equivalent of effect using observable param, with signals

[Massimiliano-Perelli]

With ComponentStore, I'm using a really powerful feature of effects which can react on a input param stream. For example if I got this effect:

getMovies = this.effect((partitionId$: Observable<string>)

and the consumer does

myStore.getMovies(partitionId$) where partitionId$ it's an observable,

then the getMovies code will be executed for free, each time partitionId$ emits a new value.

Since now my app is getting full of signals over observables I was asking myself if the it would be possible to have a similar functionality passing signals instead of observable.
Maybe it is already possible within signal store?

As a workaround I can also make use of toObservable, but I wonder if there is a cleaner way.

[jits]

@Massimiliano-Perelli — check out https://ngrx.io/guide/signals/signal-method (an excellent recent addition by Rainer H).

[Massimiliano-Perelli]

``Hi @jits thanks for your reply, I wasn't aware of signal-method. I have checked it but probably it does not fit for me because I need to do some async call and do a tapResponse inside its body as I usually do inside an effect. If I want to do so I think I should subscribe manually to the async method or so.

BTW I want to point out an aspect of signal-method, because I've tried it in another use case. Basically I'm in a modal and I want the modal closes once the signal exposed by the store which is doing the operations emits:

  readonly closeDialogOnSucceed = signalMethod<OperationResultBase | undefined>(result => {
    if (validUpdate(result)) {
      this.modalRef()?.hide();
    }
  });

  constructor() {
    this.closeDialogOnSucceed(this.nodeMover.moveSucceed); // where moveSucceed is a signal
  }

export const validUpdate = (update: OperationResultBase | undefined) =>
  (update && (Date.now() - update.timeStamp <= 300)) ? update : undefined;

With this code this mechanism it is not working since when the signal value is validated it is bigger than 300 ms, around 450 ms.

Instead if I do this

  constructor() {
    effect(()=> {
      const moveSucceed = this.nodeMover.moveSucceed();
      if (validUpdate(moveSucceed)) {
        this.modalRef()?.hide();
      }
    });
   }

Is working fine, meaning effects reacts quicker than signalMethod.

[jits]

Hi @Massimiliano-Perelli,

[…] I have checked it but probably it does not fit for me because I need to do some async call and do a tapResponse inside its body as I usually do inside an effect. If I want to do so I think I should subscribe manually to the async method or so.

It sounds like you're best served with using RxJS/Observables for this, then, e.g. via rxMethod, and using toObservable on the signal.

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For the timing issue of signalMethod, I'd suggest you create a new discussion so we can focus on that separately (and it might get more attention from the maintainers and/or community).