redux effects middleware

state-effects.js

// state/effects.js

/**
 * Internal dependencies
 */
import post from './post/effects';

export default [
	post
];

state-index.js

// state/index.js

/**
 * External dependencies
 */
import { createStore, applyMiddleware } from 'redux';
import effectsMiddleware from 'effects-middleware';

/**
 * Internal dependencies
 */
import reducer from './reducer';
import effects from './effects';

export default function configureStore() {
	return createStore( reducer, null, applyMiddleware( effectsMiddleware( effects ) ) );
}

state-posts-actions.js

// state/posts/actions.js

export function requestPost( postId ) {
	return {
		type: 'POST_REQUEST',
		postId
	};
}

export function receivePost( post ) {
	return {
		type: 'POST_RECEIVE',
		post
	};
}

state-posts-effects.js

// state/posts/effects.js

/**
 * Internal dependencies
 */
import { receivePost } from './actions';

export default {
	POST_REQUEST: async ( action, store ) => {
		const response = await fetch( `/posts/${ action.postId }` );
		const post = await response.json();
		store.dispatch( receivePost( post ) );
	}
};