rest.rb

class RESTController < Controller
  def self.object_name=(object_name)
    @@object_name = object_name
  end

  def self.object_name
    @@object_name
  end

  # @api plugin
  def object_name
    @@object_name
  end

  def collection_name
    @@collection_name ||= "#{@@object_name}s"
  end

  def self.template_root=(template_root)
    @@template_root = template_root
  end

  def self.template_root
    @@template_root
  end

  # @api plugin
  def template_root
    @@template_root
  end

  def self.define_rest_method(method)
    define_method method do |&block|
      raise ArgumentError, "You have to provide a block" if block.nil?
      context[collection_name] = block.call
      render File.join(template_root, index)
    end
  end

  [:index, :show, :new, :edit].each(&:define_rest_method)

  def create(notice = "Created successfully", error = "Can't create", &block)
    raise ArgumentError, "You have to provide a block" if block.nil?
    object = block.call
    if object.save
      message[:notice] = notice
      redirect # TODO
    else
      message[:error] = error
      redirect # TODO
    end
  end

  def update(notice = "Updated successfully", error = "Can't update", &block)
    raise ArgumentError, "You have to provide a block" if block.nil?
    object = block.call
    if object.save
      message[:notice] = notice
      redirect # TODO
    else
      message[:error] = error
      redirect # TODO
    end
  end
end

class Posts < RESTController
  object_name :post
  template_root "blog/posts"

  def index(page)
    super do
      Post.paginate(page, 20)
    end
  end

  def show(id)
    super { Post.get(id) }
  end

  def new
    super { Post.new }
  end

  def edit(id)
    super { @post || Post.get(id) }
  end

  def create(post)
    notice = "Post create successfuly"
    error = "Saving failed"
    super(notice, error) do
      @post = Post.new(post)
    end
  end

  def update(id, post)
    super do
      @post = Post.attributes.merge!(post)
    end
  end
end

class MyCustomizedPosts < Posts
  def create(post)
    super(post)
  rescue Rango::Exceptions::Redirection
    redirect "/"
  end
end