How to pass action data downstream a pipeable operator stream in rxjs?

Question

I have a situation where I want to access action payload in a third level operation. I was able to such thing in lettable operators but how can I do the same with pipeable operator?

this my code,

 @Effect()
  onTrySignin = this.actions$.pipe(
    ofType(AuthActions.TRY_SIGNIN),
    map((action: AuthActions.TrySignin) => {
      return action.payload;
    }),
    switchMap(action => {
      return this.httpService
        .postRequest('UserAccounts/Login', action.credentials);
    }), catchError((error: HttpErrorResponse) => {
      return Observable.of(new AuthActions.FailedAuth(error));
    }),
    mergeMap((response: any) => {
      // how to access action payload here?
    })
  );

Answer 1

You can use map() to pass data along an observable chain like this:

// both foo and bar will be available on next()
from(AsyncFooData()).pipe(
  concatMap(foo => AsyncBarData().pipe(
    map(bar => ({foo, bar})
  )),
  tap(val => console.log(val), // chain more operators here...
).subscribe(({foo, bar}) => {
  // do stuff with foo and bar
})

FWIW, I took this answer from this question where I posted a somewhat similar answer.