# Gon gem — get your Rails variables in your js ![Gon. You should try this. If you look closer - you will see an elephant.](https://github.com/gazay/gon/raw/master/doc/logo_small.png) [![Build Status](https://secure.travis-ci.org/gazay/gon.png)](http://travis-ci.org/gazay/gon) [![CodeClimate](https://codeclimate.com/github/gazay/gon.png)](https://codeclimate.com/github/gazay/gon) If you need to send some data to your js files and you don't want to do this with long way through views and parsing - use this force! Now you can easily renew data in your variables through ajax with [gon.watch](https://github.com/gazay/gon/wiki/Usage-gon-watch)! With [Jbuilder](https://github.com/rails/jbuilder), [Rabl](https://github.com/nesquena/rabl), and [Rabl-Rails](https://github.com/ccocchi/rabl-rails) support! For Sinatra available [gon-sinatra](https://github.com/gazay/gon-sinatra). For .Net MVC available port [NGon](https://github.com/brooklynDev/NGon). ## An example of typical use ### Very good and detailed example and reasons to use is considered in [railscast](http://railscasts.com/episodes/324-passing-data-to-javascript) by Ryan Bates When you need to send some start data from your controller to your js you might be doing something like this: 1. Write this data in controller(presenter/model) to some variable 2. In view for this action you put this variable to some objects by data attributes, or write js right in view 3. Then there can be two ways in js: + if you previously wrote data in data attributes - you should parse this attributes and write data to some js variable. + if you wrote js right in view (many frontenders would shame you for that) - you just use data from this js - OK. 4. You can use your data in your js And everytime when you need to send some data from action to js you do this. With gon you configure it firstly - just put in layout one tag, and add gem line to your Gemfile and do the following: 1. Write variables by ``` ruby gon.variable_name = variable_value # or new syntax gon.push({ :user_id => 1, :user_role => "admin" }) gon.push(any_object) # any_object with respond_to? :each_pair ``` 2. In your js you get this by ``` js gon.variable_name ``` 3. profit? With the `gon.watch` feature you can easily renew data in gon variables! Simply call `gon.watch` from your js file. It's super useful in modern web applications! ## Usage ### More details about configuration and usage you can find in [gon wiki](https://github.com/gazay/gon/wiki) Old readme available in [./README_old.md](https://github.com/gazay/gon/blob/master/README_old.md) `app/views/layouts/application.html.erb` ``` erb some title <%= include_gon %> ... ``` You can pass some [options](https://github.com/gazay/gon/wiki/Options) to `include_gon` method. You put something like this in the action of your controller: ``` ruby @your_int = 123 @your_array = [1,2] @your_hash = {'a' => 1, 'b' => 2} gon.your_int = @your_int gon.your_other_int = 345 + gon.your_int gon.your_array = @your_array gon.your_array << gon.your_int gon.your_hash = @your_hash gon.all_variables # > {:your_int => 123, :your_other_int => 468, :your_array => [1, 2, 123], :your_hash => {'a' => 1, 'b' => 2}} gon.your_array # > [1, 2, 123] gon.clear # gon.all_variables now is {} ``` Access the variables from your JavaScript file: ``` js alert(gon.your_int) alert(gon.your_other_int) alert(gon.your_array) alert(gon.your_hash) ``` ## gon.watch - renew your data easily! You can use gon for renewing your data without reloading pages and writing long js functions! It's really great for some live values. Supports `gon.watch.rabl` and `gon.watch.jbuilder` usage. [Instruction](https://github.com/gazay/gon/wiki/Usage-gon-watch) for usage gon.watch. ## Usage with Rabl You can write your variables assign logic to templates with [Rabl](https://github.com/nesquena/rabl). The way of writing Rabl templates is very clearly described in their repo. Profit of using Rabl with gon: 1. You can clean your controllers now! 2. Work with database objects and collections clearly and easyly 3. All power of Rabl 4. You can still be lazy and don't use common way to transfer data in js 5. And so on [Instruction](https://github.com/gazay/gon/wiki/Usage-with-rabl) for usage gon with Rabl. ## Usage with Rabl-Rails `gon.rabl` works with [rabl-rails](https://github.com/ccocchi/rabl-rails). Learn to write RABL the rabl-rails way [here](https://github.com/ccocchi/rabl-rails). Add gon and rabl-rails to your environment: ```ruby gem 'gon' gem 'rabl-rails' ``` Define a rabl template using rabl-rails syntax: ```rabl #app/views/users/show.rabl object :@user attributes :id, :name, :email, :location ``` Call gon.rabl in your controller ```ruby #app/controllers/users_controller.rb def show @user = User.find(params[:id]) gon.rabl end ``` ## Usage with Jbuilder Use gon with [Jbuilder](https://github.com/rails/jbuilder) as with [Rabl](https://guthub.com/nesquena/rabl): [Instruction](https://github.com/gazay/gon/wiki/Usage-with-jbuilder) for usage gon with Jbuilder. ## gon.global You can use gon for sending your data to js from anywhere! It's really great for some init data. [Instruction](https://github.com/gazay/gon/wiki/Usage-gon-global) for usage gon.global. ## Speed up Gon You can use any [JSON Engine](https://github.com/intridea/multi_json#supported-json-engines) you want. Gon uses `MultiJson` with autodetect mode, so all you need is just require your JSON library. ## Contributors * @gazay Special thanks to @brainopia, @kossnocorp and @ai. ## License The MIT License