import { createStore, applyMiddleware, compose } from 'redux'
import thunkMiddleware from 'redux-thunk'
import createLogger from 'redux-logger'

const loggerMiddleware = createLogger()

export default function configureStore(mainReducer) {
  return createStore(
    mainReducer,
    undefined,
    compose(
      applyMiddleware(
        thunkMiddleware,
        loggerMiddleware
       ),
      window.devToolsExtension ? window.devToolsExtension() : f => f)
    )
}

import { createStore, applyMiddleware, compose } from 'redux'
import thunkMiddleware from 'redux-thunk'
import { createLogger } from 'redux-logger'

const loggerMiddleware = createLogger()

export default function configureStore(mainReducer) {
  return createStore(
    mainReducer,
    undefined,
    compose(
      applyMiddleware(
        thunkMiddleware,
        loggerMiddleware
       ),
      window.devToolsExtension ? window.devToolsExtension() : f => f)
    )
}

Fix issue with redux-logger upgrade