ngrx observables.ts

// Reducer
export const examples = (state: any = [], {type, payload}) => {
  switch (type) {
    case 'ADD_EXAMPLES':
      console.log(state);
      return payload;
    case 'CREATE_EXAMPLES':
      return [...state, payload];
    case 'UPDATE_EXAMPLES':
      return state.map(example => {
        return example.token === payload.token ? Object.assign({}, example, payload) : example;
      });
    case 'DELETE_EXAMPLES':
      return state.filter(example => {
        return example.token !== payload.token;
      });
    default:
      return state;
  }
};

// Module import
imports : [
  StoreModule.forRoot({
    examples
  })
]

// Interface for store
export interface AppStore {
  examples: Example[];
  something: String[];
}

// Store service

@Injectable()
export class StoreService {

  examples: Observable<Example[]>;

  constructor(
    private http: HttpClient,
    private appStore: Store<AppStore>
  ) {
    this.examples = appStore.select(store => store.examples);
  }

  getSentences(paras: number = 5, filterText = '') {

    const apiUrl = `https://baconipsum.com/api/?type=meat-and-filler&paras=${paras}&format=json`;
    return this.http.get(apiUrl)
      .map(res => {
        return Object.values(res)
          .filter(item => item.includes(filterText))
          .map((item, i) => new Example(item, i));
      })
      .map((payload: Example[]) => {
        console.log('payload', payload);
        return {type: 'ADD_EXAMPLES', payload};
      })
      // Create the action and dispatch it to update the selected store
      .subscribe((action) => {
        console.log('action', action);
        this.appStore.dispatch(action);
      });
  }

}