merb-assets
Provides extra functionality related to assets:
# Assets bundling. # Assets hosts. # Helpers to add asset links to views. # Deployment-time assets processing (for instance, with YUI Compressor).
Quick overview of the API
# asset_path generates path for asset taking type and name.
# UniqueAssetPath class handles generation of paths using subdomains. # AbstractAssetBundler is the base asset bundlers class.
# auto_link generates conventional asset tags based on controller/action. # link_to creates anchor tag (a tag). # image_tag creates img tag. # escape_js escapes JavaScript. # js method translates object into JSON. # require_js is smart(-er) way to do includes just once per page no matter how many times partial use it. # require_css is like require_js but for JavaScript. # js_include_tag is used when you need to include script tag with bundling. # css_include_tag works like js_include_tag but for stylesheets. # include_required_js generates script tags for previously included files. # include_required_css generates link tags for previously included files.
# uniq_js_path generates a script tag for path with asset subdomain. # uniq_css_path generates a link tag for path with asset subdomain.
Examples
auto_link to include asset tags using convention:
We want all possible matches in the FileSys up to the action name
Given: controller_name = "namespace/controller"
action_name = "action"
If all files are present should generate link/script tags for:
namespace.(css|js)
namespace/controller.(css|js)
namespace/controller/action.(css|js)
link_to and image_tag to make anchor and image tags:
image_tag('foo.gif')
# => <img src='/images/foo.gif' />
image_tag('foo.gif', :class => 'bar')
# => <img src='/images/foo.gif' class='bar' />
image_tag('foo.gif', :path => '/files/')
# => <img src='/files/foo.gif' />
image_tag('http://test.com/foo.gif')
# => <img src="http://test.com/foo.gif">
image_tag('charts', :path => '/dynamic/')
or
image_tag('/dynamic/charts')
# => <img src="/dynamic/charts">
link_to("The Merb home page", "http://www.merbivore.com/")
# => <a href="http://www.merbivore.com/">The Merb home page</a>
link_to("The Ruby home page", "http://www.ruby-lang.org", {'class' => 'special', 'target' => 'blank'})
# => <a href="http://www.ruby-lang.org" class="special" target="blank">The Ruby home page</a>
link_to p.title, "/blog/show/#{p.id}"
# => <a href="/blog/show/13">The Entry Title</a>
uniq_css_tag and uniq_js_tag for paths with asset subdomains:
uniq_css_tag("my")
#=> <link href="http://assets2.my-awesome-domain.com/stylesheets/my.css" type="text/css" />
uniq_js_tag("my")
#=> <script type="text/javascript" src="http://assets2.my-awesome-domain.com/javascripts/my.js"></script>
uniq_js_path("my")
#=> "http://assets2.my-awesome-domain.com/javascripts/my.js"
uniq_js_path(["admin/secrets","home/signup"])
#=> ["http://assets2.my-awesome-domain.com/javascripts/admin/secrets.js",
"http://assets1.my-awesome-domain.com/javascripts/home/signup.js"]
re_js and require_css, include_required_js and include_requried_css quire assets in parts/partials just once:
In your application layout:
js_include_tag :prototype, :lowpro, :bundle => :base
In your controller layout:
require_js :bundle => :posts
The require_js method can be used to require any JavaScript file anywhere
in your templates. Regardless of how many times a single script is
included with require_js, Merb will only include it once in the header.
# File: app/views/layouts/application.html.erb
<html>
<head>
<%= include_required_js %>
<%= include_required_css %>
</head>
<body>
<%= catch_content :layout %>
</body>
</html>
# File: app/views/whatever/_part1.herb
<% require_js 'this' -%>
<% require_css 'that', 'another_one' -%>
# File: app/views/whatever/_part2.herb
<% require_js 'this', 'something_else' -%>
<% require_css 'that' -%>
# File: app/views/whatever/index.herb
<%= partial(:part1) %>
<%= partial(:part2) %>
# Will generate the following in the final page...
<html>
<head>
<script src="/javascripts/this.js" type="text/javascript"></script>
<script src="/javascripts/something_else.js" type="text/javascript"></script>
<link href="/stylesheets/that.css" media="all" rel="Stylesheet" type="text/css"/>
<link href="/stylesheets/another_one.css" media="all" rel="Stylesheet" type="text/css"/>
</head>
.
.
.
