tstpierre / ddd-redux

Denver Dev Day - Maintainable JavaScript apps with REDUX

ddd-redux

Denver Dev Day - Maintainable JavaScript apps with REDUX

Follow up to a question regarding when to make API calls

Reducers should remain syncronous. So you certainly should not be making an API call there. Instead, you can take this approach:

• From your component, instead of dispatching an Action - you could call an injected Angular (in this example code base) to make the API call
• Centralized in that service, you can use standard promise handling. in your .then you can dispatch the Action that this specific API call has completed and communicate any payload as needed; likewise dispatch any Action to denote any error occuring
• This then runs through the pure reducers and can spit out the new state and let rxjs update the observing components

//angular service ommitted, must inject ngRedux to the service so it has the store and dispatch capability

loadCats(): void {  // you could add a loading: boolean to the state container
                    // to do some UI spinner/loading UX

    let self = this;

    psuedoCodeHttpClient.get('cat-api')
        .then((cats: Array)) => {
            // Here we can tie back the "angular way to make api calls" result
            // into the plain JS reducer and allow the state to change properly
            // and trigger observable updates

            self.ngRedux.dispatch(self.actions.catsFinishedLoading(cats));
        }
        .catch(() => { /* error action dispatch  */ }
    );
}