effex

This package allows you to easily describe side effects in your reducer, rather than middleware. This allows you to pass local reducer state to your side effects.

import { createStore, compose, applyMiddleware } from "redux";
import { combineReducers, createStoreWithEffects } from "effex";
import * as reducers from "./reducers";
import middleware from "./middleware";
 
// create side-effect aware reducer
const reducer = combineReducers(reducers);
 
// create side-effect aware store
const enhancer = compose(
  applyMiddleware(middleware),
  createStoreWithEffects()
);
 
const store = createStore(reducer, preloadedState, enhancer);

import { combineReducers, createStateWithEffects } from "effex";
import { USER_LOGGED_IN, USER_TOKEN_STORED, userTokenStored } from "./actions";
 
// side effects perform async actions and may return an action to be dispatched
async function storeUserToken(token) {
  await SecureStorage.setItem("USER_TOKEN", token);
 
  return userTokenStored(token);
}
 
// side effects can use other side effects
async function clearUserToken() {
  return storeUserToken(null);
}
 
// declare your side effects in your reducer
// this gives you access to the action payload and local state
export default function tokenReducer(state = null, action) {
  switch (action.type) {
    case USER_LOGGED_IN:
      return createStateWithEffects(state, () => storeUserToken(action.payload.token));
 
    case USER_LOGGED_OUT:
      return createStateWithEffects(state, clearUserToken);
 
    case USER_TOKEN_STORED:
      return action.payload;
 
    default:
      return state;
  }
}