redux-simple-router

redux-simple-router

Redux is cool. react-router is neat. The problem is that react-router manages an important piece of your application state: the URL. If you are using redux, you want your app state to fully represent your UI; if you snapshotted the app state, you should be able to load it up later and see the same thing.

react-router automatically maps the current URL to a path down your component tree, and continually does so with any URL changes. This is very useful, but we really want to store this state in redux as well.

The entire state that we are interested in boils down to one thing: the URL. This is an extremely simple library that just puts the URL in redux state and keeps it in sync with any react-router changes. Additionally, you can change the URL via redux and react-router will change accordingly.

npm install redux-simple-router

Isn't there already redux-router?

redux-router is another project which solves the same problem. However, it's far more complex. Just look at this code: the whole thing is only 68 lines of JS. redux-router is much bigger and more complex.

That said, redux-router is a fine project and has features this doesn't provide. Use it if you like it better.

The differences between this and redux-router:

• Much smaller and simpler. You don't need to learn another library on top of everything else.
• We encourage direct access of react-router APIs. Need server-side rendering, or something else advanced? Just read react-router's docs.
• The piece of state is just a URL string, whereas redux-router stores the full location object from react-router.

This only depends on the history.listen function from react-router and the store.getState and store.subscribe functions from redux. It should be very future-proof with any versions of either libraries.

How to Use

The idea of this library is to use react-router's functionality exactly like its documentation tells you to. You can access all of its APIs in routing components. Additionally, you can use redux like you normally would, with a single app state and "connected" components. It's even possible for a single component to be both if needed.

This library provides a single point of synchronization: the routing.path piece of state which is the current URL. You can read it, and also change it with an action.

Here's some code:

const { createStore, combineReducers } = require('redux');
const { Provider } = require('react-redux');
const { Router, Route } = require('react-router');
const createBrowserHistory = require('history/lib/createBrowserHistory');
const { syncReduxAndRouter, routeReducer } = require('redux-simple-router');
const reducers = require('<project-path>/reducers');

const reducer = combineReducers(Object.assign({}, reducers, {
  routing: routeReducer
}));
const store = createStore(reducer);
const history = createBrowserHistory();

syncReduxAndRouter(history, store);

React.render(
  <Provider store={store}>
    <Router history={history}>
      <Route path="/" component={App}>
        <Route path="foo" component={Foo}/>
        <Route path="bar" component={Bar}/>
      </Route>
    </Router>
  </Provider>,
  document.getElementById('mount')
);

Now you can read from state.routing.path to get the URL. It's far more likely that you want to change the URL more often, however. You can use the updatePath action creator the we provide:

const { updatePath } = require ('redux-simple-router');

function MyComponent({ dispatch }) {
  return <Button onClick={() => dispatch(updatePath('/foo'))}/>;
}

This will change the state, which will trigger a change in react-router.

Additionally, if you want to respond to the path update action, just handle the UPDATE_PATH constant that we provide:

const { UPDATE_PATH } = require('redux-simple-router');

function update(state, action) {
  switch(action.type) {
  case UPDATE_PATH:
    // do something here
  }
}

API

syncReduxAndRouter(history, store, selectRouterState?)

Call this with a react-router and a redux store instance to install hooks that always keep both of them in sync. When one changes, so will the other.

Supply an optional function selectRouterState to customize where to find the router state on your app state. It defaults to state => state.routing, so you would install the reducer under the name "routing". Feel free to change this to whatever you like.

routeReducer

A reducer function that keeps track of the router state. You need to add this reducer to your app reducers when creating the store. The piece of state must be named routing

UPDATE_PATH

An action type that you can listen for in your reducers.

updatePath(path, noRouterUpdate)

An action creator that you can use to update the current URL. Just pass it a string like /foo/bar?param=5.

The noRouterUpdate, if true, will stop react-router from reacting to this and all future URL changes. Pass false to make it start reacting again. This is useful if replaying snapshots while using the forceRefresh option of the browser history which forces full reloads. It's a rare edge case.