yahoo-yql-oauth.rb

####lib####
require 'net/http'
require 'hpricot'
require 'cgi'
require 'uri'
require 'cgi'
require 'openssl'
require 'base64'

module Chebyte
  module Yahoo
    class OauthUtil

      attr_accessor :consumer_key, :consumer_secret, :token, :token_secret, :req_method,
                    :sig_method, :oauth_version, :callback_url, :params, :req_url, :base_str

      def initialize
        @consumer_key = ''
        @consumer_secret = ''
        @token = ''
        @token_secret = ''
        @req_method = 'GET'
        @sig_method = 'HMAC-SHA1'
        @oauth_version = '1.0'
        @callback_url = ''
      end

      # openssl::random_bytes returns non-word chars, which need to be removed. using alt method to get length
      # ref http://snippets.dzone.com/posts/show/491
      def nonce
        Array.new( 5 ) { rand(256) }.pack('C*').unpack('H*').first
      end

      def percent_encode( string )

        # ref http://snippets.dzone.com/posts/show/1260
        return URI.escape( string, Regexp.new("[^#{URI::PATTERN::UNRESERVED}]") ).gsub('*', '%2A')
      end

      # @ref http://oauth.net/core/1.0/#rfc.section.9.2
      def signature
        key = percent_encode( @consumer_secret ) + '&' + percent_encode( @token_secret )

        # ref: http://blog.nathanielbibler.com/post/63031273/openssl-hmac-vs-ruby-hmac-benchmarks
        digest = OpenSSL::Digest::Digest.new( 'sha1' )
        hmac = OpenSSL::HMAC.digest( digest, key, @base_str )

        # ref http://groups.google.com/group/oauth-ruby/browse_thread/thread/9110ed8c8f3cae81
        Base64.encode64( hmac ).chomp.gsub( /\n/, '' )
      end

      # sort (very important as it affects the signature), concat, and percent encode
      # @ref http://oauth.net/core/1.0/#rfc.section.9.1.1
      # @ref http://oauth.net/core/1.0/#9.2.1
      # @ref http://oauth.net/core/1.0/#rfc.section.A.5.1
      def query_string
        pairs = []
        @params.sort.each { | key, val |
          pairs.push( "#{ percent_encode( key ) }=#{ percent_encode( val.to_s ) }" )
        }
        pairs.join '&'
      end

      # organize params & create signature
      def sign( parsed_url )

        @params = {
          'oauth_consumer_key' => @consumer_key,
          'oauth_nonce' => nonce,
          'oauth_signature_method' => @sig_method,
          'oauth_timestamp' => Time.now.to_i.to_s,
          'oauth_version' => @oauth_version
        }

        # if url has query, merge key/values into params obj overwriting defaults
        if parsed_url.query
          @params.merge! CGI.parse( parsed_url.query )
        end

        # @ref http://oauth.net/core/1.0/#rfc.section.9.1.2
        @req_url = parsed_url.scheme + '://' + parsed_url.host + parsed_url.path

        # create base str. make it an object attr for ez debugging
        # ref http://oauth.net/core/1.0/#anchor14
        @base_str = [
          @req_method,
          percent_encode( req_url ),

          # normalization is just x-www-form-urlencoded
          percent_encode( query_string )

        ].join( '&' )

        # add signature
        @params[ 'oauth_signature' ] = signature

        return self
      end
    end

    class GeoLoc
      def initialize(api_key, share_key)
        @o = OauthUtil.new
        @o.consumer_key    = api_key
        @o.consumer_secret = share_key
        @response = nil
      end

      def escape(string)
        CGI::escape(string)
      end

      def find_by_address(string)
        url = "http://query.yahooapis.com/v1/public/yql?q=SELECT%20centroid%20from%20geo.places%20WHERE%20text%3D'#{escape(string)}'&diagnostics=false"
        parsed_url = URI.parse( url )
        Net::HTTP.start( parsed_url.host ) do | http |
          req = Net::HTTP::Get.new "#{ parsed_url.path }?#{ @o.sign(parsed_url).query_string }"
          @response = Location.new(Hpricot.XML(http.request(req).read_body))
        end
      end

      def find(sql)
        url = "http://query.yahooapis.com/v1/public/yql?q=#{escape(sql)}"
        parsed_url = URI.parse( sql )
        Net::HTTP.start( parsed_url.host ) do | http |
          req = Net::HTTP::Get.new "#{ parsed_url.path }?#{ @o.sign(parsed_url).query_string }"
          @response = Location.new(Hpricot.XML(http.request(req).read_body))
        end
      end
    end

    class Location

      def initialize(response)
        @response = response
      end

      def latitude
        (@response/"centroid").each{|location| return (location/"latitude").text}
      end

      def longitude
        (@response/"centroid").each{|location| return (location/"longitude").text}
      end

      def coords
        "#{latitude}, #{longitude}"
      end
    end
  end
end

###USAGE####
Chebyte::Yahoo::GeoLoc.new(api_key, shared_key).find_by_address("100 Spear st, San Francisco, CA").coords #"37.779598, -122.420143"