I am having an issue with the ngrx store not dispatching an action to the effect supposed to deal with it.
Here is the component that tries to dispatch:
I am using a later version of ngrx (7.4.0), so cartant's suggestion of:
.do((action) => console.log(`Received ${action.type}`))
should be...
... = this.actions.pipe(
tap((action) => console.log(`Received ${action.type}`)),
...
And in the end I discovered I had missed adding my new effects export to module, like:
EffectsModule.forRoot([AuthEffects, ViewEffects]), // was missing the ', ViewEffects'
Another possible reason is that if you used ng generate to create the module where you imported the Effects make sure it is imported in the App Module as the following command 'ng generate module myModule' will not add it to the app module.
This is not going to be a definitive answer, but, hopefully, it will be helpful.
Before you start:
@ngrx
packages (that are appropriate for the version of Angular you are using).If you've not done so already, you should have a look at the implementation of the Store - so that you make some educated guesses as to what could be going wrong. Note is that the Store
is pretty light. It's both an observable (using the state as its source) and an observer (that defers to the dispatcher).
If you look at store.dispatch you'll see that it's an alias for
store.next, which calls next
on the Dispatcher.
So calling:
this.store.dispatch(new StandardSigninAction(this.formStatus.form.value.credentials));
should just see an action emitted from the dispatcher.
The Actions observable that's injected into your effects is also pretty light. It's just an observable that uses the Dispatcher
as its source.
To look at the actions that are flowing through the effect, you could replace this:
@Effect()
standardSignin$: Observable<Action> = this.actions$
.ofType(session.ActionTypes.STANDARD_SIGNIN)
with this:
@Effect()
standardSignin$: Observable<Action> = this.actions$
.do((action) => console.log(`Received ${action.type}`))
.filter((action) => action.type === session.ActionTypes.STANDARD_SIGNIN)
ofType
is not an operator; it's a method, so to add do
-based logging, it needs to be replaced with a filter
.
With the logging in place, if you are receiving the action, there is something wrong with the effect's implementation (or maybe the action types' strings/constants aren't what you think they are and something is mismatched).
If the effect is not receiving the dispatched action, the most likely explanation would be that the store
through which you are dispatching the StandardSigninAction
is not that same store
that your effect is using - that is, you have a DI problem.
If that is the case, you should look at what differs from the other SessionEffects
that you say are working. (At least you have something working, which is a good place to start experimenting.) Are they dispatched from a different module? Is the module that dispatches StandardSigninAction
a feature module?
What happens if you hack one of the working SessionEffects
to replace its dispatched action with StandardSigninAction
? Does the effect then run?
Note that the questions at the end of this answer aren't questions that I want answered; they are questions that you should be asking yourself and investigating.
If you are using version 8, ensure you wrap each action with createEffect
.
Example:
Create$ = createEffect(() => this.actions$.pipe(...))
Your store's stream may be stopping because of either unhandled errors or - perhaps more confusingly - errors that seem 'handled' using .catch
that actually kill the stream without re-emitting a new Observable to keep things going.
For example, this will kill the stream:
this.actions$
.ofType('FETCH')
.map(a => a.payload)
.switchMap(query => this.apiService.fetch$(query)
.map(result => ({ type: 'SUCCESS', payload: result }))
.catch(err => console.log(`oops: ${err}`))) // <- breaks stream!
But this will keep things alive:
this.actions$
.ofType('FETCH')
.map(a => a.payload)
.switchMap(query => this.apiService.fetch$(query)
.map(result => ({ type: 'SUCCESS', payload: result }))
.catch(e => Observable.of({ type: 'FAIL', payload: e}))) // re-emit
This is true for any rxjs Observable btw, which is especially important to consider when broadcasting to multiple observers (like ngrx store does internally using an internal Subject
).