js_assets

Gem provides a helper asset_path in javascript.

Installation

Add gem to your Gemfile

gem 'js_assets'

And run bundle install.

The current version supports only Sprockets 3.x. For Sprockets 2.x use version 0.0.10

gem 'js_assets', '<= 0.0.10'

Usage

In your application.js

//= require app_assets

This directive adds the method asset_path in the global scope.

Get the path to the template app/assets/javascripts/rubrics/views/index.html in javascript:

var path = asset_path('rubrics/views/index.html')
// the function will return for development:
// /assets/rubrics/views/index.html
// and for production
// /assets/rubrics/views/index-5eb3bb250d5300736006c8944e436e3f.html

To automatically update app_assets.js when adding new files in app/assets, do the following steps. Add to Gemfile:

group :development do
  gem 'guard'
  gem 'guard-shell'
end

Add to Guardfile:

guard :shell do
    watch(%r{^app/assets/.*}) { `rm -rf tmp/cache` }
end

Run the command bundle exec to install the gems. Before starting to develop run guard:

$ bundle exec guard

Warning! This may adversely affect the rate of return assets list in the development environment. Since they will be compiled at each change.

Slim for AngularJS

For example we want to use templating Slim in AngularJS app. Let our templates will be in app/assets/webapp/. We make the following settings:

# config/application.rb
config.assets.paths << Rails.root.join('app', 'assets', 'webapp')

# config/initizlizers/assets_engine.rb
Rails.application.assets.register_engine('.slim', Slim::Template)

# config/environments/production.rb
config.assets.precompile += ['*.html']

Do not forget to connect a file in your application.js

//= require app_assets

Now for the template app/assets/webapp/blogs/edit.html.slim we can get a path depending on the environment:

var path = asset_path('blogs/edit.html')
// the function will return for development:
// /assets/blogs/edit.html
// and for production
// /assets/blogs/edit-5eb3bb250d5300736006c8944e436e3f.html

Settings

You can specify, for example in the initializer, which will be available in the helper asset_path, and which should be excluded.

To add a file to the list, use:

JsAssets::List.allow << '*.png'

To exclude:

JsAssets::List.exclude << '*.png'

Initially, the list is taken asset falling within the filter app/config/environments/production.rb

config.assets.precompile += ['*.html']

By default:

JsAssets::List.exclude = ["application.js"]
JsAssets::List.allow = ["*.html"]

Be careful! If the list of available JsAssets::List.allow get a file that is inserted directive require app_assets, recursion will occur as sprockets will calculate the md5-based content.

To determine which file name will be used (with md5 or not) use the option:

# Generate digests for assets URLs.
config.assets.digest = true

License

JsAssets is distributed under an MIT-style license. See LICENSE for details.