ngrx showing "Typerror: entities.reduce is not a function" error even when `entities` contains data

Question

I'm trying to use ngrx entity dataservice for the first time

• https://ngrx.io/guide/data
• https://ngrx.io/guide/data/entity-dataservice

The API call is being made and I'm recieving the expected data

But when ngrx tries to proccess it it gets an error on the reduce method

I have checked other similar questions:

• Map and Reduce JSON Objects with JavaScript
• "TypeError: x is not a function" even when code works

But have not found what is causing this.

The response contains an id and is not undefined, how can I solve this ?

Since the error is happening inside ngrx I'm not sure about what part of my code show you to help me address this.

Answer 1

This happens when te result contains an array of objects and another data, so the data has to be mapped - http://github.com/ngrx/platform/issues/2434#issuecomment-751560440

Answer 2

Make sure you map your response as Array. This will resolve your issue:

Example :

@Injectable()
export class ForReportsDataService extends DefaultDataService<any> {


    constructor(http:HttpClient, httpUrlGenerator: HttpUrlGenerator, private dataService: DataService) {
        super('forReport', http, httpUrlGenerator);
    }

    getAll(): Observable<any> {
        return from(this.dataService.GET("/api/reports").pipe(     // map here
            map(res => res["items"])                               // map here
        ));
    }

}