sprockets-helpers
=================
**Asset path helpers for Sprockets 2.x applications**
Sprockets::Helpers adds the asset_path helpers, familiar to Rails developers, to Sprockets 2.x assets and applications.
### Features
* Includes helpers for image, javascript, stylesheet, font, video, & audio assets.
* Automatically appends extension if necessary.
* Optionally outputs digest paths.
* Falls back to file paths in the public directory & adds cache busting timestamp.
Installation
------------
``` bash
$ gem install sprockets-helpers
```
Setup
-----
Let's build a simple Sinatra app using Sprockets and Sprockets::Helpers (See my fork of [sinatra-asset-pipeline](https://github.com/petebrowne/sinatra-asset-pipeline) for complete setup):
``` ruby
require 'sinatra/base'
require 'sprockets'
require 'sprockets-helpers'
class App < Sinatra::Base
set :sprockets, Sprockets::Environment.new(root)
set :assets_prefix, '/assets'
set :digest_assets, false
configure do
# Setup Sprockets
sprockets.append_path File.join(root, 'assets', 'stylesheets')
sprockets.append_path File.join(root, 'assets', 'javascripts')
sprockets.append_path File.join(root, 'assets', 'images')
# Configure Sprockets::Helpers (if necessary)
Sprockets::Helpers.configure do |config|
config.environment = sprockets
config.prefix = assets_prefix
config.digest = digest_assets
config.public_path = public_folder
end
end
helpers do
include Sprockets::Helpers
# Alternative method for telling Sprockets::Helpers which
# Sprockets environment to use.
# def assets_environment
# settings.sprockets
# end
end
get '/' do
erb :index
end
end
```
Usage in Assets
---------------
Simply requiring sprockets-helpers will add the asset path helpers to the Sprocket context, making them available within any asset. For example, a file `assets/javascripts/paths.js.erb`:
``` js+erb
var Paths = { railsImage: "<%= image_path 'rails.png' %>" };
```
Would be transformed into:
``` javascript
var Paths = { railsImage: '/assets/rails.png' };
```
Usage in the App
----------------
The helpers can also be used in the app itself. You just include the `Sprockets::Helpers` module and set Sprockets::Helpers.environment to the Sprockets environment to search for the assets. Alternatively you can define an #assets_environment method in the context of #asset_path, which returns a reference to the Sprockets environment (see above).
Now the following index file:
``` html+erb
Sinatra with Sprockets 2 (Asset Pipeline)
```
Would become:
``` html
Sinatra with Sprockets 2 (Asset Pipeline)
```
Even better, you can use #javascript_tag and #stylesheet_tag directly, which optionally handle the expansion of assets for debugging like Rails:
``` html+erb
Sinatra with Sprockets 2 (Asset Pipeline)
<%= stylesheet_tag 'application' %>
<%= javascript_tag 'application', :expand => true %>
```
Would become:
``` html
Sinatra with Sprockets 2 (Asset Pipeline)
```
Fallback to Public Directory
----------------------------
If the source is not an asset in the Sprockets environment, Sprockets::Helpers will fallback to looking for the file in the application's public directory. It will also append the cache busting timestamp of the file. For example:
Given an image, `public/images/logo.jpg`:
``` html+erb
```
Would become:
``` html
```
Manifest Usage
--------------
**New in 0.4**: Sprockets::Helpers will use the latest fingerprinted filename directly from a `manifest.json` file:
``` ruby
# ...
Sprockets::Helpers.configure do |config|
config.environment = sprockets
config.manifest = Sprockets::Manifest.new(sprockets, 'path/to/manifset.json')
config.prefix = assets_prefix
config.public_path = public_folder
end
# ...
```
Copyright
---------
Copyright (c) 2011 [Peter Browne](http://petebrowne.com). See LICENSE for details.
```
Would become:
``` html
```
Even better, you can use #javascript_tag and #stylesheet_tag directly, which optionally handle the expansion of assets for debugging like Rails:
``` html+erb
```
Would become:
``` html
```
Manifest Usage
--------------
**New in 0.4**: Sprockets::Helpers will use the latest fingerprinted filename directly from a `manifest.json` file:
``` ruby
# ...
Sprockets::Helpers.configure do |config|
config.environment = sprockets
config.manifest = Sprockets::Manifest.new(sprockets, 'path/to/manifset.json')
config.prefix = assets_prefix
config.public_path = public_folder
end
# ...
```
Copyright
---------
Copyright (c) 2011 [Peter Browne](http://petebrowne.com). See LICENSE for details.