Assets management for Ruby web projects
- Home page: http://lotusrb.org
- Community: http://lotusrb.org/community
- Guides: http://lotusrb.org/guides
- Mailing List: http://lotusrb.org/mailing-list
- API Doc: http://rdoc.info/gems/lotus-assets
- Bugs/Issues: https://github.com/lotus/assets/issues
- Support: http://stackoverflow.com/questions/tagged/lotus-ruby
- Forum: https://discuss.lotusrb.org
- Chat: http://chat.lotusrb.org
Lotus::Assets supports Ruby (MRI) 2+ and JRuby 1.7 (with 2.0 mode).
Add this line to your application's Gemfile:
gem 'lotus-assets'And then execute:
$ bundleOr install it yourself as:
$ gem install lotus-assetsThe framework offers assets specific helpers to be used in templates. They resolve one or multiple sources into corresponding HTML tags. Those sources can be the name of the local asset or an absolute URL.
Given the following template:
<!doctype HTML>
<html>
<head>
<title>Assets example</title>
<%= stylesheet 'reset', 'grid', 'main' %>
</head>
<body>
<!-- ... -->
<%= javascript 'https://code.jquery.com/jquery-2.1.1.min.js', 'application' %>
<%= javascript 'modals' %>
</body>
</html>It will output this markup.
<!doctype HTML>
<html>
<head>
<title>Assets example</title>
<link href="/assets/reset.css" type="text/css" rel="stylesheet">
<link href="/assets/grid.css" type="text/css" rel="stylesheet">
<link href="/assets/main.css" type="text/css" rel="stylesheet">
</head>
<body>
<!-- ... -->
<script src="https://code.jquery.com/jquery-2.1.1.min.js" type="text/javascript"></script>
<script src="/assets/application.js" type="text/javascript"></script>
<script src="/assets/modals.js" type="text/javascript"></script>
</body>
</html>Let's have a look at the corresponding Ruby code.
In this example we use ERb, but remember that Lotus::Assets is compatible with
all the rendering engines such as HAML, Slim, Mustache, etc..
require 'erb'
require 'lotus/assets'
require 'lotus/assets/helpers'
class View
include Lotus::Assets::Helpers
def initialize
@template = File.read('template.erb')
@engine = ERB.new(@template)
end
def render
@engine.result(binding)
end
end
View.new.render # => HTML markupFor advanced configurations, please have a look at
Lotus::Assets::Configuration.
For usage on lotus follow the instructions:
- In your
apps/web/application.rbincludelotus-assetsfiles:
require 'lotus/assets'- In your
application_layoutjust include the assets helpers
module Web
module Views
class ApplicationLayout
include Web::Layout
include Web::Assets::Helpers
end
end
end- After that you will be able to use
javascriptandstylesheetin your template.
Lotus::Assets can help you during the development process of your application.
It can manage multiple source directories for each asset type or run a
preprocessor for you.
Imagine to have your application's javascripts under app/assets/javascripts and that
those assets depends on a vendored version of jQuery.
require 'lotus/assets'
Lotus::Assets.configure do
compile true
sources << [
'app/assets',
'vendor/jquery'
]
endWhen from a template you do:
<%= javascript 'jquery', 'jquery-ui', 'login' %>Lotus::Assets looks at the defined sources and lazily copies those files
under public/assets (by default), before the markup is generated.
Your destination directory will have the following structure.
% tree public
public/
└── assets
├── jquery.js
├── jquery-ui.js
└── login.js
Please remember that sources are recursively looked up in order of declaration.
If in the example above we had a jquery.js under app/assets/javascripts/**/*.js
that file would be copied into the destination folder instead of the one under
vendor/jquery. The reason is because we declared app/assets/javascripts first.
Lotus::Assets is able to run assets preprocessors and lazily compile them
under public/assets (by default), before the markup is generated.
Imagine to have main.css.scss under app/assets/stylesheets and reset.css under
vendor/stylesheets.
The extensions structure is important.
The first one is mandatory and it's used to understand which asset type we are
handling: .css for stylesheets.
