Meteor Router

Meteor Router builds on page.js to provide reactive, filterable routing for Meteor applications.

Installation

Meteor Router can be installed with Meteorite. From inside a Meteorite-managed app:

$ mrt add router

Note that Router version 0.4.3 works with Meteor 0.5.8 and later, and 0.4.2 works with Meteor 0.5.7 and earlier.

API

Basics

To get the current page:

Meteor.Router.page();

This is a reactive variable which will trigger invalidations as the app changes pages. Usually, you'll just want to render the template that corresponds to the current page using the following helper that finds the template by name:

{{renderPage}}

It's common to render the inside page isolated from the layout:

{{#isolate}} {{renderPage}} {{/isolate}}

To define a route, simply specify the URL it matches and the name of the template it should render. If you want to get fancy, you can specify a reactive function that returns a template name. It will get repeatedly executed as its reactive dependencies change.

Be careful not to specify your routes inside the Meteor.startup function, or the routing won't work for the first load.

Meteor.Router.add({
  '/news': 'news',

  '/about': function() {
    if (Session.get('aboutUs')) {
      return 'aboutUs';
    } else {
      return 'aboutThem';
    }
  },

  '*': 'not_found'
});

To navigate to such a URL from in the app, either create a link which links to the URL (the router will intercept clicks and trigger relevant state changes), or call directly:

Meteor.Router.to('/news');

Note that this doesn't reload the app, it instead uses HTML5 pushState to change the URL whilst remaining loaded.

Route functions

When the route function is called, this corresponds to a page.js Context object, allowing you to do the following:

Meteor.Router.add({
  'posts/:id': function(id) {
    console.log('we are at ' + this.canonicalPath);
    console.log("our parameters: " + this.params);

    // access parameters in order a function args too
    Session.set('currentPostId', id);
    return 'showPost';
  }
});

Named Routes

If you specify your route with simply a template name, then you'll set up a named route. So instead of calling Meteor.Router.to('/news'), you can call Meteor.Router.to('news') (news is the name of the route). Additionally, that named route sets up the following:

• Meteor.Router.newsPath() -- which is /news in this case
• Meteor.Router.newsUrl() -- which is http://yourhost.com/news
• {{newsPath}} and {{newsUrl}} -- handlebars helpers

If you are using a routing function, you'll need to manually supply a route name, like so:

Meteor.Router.add({
  '/about': { as: 'about', to: function() {
    if (Session.get('aboutUs')) {
      return 'aboutUs';
    } else {
      return 'aboutThem';
    }
  }}
});

Meteor.Router.aboutPath(); // == '/about'

Additionally, you can provide a and property, which is a function that executes everytime the route executes (useful if your template is always the same, but you want to have some side effects):

Meteor.Router.add({
  '/posts/:_id': { to: 'showPost', and: function(id) {
    Session.set('currentPostId', id);
  }}
});

Meteor.Router.showPostPath(post) // == /posts/7

If your URL has named matches inside it, you can either pass in an object with those properties (e.g. post = {_id: 7} above), or you can pass the arguments in in order (e.g. showPostPath(7));

beforeRouting

Use Meteor.Router.beforeRouting = function() {} to set a callback to run before any routing function. Useful to reset session variables.

Filtering

The current system of filtering in this package is the equivalent of an after_filter in Rails. To add a filter which will render the correct template for a page which requires login:

Meteor.Router.filters({
  'checkLoggedIn': function(page) {
    if (Meteor.loggingIn()) {
      return 'loading';
    } else if (Meteor.user()) {
      return page;
    } else {
      return 'signin';
    }
  }
});

To turn the filter on, use one of:

// applies to all pages
Meteor.Router.filter('checkLoggedIn');

// applies to specific pages
Meteor.Router.filter('checkLoggedIn', {only: 'profile'});
Meteor.Router.filter('checkLoggedIn', {except: 'home'});

// accepts an array of pages
Meteor.Router.filter('checkLoggedIn', {only: ['profile', 'notifications'] });
Meteor.Router.filter('checkLoggedIn', {except: ['home', 'browse'] });

Note that filters build on reactivity. So the URL will not change but the user will see different pages as the state of the Meteor.user() property changes.

Server-side routing

The router also allows a very simple server side routing function with a similar API:

Meteor.Router.add('/posts/:id.xml', function(id) {
  return constructXMLForId(Posts.findOne(id));
});

Optionally you can also restrict the route by HTTP method:

Meteor.Router.add('/posts/:id.xml', 'GET', function(id) {
  return constructXMLForId(Posts.findOne(id));
});
Meteor.Router.add('/posts/:id.xml', 'DELETE', function(id) {
  Posts.remove(id);
  return [204, 'No Content'];
});

The arguments to the routing function are the parameters you've specified in your URL, and the this within the function is an object with three properties:

• this.params -- the list of parameters, page.js style
• this.request -- a Connect request
• this.response -- a Connect response (use this to e.g. set headers on your response).

Your routing function can return one of the following:

• a string, the body of the response
• a number, the http status code
• an array, in one of the following forms:
  • [body]
  • [statusCode, body]
  • [statusCode, headers, body], where headers is an object mapping header names to values.

Alternatively, rather than a routing function, you can just provide a fixed response:

Meteor.Router.add('/404', [404, "There's nothing here!"]);

The server side router adds the bodyParser middleware, enabling automatic parsing of JSON, Mutipart and URL encoded forms. You can tweak the Multipart parsing, i.e. changing the uploaded files destination directory:

Meteor.Router.configure({
  bodyParser: {
    uploadDir: 'uploads',
    hash: 'sha1'
  }
});

The configure() call MUST be put before any add() call, otherwise it will throw an error. For more information on options available, go to https://github.com/felixge/node-formidable

NOTE: Spark (meteor's template engine) does not currently run server side, so you are limited in what you can return here. Most likely you will want to return fairly simple things like JSON or XML documents, the construction of which is up to you.

Examples

Check out examples/simple-routed-app for an extremely simple example of a filtered routed app. (To run, use meteorite: cd examples/simple-routed-app; mrt run).

Additionally, you might want to read my blog post on page transitions in Meteor.

Internet explorer 8+ support

If you want the router to work in older version of Internet Explorer that don't support pushState, you can use the HTML5-History-API polyfill:

  mrt add HTML5-History-API

NOTE: Either do this before adding the router, or edit your app's .meteor/packages file to make sure it's listed before the router. This is a limitation that I'm working on.

Contributing

To run the tests, ensure that the router is checked out to a folder called router, and then simply run:

$ mrt test-packages router