A lightweight middleware to sync your redux state across browser tabs. It will listen to the Broadcast Channel and dispatch exactly the same actions dispatched in other tabs to keep the redux state in sync.
It syncs your redux store across tabs with very minimal configuration.
Thanks to BroadcastChannel, we now have a more efficient way to communicate between tabs instead of using any type of local storage. However, Not all the browsers support BroadcastChannel API for now. So I used pubkey's BroadcastChannel to find the best way to communicate between tabs for redux-state-sync. pubkey's BroadcastChannel will make sure that the communication between tabs always works.
Install with npm.
npm install --save redux-state-sync
Install with yarn
yarn add redux-state-sync
Install with npm.
npm install --save-dev @types/redux-state-sync
Install with yarn
yarn add --dev @types/redux-state-sync
Types are defined here
Please take note that BroadcastChannel can only send data that is supported by the structured clone algorithm (Strings, Objects, Arrays, Blobs, ArrayBuffer, Map), so you need to make sure that the actions that you wanna send to other tabs doesn't include any functions in the payload.
If you are using redux-persist, you may need to blacklist some of the actions that is triggered by redux-persist. e.g. persist/PERSIST, persist/REHYDRATE, etc.
Create the state sync middleware with config:
import { createStore, applyMiddleware } from 'redux';
import { createStateSyncMiddleware, initMessageListener } from 'redux-state-sync';
const config = {
// TOGGLE_TODO will not be triggered in other tabs
blacklist: ['TOGGLE_TODO'],
};
const middlewares = [createStateSyncMiddleware(config)];
const store = createStore(rootReducer, {}, applyMiddleware(...middlewares));
// this is used to pass store.dispatch to the message listener
initMessageListener(store);initMessageListener is a new function to fix the bug that if the other tab not triggering any action on first load, it cannot receive any messages.
Init new tabs with existing state:
- Use initStateWithPrevTab to get existing state from other tabs
import { createStore, applyMiddleware } from 'redux';
import { createStateSyncMiddleware, initStateWithPrevTab } from 'redux-state-sync';
const config = {
// TOGGLE_TODO will not be triggered in other tabs
blacklist: ['TOGGLE_TODO'],
};
const middlewares = [createStateSyncMiddleware(config)];
const store = createStore(rootReducer, {}, applyMiddleware(...middlewares));
// init state with other tabs
initStateWithPrevTab(store);
// initMessageListener(store);- Wrap your root reducer with
withReduxStateSync
import { withReduxStateSync } from 'redux-state-sync';
const rootReducer = combineReducers({
todos,
visibilityFilter,
});
export default withReduxStateSync(rootReducer);Note: ignore this if you are using redux-persist, because you will always inite your app with the state in the storage. However, if you don't want to persist the state in the storage and still want to init new tabs with opening tabs' state, you can follow the example above.
Unique name for Broadcast Channel
type: String
default: "redux_state_sync"
const config = {
channel: 'my_broadcast_channel',
};
const middlewares = [createStateSyncMiddleware(config)];A function to let you filter the actions as you wanted.
type: Function
default: null
const config = {
// All actions will be triggered in other tabs except 'TOGGLE_TODO'
predicate: action => action.type !== 'TOGGLE_TODO',
};
const middlewares = [createStateSyncMiddleware(config)];A list of action types that you don't want to be triggered in other tabs.
type: ArrayOf(<String>)
default: []
const config = {
// All actions will be triggered in other tabs except 'TOGGLE_TODO'
blacklist: ['TOGGLE_TODO'],
};
const middlewares = [createStateSyncMiddleware(config)];Only actions in this list will be triggered in other tabs.
type: ArrayOf(<String>)
default: []
const config = {
// Only 'TOGGLE_TODO' will be triggered in other tabs
whitelist: ['TOGGLE_TODO'],
};
const middlewares = [createStateSyncMiddleware(config)];Warning: You should only use one of the option to filter your actions. if you have all 3 options predicate, blacklist, and whitelist, only one will be effective and the priority is predicate > blacklist > whitelist.
Redux-state-sync is using BroadcastChannel to comunicate between tabs. broadcastChannelOption is the option passed to broadcastChannel when we creating the channel.
type: Object
default: null
const config = {
// Only 'TOGGLE_TODO' will be triggered in other tabs
whitelist: ['TOGGLE_TODO'],
// enforce a type, oneOf['native', 'idb', 'localstorage', 'node']
broadcastChannelOption: { type: 'localstorage' },
};
const middlewares = [createStateSyncMiddleware(config)];Please check the example_immutable folder.
Prepare the initial state for sending to other tabs.
type: Function
default: state => state
const config = {
// Map immutable object to js
prepareState: state => state.toJS(),
};
const middlewares = [createStateSyncMiddleware(config)];Reconcile the incoming state from other tabs with the existing state.
type: Function
default: (prevState, nextState) => nextState
const config = {
// Overwrite existing state with incoming state
receiveState: (prevState, nextState) => nextState,
};
const middlewares = [createStateSyncMiddleware(config)];import { combineReducers } from 'redux-immutable';
import { withReduxStateSync } from 'redux-state-sync';
const rootReducer = combineReducers({
todos,
visibilityFilter,
});
// Overwrite existing state with incoming state
export default withReduxStateSync(appReducer, (prevState, nextState) => nextState);