caremyway-client/src/store/index.js

import { createStore, applyMiddleware, compose } from "redux";
import createSagaMiddleware from "redux-saga";
import { createLogger } from "redux-logger";
import rootReducer from "../reducers";
import rootSaga from "../sagas";

export default function configureStore(initialState = {}) {
  const sagaMiddleware = createSagaMiddleware();
  const middlewares = [sagaMiddleware];
  if (process.env.NODE_ENV === "development" && process.env.REACT_APP_REDUX_LOGGING) {
    middlewares.push(createLogger());
  }

  const enhancers = [applyMiddleware(...middlewares)];
  const store = createStore(rootReducer, initialState, compose(...enhancers));

  // Extensions
  store.asyncReducers = {}; // Async reducer registry
  sagaMiddleware.run(rootSaga);

  return store;
}