How to add relations buried in an embedded entity?

[pedramardakani]

Hi there. I have been trying to make this work, but no luck so far.

I want to create an invoice, which might assign an inspector who would approve the quantity of things inside this invoice. The structure below should reflect that:

The Invoice entity, contains an embedded quantity entity of type Inspection, which holds a Many-to-One relation with the User entity.

A minimal preview would be like the following:

@Entity()
export class User {
  @PrimaryGeneratedColumn('uuid')
  uuid: string

  @Column()
  name: string

  // other fields
}

export abstract class Inspection {
  @ManyToOne(() => User)
  inspector?: User;

  // other fields 
}

@Entity()
export class Invoice {
  @PrimaryGeneratedColumn('uuid')
  uuid: string

  @Column(() => Inspection)
  quantity?: Inspection

  // other fields
}

Now, let's say I want to get the invoice, and load the inspector information inside (e.g. name) as well. It is possible to use TypeORM relations like so:

const id = "some-valid-uuid-here"
async findOne(id: string) {
  return this.invoiceRepository.findOne({ where: { uuid: id }, relations: ['quantity.inspector'] })
}

But I can't get it to work with same relation specification inside paginate config. For instance:

static PAGINATION_CONFIG: PaginateConfig<Invoice> = {
  // other settings with filter, sortable columns, etc.

  relations: ['quantity.inspector'],
  // P.S the form below doesn't work as well
  // relations: { quantity: { inspector: true } }

It raises the error:

[Nest] 912690 - 12/12/2023, 3:25:40 PM ERROR [ExceptionsHandler] Relation with property path quantity in entity was not found.
TypeORMError: Relation with property path quantity in entity was not found.
at JoinAttribute.getValue (/path/to/project/src/query-builder/JoinAttribute.ts:187:23)
at JoinAttribute.get relation [as relation] (/path/to/project/src/query-builder/JoinAttribute.ts:191:53)
at JoinAttribute.get metadata [as metadata] (/path/to/project/src/query-builder/JoinAttribute.ts:203:18)
at SelectQueryBuilder.join (/path/to/project/src/query-builder/SelectQueryBuilder.ts:2038:53)
at SelectQueryBuilder.leftJoin (/path/to/project/src/query-builder/SelectQueryBuilder.ts:467:14)
at SelectQueryBuilder.leftJoinAndSelect (/path/to/project/src/query-builder/SelectQueryBuilder.ts:607:14)
at /path/to/project/node_modules/nestjs-paginate/src/paginate.ts:226:30
at Array.forEach ()
at createQueryBuilderRelations (/path/to/project/node_modules/nestjs-paginate/src/paginate.ts:222:36)
at paginate (/path/to/project/node_modules/nestjs-paginate/src/paginate.ts:236:9)

P.S:

I have read usage-with-relations, I know about the merged pull request Embedded entities #369, I have the latest nestjs-paginate installed, i.e 8.6.0.

[ppetzold]

umm.. embedded entities don't need any relation definition - see https://github.com/ppetzold/nestjs-paginate/blob/master/src/paginate.spec.ts#L1235

both notations relations: ['quantity.inspector'] and relations: { quantity: { inspector: true } } perform actual table joins, that's why you getting the error above.

Your case where an embedded entity holds another relation is simply an edge case where this lib has no coverage yet - and hence the implementation didn't consider this.

You are welcome to submit a bug fix :)

[pedramardakani]

Woah thank you for the quick answer! Sure, I'll try doing that 👍