By default, an ngrx/effect dispatches an action. If you want an effect to be ‘fire-and-forget’, all you need to do is add {dispatch: false} as an argument to the @Effects() decorator. From the @ngrx/effects docs: Observables decorated with the @Effect() decorator are expected to be a stream of actions to be dispatched. Pass { dispatch: … Read more
Its used as an optimization step for store slices selection. For example, if you return some heavy computation result for some store slice, then using createSelector will do memoization which means it will keep track of last input params to selector and if they are the same as current ones, it will return last result … Read more
I am new to RXJS but what about this. You can remove {dispatch: false} if you change the tap to a switchMap. @Effect({dispatch: false}) public waitForActions(): Observable<any> { const waitFor: string[] = [ SomeAction.EVENT_1, SomeAction.EVENT_2, SomeAction.EVENT_3, ]; return this._actions$ .pipe( ofType(…waitFor), distinct((action: IAction<any>) => action.type), bufferCount(waitFor.length), tap(console.log), ); }
(UPDATE: 02-07-2019: This post was getting dated–added the ‘store/ngrx’ pattern) So after looking into this further, when it comes to how best to communicate down and up a nested component chain, there seems to be really only two options — a Faustian bargain between: EITHER either pass @Input/@Output bindings up, down, and throughout the nested … Read more
Managed to solve this by adding StoreModule.forRoot({}), in the imports. StoreModule.forRoot should only be called once in the root of your project NgModule. If you wan’t to register a feature, use StoreModule.forFeature. Using forRoot registers the global providers needed for Store. Check the github discussion here on this issue. The above reason was stated in … Read more
After refactoring you moved map out of switchMap projection, so any error will close the outer stream. To keep both streams equivalent, you need to use pipe in the projection itself like that: import { EMPTY } from ‘rxjs’; // … @Effect() loadData$ = this.actions$ .ofType(LOAD_DATA) .pipe( map((action: LoadData) => action.payload), withLatestFrom(this.store.select(getCultureCode)), switchMap(([payload, cultureCode]) => … Read more
Its used with lazy loaded reducers. When you have (lazy loaded) feature modules and you want to register reducers within that module, then you use forFeature. Otherwise, in your AppModule you use forRoot.
I think you should read those two posts about Ngrx store: Angular Service Layers: Redux, RxJs and Ngrx Store – When to Use a Store And Why? Ngrx Store – An Architecture Guide If the first one explains the main issues solved by Ngrx Store, it also quote this statement from the React How-To “that … Read more