[2252] rename the helper method name

rename "get_ipver_str()" to "_get_ipver_str()" to protect an access
from outside. This is for addressing the reviewer's comment.

src/bin/xfrin/tests/xfrin_test.py

@@ -1072,11 +1072,11 @@ class TestAXFR(TestXfrinConnection):
         class FakeSocket(): pass
         self.conn.socket = FakeSocket()
         self.conn.socket.family = socket.AF_INET
-        self.assertEqual(self.conn.get_ipver_str(), 'v4')
+        self.assertEqual(self.conn._get_ipver_str(), 'v4')
         self.conn.socket.family = socket.AF_INET6
-        self.assertEqual(self.conn.get_ipver_str(), 'v6')
+        self.assertEqual(self.conn._get_ipver_str(), 'v6')
         self.conn.socket.family = None
-        self.assertIsNone(self.conn.get_ipver_str())
+        self.assertIsNone(self.conn._get_ipver_str())
         self.conn.socket = orig_socket
 
     def test_soacheck(self):

src/bin/xfrin/xfrin.py.in

@@ -893,7 +893,7 @@ class XfrinConnection(asyncore.dispatcher):
         # All okay, return it
         return soa
 
-    def get_ipver_str(self):
+    def _get_ipver_str(self):
         """Returns a 'v4' or 'v6' string representing a IP version
         depending on the socket family"""
         if self.socket.family == socket.AF_INET:
@@ -913,7 +913,7 @@ class XfrinConnection(asyncore.dispatcher):
         self._send_query(RRType.SOA)
         # count soaoutv4 or soaoutv6 requests
         self._counters.inc('zones', self._zone_name.to_text(),
-                           'soaout' + self.get_ipver_str())
+                           'soaout' + self._get_ipver_str())
         data_len = self._get_request_response(2)
         msg_len = socket.htons(struct.unpack('H', data_len)[0])
         soa_response = self._get_request_response(msg_len)
@@ -961,7 +961,7 @@ class XfrinConnection(asyncore.dispatcher):
             # count (A|X)IXFR requests for statistics
             self._counters.inc('zones', self._zone_name.to_text(),
                                req_str.lower() + 'req' +
-                               self.get_ipver_str())
+                               self._get_ipver_str())
             self.__state = XfrinInitialSOA()
             self._handle_xfrin_responses()
             # Depending what data was found, we log different status reports