捕获并返回返回错误时，Rxjs 可观察抛出错误

Question

Hi I am getting this error "you provided an invalid object where a stream was expected. You can provide an Observable, Promise, Array, or Iterable" when this http request is called from my effects.

deleteAccount(accountId: string): Observable<any> {
    return this.http.delete(FUNDING_ACCOUNT_DELETE_URL
      .replace(ACCOUNT_ID, accountId)).pipe(
        timeout(2000),
        catchError(err => { 
          return err; })
      );
  }

@Effect()
  paymentOptionRemove = this.actions
    .ofType(ActionTypes.PAYMENT_OPTION_REMOVE).pipe(
      switchMap((action: PaymentOptionRemoveAction) =>
        this.service.deleteAccount(action.payload).pipe(
          map(
            _ => new PaymentOptionRemovedAction()),
          // tslint:disable-next-line:arrow-return-shorthand
          catchError(err => {
            if (err) {
              console.log(err);
            }
            return of(new PaymentOptionRemoveErrorAction());
          })
        ))
    );

Answer 1

From the deleteAccount function, you are supposed to return an Observable . In the catchError block, you are trying to return the err , which is not observable.

Use throwError from rxjs :

throwError is a function from rxjs that creates an Observable that emits only error to the subscriber. Designed for use case such as you have.

import { throwError } from 'rxjs';

Inside the delete function, use like:

return throwError(err);