The second one is optional and it's for a preprocessor: .scss for Sass.
require 'sass'
require 'lotus/assets'
Lotus::Assets.configure do
compile true
sources << [
'assets',
'vendor/assets'
]
endWhen from a template you do:
<%= stylesheet 'reset', 'main' %>Your destination directory will have the following structure.
% tree public
public/
└── assets
├── reset.css
└── main.cssLotus::Assets uses Tilt to provide support for the most common preprocessors, such as Sass (including sassc-ruby), Less, ES6, JSX, CoffeScript, Opal, Handlebars, JBuilder.
In order to use one or more of them, be sure to include the corresponding gem into your Gemfile and require the library.
We strongly suggest to use EcmaScript 6 for your next project. It isn't fully supported yet by browser vendors, but it's the future of JavaScript.
As of today, you need to transpile ES6 code into something understandable by current browsers, which is ES5.
For this purpose we support Babel. Make sure to require 'lotus/assets/es6' to enable it.
Lotus::Assets ships with an executable (lotus-assets), which can be used to precompile assets and make them cacheable by browsers (via checksum suffix).
Let's say we have an application that has main file that requires the entire code (config/environment.rb), a gem that brings Ember.js code, and the following sources:
% tree .
├── apps
│ ├── admin
│ │ ├── assets
│ │ │ └── js
│ │ │ ├── application.js
│ │ │ └── zepto.js
# ...
│ ├── metrics
│ │ ├── assets
│ │ │ └── javascripts
│ │ │ └── dashboard.js
# ...
│ └── web
│ ├── assets
│ │ ├── images
│ │ │ └── bookshelf.jpg
│ │ └── javascripts
│ │ └── application.js
# ...
│ └── vendor
│ └── assets
│ └── javascripts
│ └── jquery.js
└── config
└── environment.rbIn order to deploy, we can run:
bundle exec lotus-assets --config=config/environment.rbIt will output:
tree public
public
├── assets
│ ├── admin
│ │ ├── application-28a6b886de2372ee3922fcaf3f78f2d8.js
│ │ ├── application.js
│ │ ├── ember-b2d6de1e99c79a0e52cf5c205aa2e07a.js
│ │ ├── ember-source-e74117fc6ba74418b2601ffff9eb1568.js
│ │ ├── ember-source.js
│ │ ├── ember.js
│ │ ├── zepto-ca736a378613d484138dec4e69be99b6.js
│ │ └── zepto.js
│ ├── application-d1829dc353b734e3adc24855693b70f9.js
│ ├── application.js
│ ├── bookshelf-237ecbedf745af5a477e380f0232039a.jpg
│ ├── bookshelf.jpg
│ ├── ember-b2d6de1e99c79a0e52cf5c205aa2e07a.js
│ ├── ember-source-e74117fc6ba74418b2601ffff9eb1568.js
│ ├── ember-source.js
│ ├── ember.js
│ ├── jquery-05277a4edea56b7f82a4c1442159e183.js
│ ├── jquery.js
│ └── metrics
│ ├── dashboard-7766a63ececc63a7a629bfb0666e9c62.js
│ ├── dashboard.js
│ ├── ember-b2d6de1e99c79a0e52cf5c205aa2e07a.js
│ ├── ember-source-e74117fc6ba74418b2601ffff9eb1568.js
│ ├── ember-source.js
│ └── ember.js
└── assets.jsonThis is a mode that can be activated via the configuration and it's suitable for production environments.
Lotus::Assets.configure do
digest true
endOnce turned on, it will look at public/assets.json, and helpers such as javascript will return a relative URL that includes the digest of the asset.
<%= javascript 'application' %><script src="/assets/application-d1829dc353b734e3adc24855693b70f9.js" type="text/javascript"></script>Developers can maintain gems that distribute assets for Lotus. For instance lotus-ember or lotus-jquery.
As a gem developer, you must add one or more paths, where the assets are stored inside the gem.
# lib/lotus/jquery.rb
Lotus::Assets.sources << '/path/to/jquery'- Make sure you have one of ExecJS supported runtime on your machine.
- Java 1.4+
bundle exec rake testLotus::Assets uses Semantic Versioning 2.0.0
- Fork it ( https://github.com/lotus/assets/fork )
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create new Pull Request
Copyright © 2014-2015 Luca Guidi – Released under MIT License