Fix compatibility with python 3.4&3.5 (#1248)

Close https://github.com/zalando/patroni/issues/1247

patroni/ctl.py

@@ -1180,7 +1180,7 @@ def version(obj, cluster_name, member_names):
             if not member_names or m.name in member_names:
                 try:
                     response = request_patroni(m)
-                    data = json.loads(response.data)
+                    data = json.loads(response.data.decode('utf-8'))
                     version = data.get('patroni', {}).get('version')
                     pg_version = data.get('server_version')
                     pg_version_str = " PostgreSQL {0}".format(format_pg_version(pg_version)) if pg_version else ""

patroni/ha.py

@@ -553,8 +553,9 @@ class Ha(object):
 
         try:
             response = self.patroni.request(member, timeout=2, retries=0)
-            logger.info('Got response from %s %s: %s', member.name, member.api_url, response.data.decode('utf-8'))
-            return _MemberStatus.from_api_response(member, json.loads(response.data))
+            data = response.data.decode('utf-8')
+            logger.info('Got response from %s %s: %s', member.name, member.api_url, data)
+            return _MemberStatus.from_api_response(member, json.loads(data))
         except Exception as e:
             logger.warning("Request failed to %s: GET %s (%s)", member.name, member.api_url, e)
         return _MemberStatus.unknown(member)

tests/test_ctl.py

@@ -559,7 +559,7 @@ class TestCtl(unittest.TestCase):
         with patch.object(PoolManager, 'request') as mocked:
             result = self.runner.invoke(ctl, ['version'])
             assert 'patronictl version' in result.output
-            mocked.return_value.data = json.dumps({'patroni': {'version': '1.2.3'}, 'server_version': 100001})
+            mocked.return_value.data = b'{"patroni":{"version":"1.2.3"},"server_version": 100001}'
             result = self.runner.invoke(ctl, ['version', 'dummy'])
             assert '1.2.3' in result.output
         with patch.object(PoolManager, 'request', Mock(side_effect=Exception)):