Ready to go rest engine with Piano (refactor and make gem soon)

index.haml

!!! 5
%html
  %head
    %title Arena: RESTful Piano
    = script "https://ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.min.js"
    = script "jquery.restful.js"
  %body
    - if flash?
      %output= flash
    %form(method="post" action="/")
      %input(name="id")/
      %input(name="value")/
      %button(type="submit") Save
    - items.each do |file|
      %dl
        %dt
          %a(href="/#{resource}:#{file}")= file
        %dd
          %a(method="delete" href="/#{resource}:#{file}") Delete
          %form(method="put" action="/#{resource}:#{file}")
            %input(name="value")/
            %button(type="submit") Update
    - if @content
      = @content

jquery.restful.coffee

$ ->
  $("form[method=put]").submit ->
    $.ajax 
      type: "PUT"
      url: $(this).attr "action"
      data: $(this).serialize()
      statusCode:
        201: (data, textStatus, xhr) ->
          window.location = xhr.getResponseHeader "Location"
    return false
  $("a[method=delete]").click ->
    $.ajax 
      type: "DELETE"
      url: $(this).attr "href"
      statusCode:
        201: (data, textStatus, xhr) ->
          window.location = xhr.getResponseHeader "Location"
    return false

Pianofile

require "json"
require "psych"

module Fast
  class File
    def append path, content
      ::File.open path, "a" do |handler|
        handler.write content
      end
    end
    
    def self.call *args
      if args.empty?
        File.new
      else
        ::File.read args.shift
      end
    end
  end
  
  def self.dir path, options = nil
    mkdir path unless Dir.exist? path
    if options
      if options[:extension]
        filtered = []
        Dir.entries(path).each do |entry|
          if entry.end_with? ".#{options[:extension]}"
            if options[:strip_extension]
              filtered << entry[0..-("#{options[:extension]}".length)-2]
            else
              filtered << entry 
            end
          end
        end
        return filtered
      end
    else
      Dir.entries path
    end
  end
  
  class From
    def yaml source
      if ::File.exist? source
        Psych.load_documents( file( source ) ).last
      else
        Psych.load source
      end
    end
  end
  
  def self.file *args
    Fast::File.call *args
  end
  
  def self.from
    Fast::From.new
  end
  
  private
    def self.mkdir path
      path.split("/").each do |part|
        route ||= part
        Dir.mkdir route unless route == "" || Dir.exist?( route )
        route += "/#{path}"
      end
      Dir.mkdir path
    end
end

delegate Fast, :dir, :file, :from

disable :etags
enable :sessions

post "/" do
  resource :index
  save_data params
  flash "Saved some data"
  redirect back, params.to_json
end

put %r{^/(.*?):(.+?)$} do |resource_text, item_text|
  resource resource_text.to_sym
  params["id"] = item_text
  params.delete "captures"
  
  save_data params
  flash "Updated #{item_text}"
  status 201
  headers \
    "Location" => "/#{resource}:#{item_text}"
  body params.to_json
end

delete %r{^/(.*?):(.+?)$} do |resource_text, item_text|
  resource_text = "index" if resource_text.nil?
  resource resource_text.to_sym
  delete_data item_text
  
  flash "Deleted #{item_text}"
  status 201
  headers \
    "Location" => "/#{resource}"
end

get %r{^/(.*?):(.+?)$} do |resource_text, item|
  resource_text = "index" if resource_text.nil?
  resource resource_text.to_sym
  @content = from.yaml "data/#{resource}/#{item}.yaml"
  try_haml resource
end

get %r{^/(.+?).js$} do |resource_text|
  content_type :js
  coffee resource_text.to_sym
end

get %r{^/(.+?).css$} do |resource_text|
  content_type :css
  sass resource_text.to_sym
end

get %r{^/(.+?)$} do |resource_text|
  resource resource_text.to_sym
  try_haml resource
end

get "/" do
  resource :index
  try_haml resource
end

before %r{^/(.*?)$} do |resource_text|
  resource resource_text.to_sym
end

helpers do
  def save_data data
    dir "data/#{resource}"
    file.append "data/#{resource}/" + data[:id] + ".yaml", data.to_yaml
  end
  
  def delete_data data
    ::File.unlink "data/#{resource}/#{data}.yaml"
  end
  
  def items
    if Dir.exists? "data/#{resource}"
      dir "data/#{resource}", :extension => :yaml, :strip_extension => true
    end
  end
  
  def resource symbol = nil
    if symbol
      session[:resource] = symbol
    else
      session[:resource]
    end
  end
  
  def flash?  
    session[:flash]
  end
  
  def flash data = nil
    if data
      session[:flash] = data
    else
      flash_text = session[:flash]
      session.delete :flash
      return flash_text
    end
  end
end