url_dsl.rb

require 'open-uri'

# url dsl -- the ultimate url dsl!
#
# You just can't beat this:
#
#   $ irb -r url_dsl
#   >> include URLDSL
#   => Object
#   >> http://github.com/defunkt.json
#   => #<URLDSL::Request http://github.com/defunkt.json/>
#   >> puts http://github.com/defunkt.json
#   [{"repository":{"url":"http://github.com/defunkt/repl",
#   ... etc ...
#   => nil
#
# Or this:
#
#   >> require 'json'
#   => true
#   >> url = http://twitter.com/statuses/show/6592721580.json
#   => #<URLDSL::Request http://twitter.com/statuses/show/6592721580.json/>
#   >> JSON.parse(url.to_s)['text']
#   => "He nose the truth."
#


# Helper for using URLDSL in a Ruby file:
#
#   URLDSL do
#     puts http://twitter.com/brosner/status/6592721580.json
#   end
def URLDSL(&block)
  $urldsl_req = URLDSL::Request.new
  $urldsl_req.instance_eval(&block)
ensure
  $urldsl_req = nil
end

module URLDSL
  # This included hack is for `irb':
  #
  #   >> include URLDSL
  #   => Object
  #   >> http://github.com/api/v2/yaml/repos/show/schacon/grit
  #   => <yaml>

  def self.included(base)
    $urldsl_req = URLDSL::Request.new

    base.class_eval do
      def method_missing(*args, &block)
        $urldsl_req.send(*args, &block)
      end
    end
  end

  module SymbolHack
    def /(other = nil)
      return super unless other.is_a? Request
      other << "/"
      other
    end
  end
  Symbol.send :include, SymbolHack

  module NumberHack
    def method_missing(name, *args)
      $urldsl_req << self
      $urldsl_req << name
      self
    end
  end
  Integer.send :include, NumberHack

  class Request
    attr_accessor :protocol, :calls
    def initialize
      @calls = []
      @protocol = :http
    end

    def <<(method)
      @calls << method
    end

    def url
      build_url
    ensure
      @calls = []
    end

    def build_url
      protocol.to_s + '://' +
        @calls.join('.').
        gsub('./', '/').
        gsub('/.', '/').
        squeeze('/')
    end

    def to_s
      @to_s ||= open(url).read
    end

    def inspect
      "#<URLDSL::Request %s>" % build_url
    end

    def method_missing(name, *args)
      @to_s = nil

      if name.to_s =~ /https?/
        @protocol = name
      else
        self << name
      end

      args.each do |arg|
        self << arg unless arg.is_a?(Request) || @calls.include?(arg)
      end

      self
    end
  end
end


URLDSL do

  puts http://twitter.com/statuses/show/6592721580.json

  require 'yaml'
  url = http://github.com/api/v2/yaml/repos/show/schacon/grit
  puts YAML.load(url.to_s)['repository'][:name]

end if $0 == __FILE__