README.md

redux-subscriber

This package allows you to subscribe to changes in any part of Redux state.

Installation

npm install redux-subscriber --save

Usage

store.js

import {createStore} from 'redux';
import initSubscriber from 'redux-subscriber';

const store = createStore(...);

// "initSubscriber" returns "subscribe" function, so you can use it
const subscribe = initSubscriber(store);

somewhere-else.js

// or you can just import "subscribe" function from the package
import {subscribe} from 'redux-subscriber';

const unsubscribe = subscribe('user.messages.count', state => {
    // do something
});

// if you want to stop listening to changes
unsubscribe();

Examples

• https://github.com/ivantsov/yandex-mail-notifier-chrome - real app that uses redux-subscriber

API

initSubscriber(store) (default export) - initialize redux-subscriber, so after that you can use subscribe method.

Options

• store - instance of Redux store.

Returns subscribe function.

subscribe(selector, callbackFunction) - subscribe callbackFunction to changes.

Options

• selector - string or function, string for which specified the part of state (e.g. user.message.count) to listen to, or function that accepts state as the first parameter and returns the state to listen to (i.e. a Redux selector function).
• callbackFunction - function which will be called when the part of state has changed. New state is passed as a parameter.

Returns unsubscribe function which can be called to unsubscribe from changes.