AwesomeRouter: a cool Backbone.js router class

awesome_router.coffee

# AwesomeRouter: A class that I've been using throughout a few Backbone.js apps I've built.
#
# It adds 2 features: an event that gets fired when one calls `navigate` (aptly named
# "navigate"), so you can bind things to when a URL gets triggered. And a "before filter"
# method `before`, which you can use to run things before every a route gets triggered.
#
# This could easily be extended to have after filters too, or to only trigger a route
# upon @before returning something that's not false.

class AwesomeRouter extends Backbone.Router  
  initialize : ->
    if _.isFunction(@before)
      _super = Backbone.history.loadUrl
      before = @before
      router = @
      Backbone.history.loadUrl = ->
        before.call(router)
        router.trigger 'navigate'
        _super.apply(@, arguments)

# Usage:
class MyRouter extends AwesomeRouter
  routes :
    '/' : 'home'

  before : ->
    alert 'moo'

  home : ->
    console.log "Bet you saw me alert 'moo' just now"