def url
      response = ::RestClient.post(Pxpay::Base.pxpay_request_url, post )
      response_text = ::Nokogiri::XML(response)
      if response_text.at_css("Request").attributes["valid"].value == "1"
        url = response_text.at_css("URI").inner_html
      else
        if Pxpay::Base.pxpay_user_id && Pxpay::Base.pxpay_key
          raise Pxpay::Error, response_text.at_css("Request").inner_html
        else
          raise Pxpay::MissingKey, "Your Pxpay config is not set up properly, run rails generate pxpay:install"
        end
      end
      return URI::extract(url).first.gsub("&amp;", "&")
    end
def url
      response = ::RestClient.post(Pxpay::Base.pxpay_request_url, post )
      response_text = ::Nokogiri::XML(response)
      if response_text.at_css("Request").attributes["valid"].value == "1"
        url = response_text.at_css("URI").inner_html
      else
        if Pxpay::Base.pxpay_user_id && Pxpay::Base.pxpay_key
          raise Pxpay::Error, response_text.at_css("Request").inner_html
        else
          raise Pxpay::MissingKey, "Your Pxpay config is not set up properly, run rails generate pxpay:install"
        end
      end
      return URI::extract(url).first.gsub("&amp;", "&")
    end
Create a new instance of Pxpay::Request
 Pxpay::Request.new( id, amount, options = {} )
 Current available options are:
 :currency_input,      currency for transaction, default is NZD, can be any of Pxpay::Base.currency_types
 :merchant_reference,  a reference field, default is the id.
 :email_address,       email address of user, optional.
 :token_billing,       boolean value, set to true to enable token billing.
 :billing_id,          optional billing_id field only used if token_billing is set to true.
 :txn_type,            can be set to :auth for Auth transaction, defaults to Purchase
 :url_success,         Success URL, can optionally be set globally via Pxpay::Base.url_success=
 :url_failure,         Failure URL, can optionally be set globally via Pxpay::Base.url_failure=
 :txn_data1,           Optional data
 :txn_data2,           Optional data
 :txn_data3,           Optional data
 :txn_data4,           Optional data
 :opt,                 Optional data
 Get the redirect URL from Payment Express