freeCodeCamp/curriculum/challenges/english/03-front-end-libraries/redux/define-a-redux-action.english.md

id	title	challengeType	isRequired
5a24c314108439a4d403614d	Define a Redux Action	6	false

Description

Since Redux is a state management framework, updating state is one of its core tasks. In Redux, all state updates are triggered by dispatching actions. An action is simply a JavaScript object that contains information about an action event that has occurred. The Redux store receives these action objects, then updates its state accordingly. Sometimes a Redux action also carries some data. For example, the action carries a username after a user logs in. While the data is optional, actions must carry a type property that specifies the 'type' of action that occurred. Think of Redux actions as messengers that deliver information about events happening in your app to the Redux store. The store then conducts the business of updating state based on the action that occurred.

Instructions

Writing a Redux action is as simple as declaring an object with a type property. Declare an object action and give it a property type set to the string 'LOGIN'.

Tests

tests:
  - text: An action object should exist.
    testString: assert((function() { return typeof action === 'object' })(), 'An action object should exist.');
  - text: The action should have a key property type with value <code>LOGIN</code>.
    testString: assert((function() { return action.type === 'LOGIN' })(), 'The action should have a key property type with value <code>LOGIN</code>.');

Challenge Seed

// Define an action here:

Solution

const action = {
  type: 'LOGIN'
}