redux-thunks

redux-thunks

Simple thunk creator for redux.

This is meant to smooth over the use of redux-thunk and redux-actions.

Installation

$ yarn add redux-thunks redux-thunk

or

$ npm install --save redux-thunks redux-thunk

Usage

This module is simply syntactic sugar for using redux-thunk with redux-actions. As such, it requires that you use the redux-thunk middleware.

Add redux-thunk middleware

import { createStore, applyMiddleware } from 'redux';
import thunk from 'redux-thunk';
import rootReducer from './reducers/index';

// Note: this API requires redux@>=3.1.0
const store = createStore(
  rootReducer,
  applyMiddleware(thunk)
);

Action definition

import { createAction, handleAction } from 'redux-actions';
import { createThunk } from 'redux-thunks';

export const setAmount = createAction('SET_AMOUNT');

export const incrementAsync = createThunk('INCREMENT_ASYNC', ({ dispatch, getState }, amount) => {
  doAsyncMath(getState(), amount).then(val => dispatch(setAmount(val)));
});

// the reducer is attached to the action that is actually dispatched
export default handleAction(setAmount, (state, payload) => payload, 0);

The context also receives the type name that you gave the thunk, which is useful to using createAction inside of the handler function, so that the action type only needs to be defined once, like so:

import { createAction, handleAction } from 'redux-actions';
import { createThunk } from 'redux-thunks';

export const resetAmountAsync = createThunk('RESET_AMOUNT', ({ dispatch, type }) => {
  // reset action. type is the value provided as the action type name, 'RESET_AMOUNT'
  const action = createAction(type);

  // read value from some async source and dispatch the reset action
  fetchAsyncValue().then(val => dispatch(action(val)));
});

// the reducer can use the exported thunk action directly
export default handleAction(resetAmountAsync, (state, payload) => payload, 0);

Use in component/container

dispatch(incrementAsync, 10); // adds 10
dispatch(resetAmountAsync); // resets the value

API

createThunk

createThunk('type', ({ dispatch, getState, type }, [...args]))

The syntax is very similar to that of createAction, and it smooths over the differences by similarly exposing a toString method on the thunk creator.

createThunk takes two arguments, a type name, and a function to execute when the action is dispatched. The first argument of the function will be a context object, with the following properties:

name	description
dispatch	Provided directly from redux-thunk, used to dispatch other actions
getState	Provided directly from redux-thunk, used to reach the current state
type	The type name of the action that was passed in as the first argument

Any additional arguments will be anything specified at the dispatch call site. It's expected that at least one other action will be dispatched from the handler function.

License

MIT © w33ble