Fix version unit test on Python 3

With this change, "tox -e py34" now pass.

Changes:

* Replace unichr() with six.unichr()
* Replace StringIO.StringIO() with six.Bytes() in
  nova.crypto.generate_key_pair()
* On Python 3, replace UserDict.IterableUserDict with
  collections.UserDict
* Replace __builtin__.open with six.moves.builtins.open
* Replace ConfigParser import with six.moves.configparser
* On Python 3, get the original "queue" module instead of the "Queue"
  module in nova/virt/libvirt/host.py
* Replace urllib2 with six.moves.urllib
* tox.ini: "tox -e py34" now only runs nova.tests.unit.test_versions

Blueprint nova-python3
Change-Id: I056769c7c5b32276894f7aade8c0a27af81c42ae

nova/api/validation/parameter_types.py

@@ -19,6 +19,8 @@ import copy
 import re
 import unicodedata
 
+import six
+
 
 def _is_printable(char):
     """determine if a unicode code point is printable.
@@ -36,7 +38,7 @@ def _is_printable(char):
 
 def _get_all_chars():
     for i in range(0xFFFF):
-        yield unichr(i)
+        yield six.unichr(i)
 
 # build a regex that matches all printable characters. This allows
 # spaces in the middle of the name. Also note that the regexp below

nova/crypto.py

@@ -27,7 +27,6 @@ import binascii
 import os
 import re
 import string
-import StringIO
 import struct
 
 from oslo_concurrency import processutils
@@ -38,6 +37,7 @@ from oslo_utils import timeutils
 import paramiko
 from pyasn1.codec.der import encoder as der_encoder
 from pyasn1.type import univ
+import six
 
 from nova import context
 from nova import db
@@ -166,7 +166,7 @@ def generate_x509_fingerprint(pem_key):
 
 def generate_key_pair(bits=2048):
     key = paramiko.RSAKey.generate(bits)
-    keyout = StringIO.StringIO()
+    keyout = six.BytesIO()
     key.write_private_key(keyout)
     private_key = keyout.getvalue()
     public_key = '%s %s Generated-by-Nova' % (key.get_name(), key.get_base64())

nova/scheduler/host_manager.py

@@ -19,7 +19,11 @@ Manage hosts in the current zone.
 
 import collections
 import time
-import UserDict
+try:
+    from collections import UserDict as IterableUserDict   # Python 3
+except ImportError:
+    from UserDict import IterableUserDict                  # Python 2
+
 
 import iso8601
 from oslo_config import cfg
@@ -76,7 +80,7 @@ LOG = logging.getLogger(__name__)
 HOST_INSTANCE_SEMAPHORE = "host_instance"
 
 
-class ReadOnlyDict(UserDict.IterableUserDict):
+class ReadOnlyDict(IterableUserDict):
     """A read-only dict."""
     def __init__(self, source=None):
         self.data = {}

nova/tests/unit/test_versions.py

@@ -12,10 +12,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import __builtin__
-import StringIO
-
 from oslo_config import cfg
+import six
+from six.moves import builtins
 
 from nova import test
 from nova import version
@@ -35,7 +34,7 @@ class VersionTestCase(test.NoDBTestCase):
 
     def test_release_file(self):
         version.loaded = False
-        real_open = __builtin__.open
+        real_open = builtins.open
         real_find_file = cfg.CONF.find_file
 
         def fake_find_file(self, name):
@@ -49,11 +48,11 @@ class VersionTestCase(test.NoDBTestCase):
 vendor = ACME Corporation
 product = ACME Nova
 package = 1337"""
-                return StringIO.StringIO(data)
+                return six.StringIO(data)
 
             return real_open(path, *args, **kwargs)
 
-        self.stubs.Set(__builtin__, 'open', fake_open)
+        self.stubs.Set(builtins, 'open', fake_open)
         self.stubs.Set(cfg.ConfigOpts, 'find_file', fake_find_file)
 
         self.assertEqual(version.vendor_string(), "ACME Corporation")

nova/version.py

@@ -29,7 +29,7 @@ def _load_config():
     # Don't load in global context, since we can't assume
     # these modules are accessible when distutils uses
     # this module
-    import ConfigParser
+    from six.moves import configparser
 
     from oslo_config import cfg
 
@@ -46,7 +46,7 @@ def _load_config():
         return
 
     try:
-        cfg = ConfigParser.RawConfigParser()
+        cfg = configparser.RawConfigParser()
         cfg.read(cfgfile)
 
         if cfg.has_option("Nova", "vendor"):

nova/virt/libvirt/host.py

@@ -43,6 +43,7 @@ from oslo_log import log as logging
 from oslo_utils import excutils
 from oslo_utils import importutils
 from oslo_utils import units
+import six
 
 from nova import context as nova_context
 from nova import exception
@@ -62,7 +63,7 @@ LOG = logging.getLogger(__name__)
 
 native_socket = patcher.original('socket')
 native_threading = patcher.original("threading")
-native_Queue = patcher.original("Queue")
+native_Queue = patcher.original("queue" if six.PY3 else "Queue")
 
 CONF = cfg.CONF
 CONF.import_opt('host', 'nova.netconf')

nova/virt/libvirt/volume.py

@@ -22,13 +22,13 @@ import os
 import platform
 import re
 import time
-import urllib2
 
 from oslo_concurrency import processutils
 from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_utils import strutils
 import six
+from six.moves import urllib
 import six.moves.urllib.parse as urlparse
 
 from nova.compute import arch
@@ -1468,8 +1468,8 @@ class LibvirtScalityVolumeDriver(LibvirtBaseVolumeDriver):
             # turn local path into URL
             config = 'file://%s' % config
         try:
-            urllib2.urlopen(config, timeout=5).close()
-        except urllib2.URLError as e:
+            urllib.request.urlopen(config, timeout=5).close()
+        except urllib.error.URLError as e:
             msg = _LW("Cannot access 'scality_sofs_config': %s") % e
             LOG.warn(msg)
             raise exception.NovaException(msg)

tox.ini

@@ -40,6 +40,9 @@ setenv =
     OS_TEST_DBAPI_ADMIN_CONNECTION=mysql+pymysql://openstack_citest:openstack_citest@localhost/;postgresql://openstack_citest:openstack_citest@localhost/postgres;sqlite://
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements-py3.txt
+commands =
+  find . -type f -name "*.pyc" -delete
+  python -m testtools.run nova.tests.unit.test_versions
 
 [testenv:functional]
 usedevelop = True