Port swift.common.utils.StatsdClient to Python 3

* StatsdClient._send(): on Python 3, encode parts to UTF-8 and
  replace '|' with b'|' to join parts.
* timing_stats(): replace func.func_name with func.__name__. The
  func_name attribute of functions was removed on Python 3, whereas
  the __name__ attribute is available on Python 2 and Python 3.
* Fix unit tests to use bytes

Change-Id: Ic279c9b54e91aabcc52587eed7758e268ffb155e

swift/common/utils.py

@@ -1166,11 +1166,13 @@ class StatsdClient(object):
                 parts.append('@%s' % (sample_rate,))
             else:
                 return
+        if six.PY3:
+            parts = [part.encode('utf-8') for part in parts]
         # Ideally, we'd cache a sending socket in self, but that
         # results in a socket getting shared by multiple green threads.
         with closing(self._open_socket()) as sock:
             try:
-                return sock.sendto('|'.join(parts), self._target)
+                return sock.sendto(b'|'.join(parts), self._target)
             except IOError as err:
                 if self.logger:
                     self.logger.warn(
@@ -1227,7 +1229,7 @@ def timing_stats(**dec_kwargs):
     swift's wsgi server controllers, based on response code.
     """
     def decorating_func(func):
-        method = func.func_name
+        method = func.__name__
 
         @functools.wraps(func)
         def _timing_stats(ctrl, *args, **kwargs):

test/unit/common/test_utils.py

@@ -34,6 +34,7 @@ import sys
 import json
 import math
 
+import six
 from six import BytesIO, StringIO
 from six.moves.queue import Queue, Empty
 from six.moves import range
@@ -3650,7 +3651,7 @@ class TestStatsdLogging(unittest.TestCase):
         self.assertEqual(len(mock_socket.sent), 1)
 
         payload = mock_socket.sent[0][0]
-        self.assertTrue(payload.endswith("|@0.5"))
+        self.assertTrue(payload.endswith(b"|@0.5"))
 
     def test_sample_rates_with_sample_rate_factor(self):
         logger = utils.get_logger({
@@ -3676,8 +3677,10 @@ class TestStatsdLogging(unittest.TestCase):
         self.assertEqual(len(mock_socket.sent), 1)
 
         payload = mock_socket.sent[0][0]
-        self.assertTrue(payload.endswith("|@%s" % effective_sample_rate),
-                        payload)
+        suffix = "|@%s" % effective_sample_rate
+        if six.PY3:
+            suffix = suffix.encode('utf-8')
+        self.assertTrue(payload.endswith(suffix), payload)
 
         effective_sample_rate = 0.587 * 0.91
         statsd_client.random = lambda: effective_sample_rate - 0.001
@@ -3685,8 +3688,10 @@ class TestStatsdLogging(unittest.TestCase):
         self.assertEqual(len(mock_socket.sent), 2)
 
         payload = mock_socket.sent[1][0]
-        self.assertTrue(payload.endswith("|@%s" % effective_sample_rate),
-                        payload)
+        suffix = "|@%s" % effective_sample_rate
+        if six.PY3:
+            suffix = suffix.encode('utf-8')
+        self.assertTrue(payload.endswith(suffix), payload)
 
     def test_timing_stats(self):
         class MockController(object):
@@ -3983,7 +3988,7 @@ class TestStatsdLoggingDelegation(unittest.TestCase):
         while True:
             try:
                 payload = self.sock.recv(4096)
-                if payload and 'STOP' in payload:
+                if payload and b'STOP' in payload:
                     return 42
                 self.queue.put(payload)
             except Exception as e:
@@ -4006,10 +4011,14 @@ class TestStatsdLoggingDelegation(unittest.TestCase):
 
     def assertStat(self, expected, sender_fn, *args, **kwargs):
         got = self._send_and_get(sender_fn, *args, **kwargs)
+        if six.PY3:
+            got = got.decode('utf-8')
         return self.assertEqual(expected, got)
 
     def assertStatMatches(self, expected_regexp, sender_fn, *args, **kwargs):
         got = self._send_and_get(sender_fn, *args, **kwargs)
+        if six.PY3:
+            got = got.decode('utf-8')
         return self.assertTrue(re.search(expected_regexp, got),
                                [got, expected_regexp])
 
@@ -4178,7 +4187,7 @@ class TestStatsdLoggingDelegation(unittest.TestCase):
                          utils.get_valid_utf8_str(valid_utf8_str))
         self.assertEqual(valid_utf8_str,
                          utils.get_valid_utf8_str(unicode_sample))
-        self.assertEqual('\xef\xbf\xbd\xef\xbf\xbd\xec\xbc\x9d\xef\xbf\xbd',
+        self.assertEqual(b'\xef\xbf\xbd\xef\xbf\xbd\xec\xbc\x9d\xef\xbf\xbd',
                          utils.get_valid_utf8_str(invalid_utf8_str))
 
     @reset_logger_state