Learning Redux

Creating the reducer

After defining our action types and action creator, we  need to handle the action in a reducer:

1. We will introduce a new session substate. Create a new file, src/reducers/session.js. We start by importing the LOGIN_SUCCESS action type:

import { LOGIN_SUCCESS } from '../actionTypes'

2. Then, we define the reducer function. The default state will be false (no session):

export default function sessionReducer (state = false, action) {

3. Next, we handle the LOGIN_SUCCESS action type and store the result in our session substate by returning it from the reducer:

  const { type, result } = action  if (type === LOGIN_SUCCESS) {    return result  }  return state}

4. Finally, we need to import and use our sessionReducer in the root reducer. ...