React Nested Router

A complete routing library for React.

Features

Nested views mapped to nested routes
Modular construction of route hierarchy
Fully asynchronous transition hooks
Transition abort / redirect / retry
Dynamic segments
Query parameters
Links with automatic .active class when their route is active
Multiple root routes
Hash or HTML5 history URLs

Check out the examples directory to see how simple previously complex UI and workflows are to create.

Installation

npm install react-nested-router

Usage

This library only ships with CommonJS modules, so you'll need browserify or webpack or something that can load/bundle it.

var Route = require('react-nested-router').Route;

React.renderComponent((
  <Route handler={App}>
    <Route name="about" handler={About}/>
    <Route name="users" handler={Users}>
      <Route name="user" path="/user/:userId" handler={User}/>
    </Route>
  </Route>
), document.body);

Or if JSX isn't your jam:

React.renderComponent((
  Route({handler: App},
    Route({name: "about", handler: About}),
    Route({name: "users", handler: Users},
      Route({name: "user", path: "/user/:userId", handler: User})
    )
  )
), document.body);

When a Route is active, you'll get an instance of handler automatically rendered for you. When one of the child routes is active, you can render it with this.props.activeRoute in the parent all the way down the view hierarchy. This allows you to create nested layouts without having to wire it all up yourself. Link components create accessible anchor tags to route you around the application.

As an example, if the current path is /user/17, the following component will be rendered:

<App activeRoute={
  <Users activeRoute={<User params={{userId: 17}} />} />
} />

Each component will also receive a query prop equal to a dictionary of the current query params.

Here's the rest of the application:

var Link = require('react-nested-router').Link;

var App = React.createClass({
  render: function() {
    return (
      <div>
        <ul>
          <li><Link to="about">About</Link></li>
          <li><Link to="users">Users</Link></li>
          <li><Link to="user" userId="123">User 123</Link></li>
        </ul>
        {this.props.activeRoute}
      </div>
    );
  }
});

var About = React.createClass({
  render: function() {
    return <h2>About</h2>;
  }
});

var Users = React.createClass({
  render: function() {
    return (
      <div>
        <h2>Users</h2>
        {this.props.activeRoute}
      </div>
    );
  }
});

var User = React.createClass({
  render: function() {
    return <div>{this.props.params.userId}</div>
  }
});

Benefits of This Approach

Incredible screen-creation productivity - There is only one use-case when a user visits a route: render something. Every user interface has layers (or nesting) whether its a simple navbar or multiple levels of master-detail. Coupling nested routes to these nested views gets rid of a ton of work for the developer to wire all of it together when the user switches routes. Adding new screens could not get faster.
Immediate understanding of application structure - When routes are declared in one place, developers can easily construct a mental image of the application. It's essentially a sitemap. There's not a better way to get so much information about your app this quickly.
Code tractability - When a developer gets a ticket to fix a bug at as specific url they simply 1) look at the route config, then 2) go find the handler for that route. Every entry point into your application is represented by these routes.
URLs are your first thought, not an after-thought - With React Nested Router, you don't get UI on the page without configuring a url first. Fortunately, its wildly productive this way, too.

Related Modules

https://github.com/bjyoungblood/rnr-constrained-route - validate paths and parameters on route handlers.

API

Route (component)

Configuration component to declare your application's routes and view hierarchy.

Props

location - The method to use for page navigation when initializing the router. May be either "hash" to use URLs with hashes in them and the hashchange event or "history" to use the HTML5 history API. This prop is only ever used on the root route that is rendered into the page.

name - The name of the route, used in the Link component and the router's transition methods.

path - The path used in the URL, supporting dynamic segments. If left undefined, the path will be defined by the name. This path is always absolute from the URL "root", even if the leading slash is left off. Nested routes do not inherit the path of their parent.

handler - The component to be rendered when the route matches.

Children

Routes can be nested. When a child route matches, the parent route's handler will have an instance of the child route's handler available on this.props.activeRoute.

