Move introspection parser to OpenBMCMapper

Doing this so rest-dbus can use it.
diff --git a/OpenBMCMapper.py b/OpenBMCMapper.py
index 1862a46..30a93fb 100644
--- a/OpenBMCMapper.py
+++ b/OpenBMCMapper.py
@@ -16,6 +16,9 @@
 # implied. See the License for the specific language governing
 # permissions and limitations under the License.
 
+from xml.etree import ElementTree
+import dbus
+
 MAPPER_NAME = 'org.openbmc.objectmapper'
 MAPPER_IFACE = MAPPER_NAME + '.ObjectMapper'
 MAPPER_PATH = '/org/openbmc/objectmapper/objectmapper'
@@ -41,3 +44,107 @@
 		if not last:
 			last = self.depth()
 		return prefix + '/'.join(self.parts[first:last])
+
+class IntrospectionNodeParser:
+	def __init__(self, data):
+		self.data = data
+		self.cache = {}
+
+	def parse_args(self):
+		return [ x.attrib for x in self.data.findall('arg') ]
+
+	def parse_children(self):
+		return [ x.attrib['name'] for x in self.data.findall('node') ]
+
+	def parse_method_or_signal(self):
+		name = self.data.attrib['name']
+		return name, self.parse_args()
+
+	def parse_interface(self):
+		iface = {}
+		iface['method'] = {}
+		iface['signal'] = {}
+		name = self.data.attrib['name']
+
+		for node in self.data:
+			p = IntrospectionNodeParser(node)
+			if node.tag not in ['method', 'signal']:
+				continue
+			n, element = p.parse_method_or_signal()
+			iface[node.tag][n] = element
+
+		return name, iface
+
+	def parse_node(self):
+		if self.cache:
+			return self.cache
+
+		self.cache['interfaces'] = {}
+		self.cache['children'] = []
+
+		for node in self.data:
+			p = IntrospectionNodeParser(node)
+			if node.tag == 'interface':
+				name, ifaces = p.parse_interface()
+				self.cache['interfaces'][name] = ifaces
+			elif node.tag == 'node':
+				self.cache['children'] = self.parse_children()
+
+		return self.cache
+
+	def get_interfaces(self):
+		return self.parse_node()['interfaces']
+
+	def get_children(self):
+		return self.parse_node()['children']
+
+	def recursive_binding(self):
+		return any('/' in s for s in self.get_children())
+
+class IntrospectionParser:
+	def __init__(self, name, bus):
+		self.name = name
+		self.bus = bus
+
+	def _introspect(self, path):
+		try:
+			obj = self.bus.get_object(self.name, path)
+			iface = dbus.Interface(obj, dbus.BUS_DAEMON_IFACE + '.Introspectable')
+			data = iface.Introspect()
+		except dbus.DBusException:
+			return None
+
+		return IntrospectionNodeParser(ElementTree.fromstring(data))
+
+	def _discover_flat(self, path, parser):
+		items = {}
+		interfaces = parser.get_interfaces().keys()
+		if interfaces:
+			items[path] = {}
+			items[path]['interfaces'] = interfaces
+
+		return items
+
+	def introspect(self, path = '/', parser = None):
+		items = {}
+		if not parser:
+			parser = self._introspect(path)
+		if not parser:
+			return {}
+		items.update(self._discover_flat(path, parser))
+
+		if path != '/':
+			path += '/'
+
+		if parser.recursive_binding():
+			callback = self._discover_flat
+		else:
+			callback = self.introspect
+
+		for k in parser.get_children():
+			parser = self._introspect(path + k)
+			if not parser:
+				continue
+			items.update(callback(path + k, parser))
+
+		return items