many to many? about ngrx-entity-relationship HOT 7 CLOSED

Resolved

from ngrx-entity-relationship.

Hi again,

might you explain how you tried to search for it? I'll try to add suitable keywords to improve search appearance.

There are several options:

1. company should provide staffId.

export interface Company {
    id: string;
    name: string;

    staffId?: Array<string>; // and array of ids to select
    staff?: Array<User>;

    admin?: User;
    adminId?: string;

    address?: Address;
    addressId?: string;
}

const companyWithEmployees = rootEntity(
    companySelector,
    relatedEntity( // relatedEntity supports single ids and arrays of them.
        userSelector,
        'staffId',
        'staff',
    ),
);

export interface User {
    companyId?: string;
}

const companyWithEmployees = rootEntity(
    companySelector,
    childEntity( // childEntity searches for suitable users based on companyId == company.id.
        userSelector,
        'companyId',
        'staff',
    ),
);

I found you looking for the words "ngrx entity one to many":
https://stackoverflow.com/questions/61933118/ngrx-how-to-many-to-many-relationship-between-entities

I've been looking for weeks:
normalizing
https://redux.js.org/recipes/structuring-reducers/normalizing-state-shape
https://github.com/paularmstrong/normalizr

ngrx orm
https://gist.github.com/musou1500/6f7649bf230f1c7e06280b0103519b8b

from ngrx-entity-relationship.

Aha, thanks.

I'll try to promote "ngrx orm" and "ngrx normalizing". For the last weeks I've been working on redux version, because of that, I think, the next update will be ready only in 2-3 weeks.

Btw, does the thing about many-to-many work for you?

from ngrx-entity-relationship.

hi,

Hi, I tried the implementation, but I have an error.

companyId successfully finds it in the User entity
https://github.com/jucasoft/ngrx-entity-crud-prime-ng-boilerplate/blob/a8e3103ef42d063c832d04e190de45c9dc629f79/src/app/main/models/vo/user.ts#L8

staff, does not find it in Compani (even if present) it seems to look for it in User.
https://github.com/jucasoft/ngrx-entity-crud-prime-ng-boilerplate/blob/a8e3103ef42d063c832d04e190de45c9dc629f79/src/app/root-store/company-store/selectors.ts#L29

from ngrx-entity-relationship.

Yeah, my bad. Because it's an array not childEntity, but childrenEntity should be used.

const companyWithEmployees = rootEntity(
  selectState,
  childrenEntities(
    UserStoreSelectors.selectState,
    'companyId',
    'staff',
  ),
);

another thing is that with the current approach it causes Warning: Circular dependency detected:.
It's quite common because of cross relationships.

it's caused by

export const selectState: MemoizedSelector<object, State> = createFeatureSelector<State>(Names.NAME);

and

export const selectState: MemoizedSelector<object, State> = createFeatureSelector<State>(Names.NAME);

it should be in any other file, but not within ngrx-entity-relationship selectors.
I put them in the state.ts usually.

then it's like that: https://take.ms/nLoxh

I've created a PR: jucasoft/ngrx-entity-crud-prime-ng-boilerplate#1

from ngrx-entity-relationship.