class Rack::JQueryUI

jQuery CDN script tags and fallback in one neat package.

Constants

DEFAULT_OPTIONS

Default options hash for the middleware.

FALLBACK

This javascript checks if the jQuery-UI object has loaded. If not, that most likely means the CDN is unreachable, so it uses the local minified jQuery.

FALLBACK_PATH

path to the fallback script

JQUERY_UI_FILE_NAME

The usual file name.

JQUERY_UI_VERSION

version of jQuery-UI script.

JQUERY_UI_VERSION_DATE

This is the release date of the jQuery file, it makes an easy “Last-Modified” date for setting the headers around caching. TODO remember to change Last-Modified with each release!

VERSION

library version

Public Class Methods

cdn( env, options={} ) click to toggle source

@param [Hash] env The rack env hash. @param [Hash] options @option options [Symbol,false,nil] :organisation Choose which CDN to use, either :google, :microsoft or :media_temple, or :cloudflare. Pass in ‘false` to force use of the local jQuery script. `nil` will force choosing the default CDN. @option options [true, false] :debug If you need the unminified version from the CDN for debugging then pass this in. The unminified scripts aren’t included via the fallback to keep the library light, so this won’t change anything if fallback is used. @return [String] The HTML script tags to get the CDN. @example

# in a Haml file… (but could be any type of template)
# For the default
Rack::JQueryUI.cdn env

# Choose the organisation
Rack::JQueryUI.cdn env, :organisation => :cloudflare

# Raise an error if the organisation doesn't
# support this version of jQuery UI
Rack::JQueryUI.cdn env, :raise => true

# Use the unminified version from the CDN
Rack::JQueryUI.cdn env, :debug => true
# File lib/rack/jquery_ui.rb, line 65
def self.cdn( env, options={} )
  if env.nil? || env.has_key?(:organisation)
    fail ArgumentError, "The Rack::JQueryUI.cdn method needs the Rack environment passed to it, or at the very least, an empty hash."
  end
  raise = (opt = options[:raise]).nil? ?
            opt :
            (env["rack.jquery_ui.raise"] || false)

  organisation =  options[:organisation]
  if organisation.nil? # because false is valid
    organisation = env["rack.jquery_ui.organisation"] ||
                    :media_temple
  end

  unless organisation == false
    script_src = if organisation === :media_temple         
        CDNs::MEDIA_TEMPLE
      elsif organisation === :microsoft
        CDNs::MICROSOFT
      elsif organisation === :cloudflare
        CDNs::CLOUDFLARE
      elsif organisation === :google
        CDNs::GOOGLE
      else
        CDNs::MEDIA_TEMPLE
    end
      
    debug = options.fetch :debug, false
  
    script_src = "#{script_src[0..-7]}js" if debug
    "<script src='#{script_src}'></script>\n#{FALLBACK}"
  else
    "<script src='#{FALLBACK_PATH}'></script>"
  end
end
new( app, options={} ) click to toggle source

@param [#call] app @param [Hash] options @option options [String] :http_path If you wish the jQuery fallback route to be “/js/jquery-ui/1.10.1/jquery-ui.min.js” (or whichever version this is at) then do nothing, that’s the default. If you want the path to be “/assets/javascripts/jquery-ui/1.10.1/jquery-ui.min.js” then pass in ‘:http_path => “/assets/javascripts/#{Rack::JQueryUI::JQUERY_UI_VERSION}”. @note ***Don’t leave out the version number!***. The scripts provided by jQuery don’t contain the version in the filename like the jQuery scripts do, which means that organising them and sending the right headers back is bound to go wrong unless you put the version number somewhere in the route. You have been warned! @option options [TrueClass] :raise If one of the CDNs does not support then raise an error if it is chosen. Defaults to false. @example

# The default:
use Rack::JQueryUI
# With a different route to the fallback:
use Rack::JQueryUI, :http_path => "/assets/js/#{Rack::JQueryUI::JQUERY_UI_VERSION}"
# File lib/rack/jquery_ui.rb, line 119
def initialize( app, options={} )
  @app, @options  = app, DEFAULT_OPTIONS.merge(options)
  @http_path_to_jquery = ::File.join @options[:http_path], JQUERY_UI_FILE_NAME
  @raise = @options.fetch :raise, false
  @organisation = options.fetch :organisation, :media_temple
end

Public Instance Methods

_call( env ) click to toggle source

For thread safety @param (see call)

# File lib/rack/jquery_ui.rb, line 135
def _call( env )
  request = Rack::Request.new(env.dup)
  env.merge! "rack.jquery_ui.organisation" => @organisation
  env.merge! "rack.jquery_ui.raise" => @raise
  if request.path_info == @http_path_to_jquery
    response = Rack::Response.new
    # for caching
    response.headers.merge! caching_headers( "#{JQUERY_UI_FILE_NAME}-#{JQUERY_UI_VERSION}", JQUERY_UI_VERSION_DATE)

    # There's no need to test if the IF_MODIFIED_SINCE against the release date because the header will only be passed if the file was previously accessed by the requester, and the file is never updated. If it is updated then it is accessed by a different path.
    if request.env['HTTP_IF_MODIFIED_SINCE']
      response.status = 304
    else
      response.status = 200
      response.write ::File.read( ::File.expand_path "../../../vendor/assets/javascripts/jquery-ui/#{JQUERY_UI_VERSION}/#{JQUERY_UI_FILE_NAME}", __FILE__)
    end
    response.finish
  else
    @app.call(env)
  end
end
call( env ) click to toggle source

@param [Hash] env Rack request environment hash.

# File lib/rack/jquery_ui.rb, line 128
def call( env )
  dup._call env
end