / mariadb
[ ] oracle
[ ] postgres
[ ] sqlite
[ ] sqljs
[ ] react-native
[ ] expo

TypeORM version:

[X] latest
[ ] @next
[ ] 0.x.x (or put your version here)

Steps to reproduce or a small repository showing the problem:

I have two entities, Person and Photo which has a one-to-one relationship. After creating a person I'm trying to create a Photo in the @AfterInsert part. However, when trying to fetch the id of the newly created person, it returns undefined (

export class Person {

  @AfterInsert()

  public async handleAfterInsert() {
    const person = await getConnection()
      .getRepository(Person)                     //<--- This is where the problem is
      .findOne(this.id);

    //Insert into Photo
      const photo = New Photo();
      photo.person = person;

    await getConnection()
      .getRepository(Photo)
      .save(photo);
  }

  @PrimaryGeneratedColumn()
  public id: number;

  @OneToOne(type => Photo, photo => photo.person)
  public photo: Photo
}
`

[vlapo]

Did you use save() or insert() method? Because insert() method is just simple INSERT in DB and save method do lot of magic around - like fill primary generated column.

[alex5207]

@vlapo When creating a Person I am using the save() method.
Note: I can verify that the ID is present if I do a console.log(this.id).

So, its like the repository is not updated quickly enough

[vlapo]

Understand now. I thought this.id is undefined before. This is problem of transactions. Insert statement is done but transaction is not committed yet so person is not available in new select.

But I do not understand why you need select person again? You have your entity in this so use it.

@AfterInsert()
public async handleAfterInsert() {
    //Insert into Photo
    const photo = New Photo();
    photo.person = this;

    await getConnection()
      .getRepository(Photo)
      .save(photo);
}

[alex5207]

@vlapo I see what you mean. When I just set photo.person = this i get an ER_LOCK_WAIT_TIMEOUT: Lock wait timeout exceeded; try restarting transaction +54168ms

Not sure why that's not working...

[vlapo]

Yeah you need use same entityManager instance because of transactions. In short you have to use subscriber instead of listener.

@EventSubscriber()
export class PersonSubscriber implements EntitySubscriberInterface<Person> {

    listenTo() {
        return Person;
    }

    async afterInsert(event: InsertEvent<Person>) {
        const photo = new Photo();
        photo.person = event.entity;

        await event.manager
            .getRepository(Photo)
            .save(photo);
    }
}

More info: #743 and #1705 (comment)

[alex5207]

@vlapo - Thanks a lot for your example. Forgive me, but I somehow still cannot get this to work.
I have implemented exactly as in your example in a seperate file from the Person entity.

Nothing really happens when I insert a new Person. I tried doing a console.log('inserted person') inside afterInsert to try and verify whether anything was happening. Nothing came from it.

I tried to read [https://github.com/typeorm/typeorm/blob/master/docs/listeners-and-subscribers.md#what-is-a-subscriber] as well. Seems to provide almost an identical example to yours.

Do I need to create an instance of this class anywhere, or?

Thanks for your patience
BR

[vlapo]

You have to define subscribers in your connection options. Check this http://typeorm.io/#/connection-options, option subscribers.

I am really suprised we do not have any note about this option in https://github.com/typeorm/typeorm/blob/master/docs/listeners-and-subscribers.md.

[alex5207]

Worked like a charm - Thanks a lot @vlapo