Rename some private methods for consistency

Author: johnnyshields

lib/ruby_saml/xml/document_signer.rb

@@ -8,6 +8,9 @@ module DocumentSigner
 
       INC_PREFIX_LIST = '#default samlp saml ds xs xsi md'
 
+      # Returns a copy of the document with a signature added.
+      #
+      # @example The Signature is added following the Issuer node.
       # <Signature>
       #   <SignedInfo>
       #     <CanonicalizationMethod />
@@ -23,7 +26,6 @@ module DocumentSigner
       #   <KeyInfo />
       #   <Object />
       # </Signature>
-      # Returns a copy of the document with a signature added.
       def sign_document(document, private_key, certificate, signature_method = RubySaml::XML::RSA_SHA256, digest_method = RubySaml::XML::SHA256)
         noko = RubySaml::XML.safe_load_nokogiri(document.to_s)
 
@@ -32,23 +34,23 @@ def sign_document(document, private_key, certificate, signature_method = RubySam
 
       # Modifies an existing Nokogiri document to add a signature.
       def sign_document!(noko, private_key, certificate, signature_method = RubySaml::XML::RSA_SHA256, digest_method = RubySaml::XML::SHA256)
-        signature_element = build_signature_element(noko, private_key, certificate, signature_method, digest_method)
-        issuer_element = noko.at_xpath('//saml:Issuer', 'saml' => RubySaml::XML::NS_ASSERTION)
-        if issuer_element
-          issuer_element.after(signature_element)
+        signature_node = build_signature_node(noko, private_key, certificate, signature_method, digest_method)
+
+        if (issuer_node = noko.at_xpath('//saml:Issuer', 'saml' => RubySaml::XML::NS_ASSERTION))
+          issuer_node.after(signature_node)
         elsif noko.root.children.any?
-          noko.root.children.first.before(signature_element)
+          noko.root.children.first.before(signature_node)
         else
-          noko.root.add_child(signature_element)
+          noko.root.add_child(signature_node)
         end
 
         noko
       end
 
       private
 
-      def build_signature_element(noko, private_key, certificate, signature_method, digest_method)
-        signature_element = Nokogiri::XML::Builder.new do |xml|
+      def build_signature_node(noko, private_key, certificate, signature_method, digest_method)
+        signature_node = Nokogiri::XML::Builder.new do |xml|
           xml['ds'].Signature('xmlns:ds' => RubySaml::XML::DSIG) do
             xml['ds'].SignedInfo do
               xml['ds'].CanonicalizationMethod(Algorithm: RubySaml::XML::C14N)
@@ -77,11 +79,11 @@ def build_signature_element(noko, private_key, certificate, signature_method, di
         end.doc.root
 
         # Set the signature value
-        signed_info_element = signature_element.at_xpath('//ds:SignedInfo', 'ds' => RubySaml::XML::DSIG)
-        sig_value_element = signature_element.at_xpath('//ds:SignatureValue', 'ds' => RubySaml::XML::DSIG)
-        sig_value_element.content = signature_value(signed_info_element, private_key, signature_method)
+        signed_info_node = signature_node.at_xpath('//ds:SignedInfo', 'ds' => RubySaml::XML::DSIG)
+        signature_value_node = signature_node.at_xpath('//ds:SignatureValue', 'ds' => RubySaml::XML::DSIG)
+        signature_value_node.content = signature_value(signed_info_node, private_key, signature_method)
 
-        signature_element
+        signature_node
       end
 
       def digest_value(document, digest_method)
@@ -93,11 +95,11 @@ def digest_value(document, digest_method)
         Base64.strict_encode64(hash_algorithm.digest(canon_doc))
       end
 
-      def signature_value(signed_info_element, private_key, signature_method)
+      def signature_value(signed_info_node, private_key, signature_method)
         canon_algorithm = RubySaml::XML.canon_algorithm(RubySaml::XML::C14N)
         hash_algorithm = RubySaml::XML.hash_algorithm(signature_method).new
 
-        canon_string = signed_info_element.canonicalize(canon_algorithm)
+        canon_string = signed_info_node.canonicalize(canon_algorithm)
         Base64.strict_encode64(private_key.sign(hash_algorithm, canon_string))
       end