index.js

import "regenerator-runtime/runtime";
import { createStore, applyMiddleware, compose } from "redux";
import createSagaMiddleware from "redux-saga";

import rootReducer from "./rootReducer";
import rootSaga from "./rootSaga";

// ===== middleware 추가
const sagaMiddleware = createSagaMiddleware();
const middlewares = [sagaMiddleware];

// ===== store 생성
export const configureStore = (state = {}) => {
  const composeEnhancers =
    window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose; // redux-devtools-extension
  const store = createStore(
    rootReducer,
    composeEnhancers(applyMiddleware(...middlewares))
  );
  sagaMiddleware.run(rootSaga);
  return store;
};