react-logo/frontend/src/store/store.js

import { createStore, applyMiddleware, combineReducers, compose } from 'redux'
import createSagaMiddleware from 'redux-saga'
import rootSaga from '../sagas/root'
import { sessionReducer } from '../reducers/session.reducers';
import { messagesReducer } from '../reducers/messages.reducers';
import project from '../reducers/project'
import { usersReducer } from '../reducers/users.reducers';

const sagaMiddleware = createSagaMiddleware()

const rootReducer = combineReducers({
  session: sessionReducer,
  messages: messagesReducer,
  project,
  users: usersReducer,
});

const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;

export function configureStore(initialState = {}) {
    const store = createStore(
        rootReducer,
        initialState,
        composeEnhancers(
            applyMiddleware(sagaMiddleware)
        )
    )
    sagaMiddleware.run(rootSaga);
    return store;
}