Contents

require 'base64'
require 'hmac-sha1'

module FoodInfo
  module Adapters
    class FatSecret

      class Request
        HOST = 'http://platform.fatsecret.com/rest/server.api'
  
        # Returns the query string necessary to run the specified +method+
        # against the FatSecret API, using the +auth+ (+key+ and +secret+)
        # to sign it.
        #
        # If this class were accessed externally, I'd refactor it a bit
        # so it didn't require auth info to be passed on every request.
        def initialize(method, auth, optional_params = {})
          @auth          = auth
          @request_nonce = (0...10).map{65.+(rand(25)).chr}.join
          @request_time  = Time.now.to_i.to_s
          @http_method   = optional_params.delete(:http_method) || 'GET'

          @params = {
            :method => method,
            :format => 'json'
          }.merge(optional_params || {})
        end
  
        def signed_request
          "#{HOST}?#{make_query_string(query_params)}&oauth_signature=#{request_signature}"
        end

        
        protected

        def request_signature(token=nil)
          signing_key  = [@auth[:secret], token].join('&')
    
          sha = HMAC::SHA1.digest(signing_key, signature_base_string)
          Base64.encode64(sha).strip.oauth_escape
        end

        def signature_base_string
          [@http_method, HOST, make_query_string(query_params)].map(&:oauth_escape).join('&')
        end
  
        def make_query_string(pairs)
          sorted = pairs.sort{|a,b| a[0].to_s <=> b[0].to_s}
          sorted.collect{|p| p.join('=')}.join('&')
        end
  
        def query_params
          oauth_components.merge(@params)
        end
      
        def oauth_components
          {
            :oauth_consumer_key => @auth[:key],
            :oauth_signature_method => 'HMAC-SHA1',
            :oauth_timestamp => @request_time,
            :oauth_nonce => @request_nonce,
            :oauth_version => '1.0'
          }
        end

      end
  
    end
  end
end

Version data entries

7 entries across 7 versions & 1 rubygems

Version	Path
food_info-0.0.7	lib/food_info/adapters/fat_secret/request.rb
food_info-0.0.6	lib/food_info/adapters/fat_secret/request.rb
food_info-0.0.5	lib/food_info/adapters/fat_secret/request.rb
food_info-0.0.4	lib/food_info/adapters/fat_secret/request.rb
food_info-0.0.3	lib/food_info/adapters/fat_secret/request.rb
food_info-0.0.2	lib/food_info/adapters/fat_secret/request.rb
food_info-0.0.1	lib/food_info/adapters/fat_secret/request.rb