Slimmer provides rack middleware for applying a standard header and footer around pages returned by a ruby (rack) application.

It does this by taking the page rendered by the application, extracting the contents of a div with id 'wrapper' and inserting that into one of its templates. It also transfers various other details, such as meta, script, and style tags.

Use in a Rails app

Slimmer provides a Railtie so no configuration is necessary. By default it will use the Plek gem to look for the 'assets' host for the current environment.

If you want to use your own set of templates you will need to specify the appropriate host eg.

YourApp::Application.configure do
  config.slimmer.asset_host = 'http://your.server.somewhere'
end

it expects to find templates in a folder called 'templates' on that host.

Use elsewhere

Slimmer will work as standard rack middleware:

use Slimmer::App

or

use Slimmer::App, :asset_host => "http://my.alternative.host"

Specifying a template

A specific template can be requested by giving its name in the X-Slimmer-Template HTTP header

eg in a rails app

class MyController < ApplicationController
  def index
    headers['X-Slimmer-Template'] = 'homepage'
  end
end

There's also a macro style method:

class YourController < ApplicationController
  slimmer_template :admin
end

To get this, include Slimmer::Template in your controller:

class ApplicationController < ActionController::Base
  include Slimmer::Template
end

The name

Slimmer was extracted from a much larger project called 'skinner'. 'slimmer' referred to the size of its code compared to skinner (which also acted as an HTTP proxy and mixed in a few other concerns). Over time the codebase has grown a little, but the name stuck.