</html>
# my_action.herb has a call to require_css 'style'
# File: layout/application.html.erb
include_required_css
# => <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css"/>
# my_action.herb has a call to require_css 'style', 'ie-specific'
# File: layout/application.html.erb
include_required_css
# => <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css"/>
# <link href="/stylesheets/ie-specific.css" media="all" rel="Stylesheet" type="text/css"/>
# my_action.herb has a call to require_js 'jquery'
# File: layout/application.html.erb
include_required_js
# => <script src="/javascripts/jquery.js" type="text/javascript"></script>
# my_action.herb has a call to require_js 'jquery', 'effects', 'validation'
# File: layout/application.html.erb
include_required_js
# => <script src="/javascripts/jquery.js" type="text/javascript"></script>
# <script src="/javascripts/effects.js" type="text/javascript"></script>
# <script src="/javascripts/validation.js" type="text/javascript"></script>
<% require_css('style') %>
# A subsequent call to include_required_css will render...
# => <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css"/>
<% require_css('style', 'ie-specific') %>
# A subsequent call to include_required_css will render...
# => <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css"/>
# <link href="/stylesheets/ie-specific.css" media="all" rel="Stylesheet" type="text/css"/>
<% require_js 'jquery' %>
# A subsequent call to include_required_js will render...
# => <script src="/javascripts/jquery.js" type="text/javascript"></script>
<% require_js 'jquery', 'effects' %>
# A subsequent call to include_required_js will render...
# => <script src="/javascripts/jquery.js" type="text/javascript"></script>
# <script src="/javascripts/effects.js" type="text/javascript"></script>
css_include_tag and js_include_tag that do not use asset subdomains:
css_include_tag 'style'
# => <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css" charset="utf-8" />
css_include_tag 'style.css', 'layout'
# => <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css" charset="utf-8" />
# <link href="/stylesheets/layout.css" media="all" rel="Stylesheet" type="text/css" charset="utf-8" />
css_include_tag :menu
# => <link href="/stylesheets/menu.css" media="all" rel="Stylesheet" type="text/css" charset="utf-8" />
css_include_tag :style, :screen
# => <link href="/stylesheets/style.css" media="all" rel="Stylesheet" type="text/css" charset="utf-8" />
# <link href="/stylesheets/screen.css" media="all" rel="Stylesheet" type="text/css" charset="utf-8" />
css_include_tag :style, :media => :print
# => <link href="/stylesheets/style.css" media="print" rel="Stylesheet" type="text/css" charset="utf-8" />
css_include_tag :style, :charset => 'iso-8859-1'
# => <link href="/stylesheets/style.css" media="print" rel="Stylesheet" type="text/css" charset="iso-8859-1" />
js_include_tag 'jquery'
# => <script src="/javascripts/jquery.js" type="text/javascript"></script>
js_include_tag 'moofx.js', 'upload'
# => <script src="/javascripts/moofx.js" type="text/javascript"></script>
# <script src="/javascripts/upload.js" type="text/javascript"></script>
js_include_tag :effects
# => <script src="/javascripts/effects.js" type="text/javascript"></script>
js_include_tag :jquery, :validation
# => <script src="/javascripts/jquery.js" type="text/javascript"></script>
# <script src="/javascripts/validation.js" type="text/javascript"></script>
Utility methods examples
uniq_css_path("my")
#=> "http://assets2.my-awesome-domain.com/stylesheets/my.css"
uniq_css_path(["admin/secrets","home/signup"])
#=> ["http://assets2.my-awesome-domain.com/stylesheets/admin/secrets.css",
"http://assets1.my-awesome-domain.com/stylesheets/home/signup.css"]
uniq_path("/javascripts/my.js","/javascripts/my.css")
#=> ["http://assets2.my-awesome-domain.com/javascripts/my.js", "http://assets1.my-awesome-domain.com/javascripts/my.css"]
uniq_path(["/javascripts/my.js","/stylesheets/my.css"])
#=> ["http://assets2.my-awesome-domain.com/javascripts/my.js", "http://assets1.my-awesome-domain.com/stylesheets/my.css"]
uniq_path(%w(/javascripts/my.js /stylesheets/my.css))
#=> ["http://assets2.my-awesome-domain.com/javascripts/my.js", "http://assets1.my-awesome-domain.com/stylesheets/my.css"]
uniq_path('/stylesheets/somearbitrary.css')
#=> "http://assets3.my-awesome-domain.com/stylesheets/somearbitrary.css"
uniq_path('/images/hostsexypicture.jpg')
#=>"http://assets1.my-awesome-domain.com/images/hostsexypicture.jpg"