apricoteatsgorilla.rb in smacks-apricoteatsgorilla-0.2.0

- old
+ new

@@ -1,26 +1,45 @@
 # -*- coding: utf-8 -*-
 require 'rubygems'
 require 'hpricot'
 
-# Apricot eats Gorilla converts SOAP response messages to Ruby hashes.
-# It's based on CobraVsMongoose but uses Hpricot instead of REXML and it
-# also doesn't follow the BadgerFish convention.
+# Apricot eats Gorilla translates between XML documents and Ruby hashes.
+# It's based on CobraVsMongoose but uses Hpricot instead of REXML to parse
+# XML and it also doesn't follow the BadgerFish convention.
+# 
+# It's initial purpose was to convert SOAP response messages to Ruby hashes,
+# but it quickly evolved into a more general translation tool.
 class ApricotEatsGorilla
 
-  # Converts a given SOAP response message into a Ruby Hash.
-  def self.soap_response_to_hash(xml, root_node = nil)
-    xml = prepare_xml(xml)
-    root_node ||= "//return"
+  # Converts XML into a Ruby Hash. Starts parsing at root node by default.
+  # Call with XPath expession (Hpricot search) as second parameter to define
+  # a custom root node. The root node itself is not included in the Hash.
+  # 
+  # E.g.
+  #  xml = "<dude><likes>beer</likes><hates>appletini</hates></dude>"
+  #  ApricotEatsGorilla.xml_to_hash(xml)
+  #  # => { "hates" => "appletini", "likes" => "beer" }
+  def self.xml_to_hash(xml, root_node = nil)
+    xml = clean_xml(xml)
     doc = Hpricot.XML(xml)
-    xml_node_to_hash doc.at(root_node)
+    root = root_node ? doc.at(root_node) : doc.root
+    xml_node_to_hash(root)
   end
 
+  # Converts a Ruby Hash to XML.
+  # 
+  # E.g.
+  #  hash = { "dude" => { "likes" => "beer", "hates" => "appletini" } }
+  #  ApricotEatsGorilla.hash_to_xml(hash)
+  #  # => "<dude><hates>appletini</hates><likes>beer</likes></dude>"
+  def self.hash_to_xml(hash)
+    nested_data_to_xml(hash.keys.first, hash.values.first)
+  end
+
 private
 
-  # Converts XML nodes into a Ruby Hash. Recursively calls itself to grab
-  # nested XML nodes and values.
+  # Converts XML nodes into a Ruby Hash.
   def self.xml_node_to_hash(node)
     this_node = {}
 
     node.each_child do |child|
       if child.children.nil?
@@ -43,11 +62,46 @@
     end
 
     this_node
   end
 
+  # Converts a Ruby Hash to XML.
+  def self.nested_data_to_xml(name, item)
+    children = {}
+    case item
+    when String
+      make_tag(name) { item }
+    when Array
+      item.map { |subitem| nested_data_to_xml(name, subitem) }.join
+    when Hash
+      make_tag(name) do
+        item.map { |tag, value|
+          case value
+          when String
+            make_tag(tag) { value }
+          when Array
+            value.map { |subitem| nested_data_to_xml(tag, subitem) }.join
+          when Hash
+            nested_data_to_xml(tag, value)
+          end
+        }.join
+      end
+    end
+  end
+
+  # Helper to create an XML tag. Expects a block for tag content.
+  # Defaults to an empty element tag in case no block was supplied.
+  def self.make_tag(name)
+    body = yield
+    if body && !body.empty?
+      "<#{name}>" << body << "</#{name}>"
+    else
+      "<#{name} />"
+    end
+  end
+  
   # Helper to remove line breaks and whitespace between XML nodes.
-  def self.prepare_xml(xml)
+  def self.clean_xml(xml)
     xml = xml.gsub(/\n+/, "")
     xml = xml.gsub(/(>)\s*(<)/, '\1\2')
   end
 
   # Helper to convert "true" and "false" strings to boolean values.