Examples

<Route handler={App}>
  <!-- path is automatically assigned to the name since it is omitted -->
  <Route name="about" handler={About}/>
  <Route name="users" handler={Users}>
    <!-- note the dynamic segment in the path -->
    <Route name="user" handler={User} path="/user/:id"/>
  </Route>
</Route>

Or w/o JSX:

Route({handler: App},
  Route({name: 'about', handler: About}),
  Route({name: 'users', handler: Users},
    Route({name: 'user', handler: User, path: '/user/:id'})
  )
);

Route Handler (user-defined component)

The value you pass to a route's handler prop is another component that is rendered to the page when that route is active. There are some special props and static methods available to these components.

Props

this.props.activeRoute - The active child route handler instance. Use it in your render method to render the child route.

this.props.params - When a route has dynamic segments like <Route path="users/:userId"/> the dynamic values are available at this.props.params.userId, etc.

this.props.query - The query parameters from the url.

Static Methods (Transition Hooks)

You can define static methods on your route handlers that will be called during route transitions.

willTransitionTo(transition, params) - Called when a route is about to render, giving you the opportunity to abort the transition. You can return a promise and the whole route hierarchy will wait for the promises to resolve before proceeding. This is especially useful for server-side rendering when you need to populate some data before the handler is rendered.

willTransitionFrom(transition, component) - Called when an active route is being transitioned out giving you an opportunity to abort the transition. The component is the current component, you'll probably need it to check its state to decide if you want to allow the transition.

Transition (object)

transition.abort() - aborts a transition

transition.redirect(to, params, query) - redirect to another route

transition.retry() - retrys a transition

Example

var Settings = React.createClass({
  statics: {
    willTransitionTo: function(transition, params) {
      return auth.isLoggedIn().then(function(loggedIn) {
        if (!loggedIn)
          return;
        transition.abort();
        return auth.logIn({transition: transition});
        // in auth module call `transition.retry()` after being logged in
      });
    },

    willTransitionFrom: function(transition, component) {
      if (component.formHasUnsavedData())) {
        if (!confirm('You have unsaved information, are you sure you want to leave this page?')) {
          transition.abort();
        }
      }
    }
  }

  //...
});

Link (Component)

Creates an anchor tag that links to a route in the application. Also gets the active class automatically when the route matches. If you change the path of your route, you don't have to change your links.

Properties

to - The name of the route to link to.

query - Object, Query parameters to add to the link. Access query parameters in your route handler with this.props.query.

[param] - Any parameters the route defines are passed by name through the link's properties.

Example

Given a route like <Route name="user" path="/users/:userId"/>:

<Link to="user" userId={user.id} params={{foo: bar}}>{user.name}</Link>
<!-- becomes one of these depending on your router and if the route is
active -->
<a href="/users/123?foo=bar" class="active">Michael</a>
<a href="#/users/123?foo=bar">Michael</a>

Top-Level Static Methods

The Router module has several top-level methods that may be used to navigate around the application.

transitionTo(routeName, [params[, query]]) - Programatically transition to a new route.

Router.transitionTo('user', {id: 10}, {showAge: true});
Router.transitionTo('about');

replaceWith(routeName, [params[, query]]) - Programatically replace current route with a new route. Does not add an entry into the browser history.

Router.replaceWith('user', {id: 10}, {showAge: true});
Router.replaceWith('about');

goBack() - Programatically go back to the last route and remove the most recent entry from the browser history.

Router.goBack();

Development

script/test will fire up a karma runner and watch for changes in the specs directory.
npm test will do the same but doesn't watch, just runs the tests.
script/build-examples does exactly that.

Commit subjects

When releasing, a changelog is created automatically, if your commit subject is important to the API or fixes a bug, please use one of the following prefixes:

[fixed] ...
[changed] ...
[added] ...
[removed] ...

Thanks, Ember

This library is highly inspired by the Ember.js routing API. In general, its a translation of the Ember router api to React. Huge thanks to the Ember team for solving the hardest part already.