kedifa: Use six for py2/py3 compatibility

kedifa/app.py

@@ -33,10 +33,7 @@ import signal
 import sqlite3
 import ssl
 import string
-try:
-  import urlparse
-except ImportError:
-  from urllib.parse import urlparse
+from six.moves.urllib import parse as urlparse
 import logging
 import logging.handlers
 

kedifa/cli.py

@@ -20,10 +20,7 @@
 from __future__ import print_function
 
 import argparse
-try:
-  import httplib
-except ImportError:
-  from http import client as httplib
+from six.moves import http_client as httplib
 import requests
 import sys
 

kedifa/test.py

@@ -17,16 +17,10 @@
 # See COPYING file for full licensing terms.
 # See https://www.nexedi.com/licensing for rationale and options.
 
-try:
-  import StringIO
-except ImportError:
-  from io import StringIO
+from six import StringIO
 import contextlib
 import datetime
-try:
-  import httplib
-except ImportError:
-  from http import client as httplib
+from six.moves import http_client as httplib
 import ipaddress
 import json
 import mock
@@ -68,7 +62,7 @@ def findFreeTCPPort(ip=''):
 
 @contextlib.contextmanager
 def captured_output():
-  new_out, new_err = StringIO.StringIO(), StringIO.StringIO()
+  new_out, new_err = StringIO(), StringIO()
   old_out, old_err = sys.stdout, sys.stderr
   try:
     sys.stdout, sys.stderr = new_out, new_err

kedifa/updater.py

 from __future__ import print_function
 
-try:
-  import httplib
-except ImportError:
-  from http import client as httplib
+from six.moves import http_client as httplib
 import json
 import os
 import requests

setup.py

@@ -55,6 +55,7 @@ setup(
     'requests',  # for getter and updater
     'zc.lockfile',  # for stateful updater
     'urllib3 >= 1.18',  # https://github.com/urllib3/urllib3/issues/258
+    'six',  # for python 2 and 3 compatibility
     'caucase',  # provides utils for certificate management;
                 # version requirement caucase >= 0.9.3 is dropped, as it
                 # is not working in some cases, but fortunately KeDiFa is