Update README.md

Author: hoc081098

README.md

@@ -6,3 +6,104 @@
 <p align="center">
     <img src="https://github.com/hoc081098/rx_redux/blob/v2/images/logo.png?raw=true" alt="Logo" width="300"/>
 </p>
+
+## Effects with RxDart
+
+```dart
+RxReduxStore<HomeAction, HomeState> createStore(SearchUseCase searchUseCase) =>
+    RxReduxStore(
+      initialState: HomeState.initial(),
+      sideEffects: HomeSideEffects(searchUseCase)(),
+      reducer: (state, action) => action.reduce(state),
+      logger: rxReduxDefaultLogger,
+    );
+
+class HomeSideEffects {
+  final SearchUseCase _searchUseCase;
+
+  HomeSideEffects(this._searchUseCase);
+
+  List<SideEffect<HomeAction, HomeState>> call() => [
+        searchActionToTextChangedAction,
+        search,
+        nextPage,
+        retry,
+      ];
+
+  Stream<HomeAction> searchActionToTextChangedAction(
+    Stream<HomeAction> actions,
+    GetState<HomeState> getState,
+  ) =>
+      actions
+          .whereType<SearchAction>()
+          .debounceTime(const Duration(milliseconds: 500))
+          .map((action) => action.term.trim())
+          .where((term) => term.isNotEmpty)
+          .distinct()
+          .map((term) => TextChangedAction((b) => b..term = term));
+
+  Stream<HomeAction> search(
+    Stream<HomeAction> actions,
+    GetState<HomeState> getState,
+  ) =>
+      actions
+          .whereType<TextChangedAction>()
+          .map((action) => action.term)
+          .switchMap((term) => _nextPage(term, 1));
+
+  Stream<HomeAction> nextPage(
+    Stream<HomeAction> actions,
+    GetState<HomeState> getState,
+  ) {
+    final textChangedAction$ = actions.whereType<TextChangedAction>().debug();
+
+    final performLoadingNextPage = (LoadNextPageAction action) {
+      return Stream.value(getState())
+          .where((state) => state.canLoadNextPage)
+          .exhaustMap((state) => _nextPage(state.term, state.page + 1)
+              .takeUntil(textChangedAction$)
+              .debug());
+    };
+
+    return actions
+        .whereType<LoadNextPageAction>()
+        .exhaustMap(performLoadingNextPage);
+  }
+
+  Stream<HomeAction> retry(
+    Stream<HomeAction> actions,
+    GetState<HomeState> getState,
+  ) {
+    final textChangedAction$ = actions.whereType<TextChangedAction>().debug();
+
+    final performRetry = (RetryAction action) {
+      return Stream.value(getState())
+          .where((state) => state.canRetry)
+          .exhaustMap((state) => _nextPage(state.term, state.page + 1)
+              .takeUntil(textChangedAction$)
+              .debug());
+    };
+
+    return actions.whereType<RetryAction>().exhaustMap(performRetry);
+  }
+
+  Stream<HomeAction> _nextPage(String term, int nextPage) {
+    final loadingAction = SearchLoadingAction((b) => b
+      ..term = term
+      ..nextPage = nextPage);
+
+    return Rx.fromCallable(() => _searchUseCase(term: term, page: nextPage))
+        .map<HomeAction>(
+          (items) => SearchSuccessAction((b) => b
+            ..term = term
+            ..items.replace(items)),
+        )
+        .startWith(loadingAction)
+        .onErrorReturnWith(
+          (error) => SearchFailureAction((b) => b
+            ..error = error
+            ..term = term),
+        );
+  }
+}
+```