Add javascript variables and objects to rails projects without ugly js-erb stuffed in views.
Latest commit 6a928dc Jun 8, 2010 @ejschmitt updated documentation



This rails plugin will hide the messiness of passing variables from rails into javascript. It will automatically add the js needed to create a variable you define in rails, or add variables to objects.


Requires Json (require ‘json’)

./script/plugin install git://


in your controller:

jsvars[:loginPath] = login_path

  • Will create a global variable in the JS window object named ‘loginPath’ with the value you assigned.
jsvars[:myObject] = {:title => "My Page", :email => ""}
  • Adds the object variables that can be used as myObject.title & in the view javascipt.
  • This will add the object “myObject” if it does not exist, if it already does, only the variables will be added to the already existing object.
jsvars['myObj.myMeth.myValue'] = "myVar"
  • Adds the objects myObj, myMeth, myValue if they do not exist and defines the value of myObj.myMeth.myValue to myVar.
  • Only undefined objects will be added, so if myObj exists but myMeth and myVal do not, they will be added to the myObj object.

Example of extending an object:
In controller:

jsvars[:login] = {:path => '/login'}

in view:
    var login = {
        loginFuntion: function () {
            // ....
        specialVar: "My special Var"    

in JS:

login.loginFunction = function()
    login.specialVar = 'My special Var'
    login.path = '/login'

Getting the rails environment in javascript for all pages
In ApplicationController:

before_filter :set_js_env

def set_js_env jsvars[:railsEnv] = RAILS_ENV end


railsEnv = "development"

What this solves

This solves the mess of stuff like this:

    var loginPath = '<%= login_path %>';

(requiring the js to be left in an .html.erb file, or a .js.erb file)

to simple adding:

jsvars[:loginPath] = login_path

to the controller and allowing all js to be kept in .js files out of the html.
This can get especially messy with objects with a few rails defines attributes.


Copyright © 2010 Erick Schmitt, released under the MIT license.