Switch to the oslo_utils.fileutils

fileutils is graduated in the oslo.utils library.
Remove old implementation of the read_cached_file function
in the nova.utils and move from the fileutils the read_cached_file
and delete_cached_file functions to the nova.utils module and
the unit tests for these functions.

Implements: blueprint graduate-fileutils[1]
[1] https://blueprints.launchpad.net/oslo-incubator/+spec/graduate-fileutils

Depends-On: I51ba9076e1fbc16145ee2311f47b7768c16dcb20 (requirements)

Change-Id: I849f1c74ec811dbe82ba6270569a008a49eab465

Author: SVilgelm

nova/api/openstack/compute/contrib/cloudpipe.py

@@ -15,6 +15,7 @@
 """Connect your vlan to the world."""
 
 from oslo_config import cfg
+from oslo_utils import fileutils
 from oslo_utils import timeutils
 from webob import exc
 
@@ -26,7 +27,6 @@
 from nova import exception
 from nova.i18n import _
 from nova import network
-from nova.openstack.common import fileutils
 from nova import utils
 
 CONF = cfg.CONF

nova/api/openstack/compute/plugins/v3/cloudpipe.py

@@ -15,6 +15,7 @@
 """Connect your vlan to the world."""
 
 from oslo_config import cfg
+from oslo_utils import fileutils
 from oslo_utils import timeutils
 from webob import exc
 
@@ -30,7 +31,6 @@
 from nova.i18n import _
 from nova import network
 from nova import objects
-from nova.openstack.common import fileutils
 from nova import utils
 
 CONF = cfg.CONF

nova/cells/state.py

@@ -36,7 +36,6 @@
 from nova import exception
 from nova.i18n import _LE
 from nova import objects
-from nova.openstack.common import fileutils
 from nova import rpc
 from nova import utils
 
@@ -484,8 +483,8 @@ def _cell_data_sync(self, force=False):
         :param force: If True, cell status will be updated regardless
                       of whether it's time to do so.
         """
-        reloaded, data = fileutils.read_cached_file(self.cells_config_path,
-                                                    force_reload=force)
+        reloaded, data = utils.read_cached_file(self.cells_config_path,
+                                                force_reload=force)
 
         if reloaded:
             LOG.debug("Updating cell cache from config file.")

nova/cloudpipe/pipelib.py

@@ -26,14 +26,14 @@
 
 from oslo_config import cfg
 from oslo_log import log as logging
+from oslo_utils import fileutils
 
 from nova import compute
 from nova.compute import flavors
 from nova import crypto
 from nova import db
 from nova import exception
 from nova.i18n import _
-from nova.openstack.common import fileutils
 from nova import paths
 from nova import utils
 

nova/crypto.py

@@ -32,6 +32,7 @@
 from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_utils import excutils
+from oslo_utils import fileutils
 from oslo_utils import timeutils
 import paramiko
 from pyasn1.codec.der import encoder as der_encoder
@@ -42,7 +43,6 @@
 from nova import db
 from nova import exception
 from nova.i18n import _, _LE
-from nova.openstack.common import fileutils
 from nova import paths
 from nova import utils
 

nova/network/linux_net.py

@@ -29,14 +29,14 @@
 from oslo_log import log as logging
 from oslo_serialization import jsonutils
 from oslo_utils import excutils
+from oslo_utils import fileutils
 from oslo_utils import importutils
 from oslo_utils import timeutils
 import six
 
 from nova import exception
 from nova.i18n import _, _LE, _LW
 from nova import objects
-from nova.openstack.common import fileutils
 from nova import paths
 from nova.pci import utils as pci_utils
 from nova import utils

nova/objectstore/s3server.py

@@ -41,12 +41,12 @@
 from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_log import versionutils
+from oslo_utils import fileutils
 import routes
 import six
 import webob
 
 from nova.i18n import _LW
-from nova.openstack.common import fileutils
 from nova import paths
 from nova import utils
 from nova import wsgi

nova/openstack/common/fileutils.py

@@ -101,9 +101,8 @@
 import six.moves.urllib.parse as urlparse
 import six.moves.urllib.request as urlrequest
 
-from nova.openstack.common import fileutils
 from nova.openstack.common._i18n import _, _LE
-
+from nova import utils
 
 policy_opts = [
     cfg.StrOpt('policy_file',
@@ -248,7 +247,7 @@ def set_rules(self, rules, overwrite=True, use_conf=False):
     def clear(self):
         """Clears Enforcer rules, policy's cache and policy's path."""
         self.set_rules({})
-        fileutils.delete_cached_file(self.policy_path)
+        utils.delete_cached_file(self.policy_path)
         self.default_rule = None
         self.policy_path = None
 
@@ -287,7 +286,7 @@ def _walk_through_policy_directory(path, func, *args):
             func(os.path.join(path, policy_file), *args)
 
     def _load_policy_file(self, path, force_reload, overwrite=True):
-            reloaded, data = fileutils.read_cached_file(
+            reloaded, data = utils.read_cached_file(
                 path, force_reload=force_reload)
             if reloaded or not self.rules or not overwrite:
                 rules = Rules.load_json(data, self.default_rule)

nova/openstack/common/policy.py

@@ -28,8 +28,8 @@
 from nova.db.sqlalchemy import models
 from nova import exception
 from nova import objects
-from nova.openstack.common import fileutils
 from nova import test
+from nova import utils
 
 FAKE_COMPUTES = [
     ('host1', 1024, 100, 0, 0),
@@ -114,7 +114,7 @@ def test_cells_config_not_found(self):
         self.assertEqual(['no_such_file_exists.conf'], e.config_files)
 
     @mock.patch.object(cfg.ConfigOpts, 'find_file')
-    @mock.patch.object(fileutils, 'read_cached_file')
+    @mock.patch.object(utils, 'read_cached_file')
     def test_filemanager_returned(self, mock_read_cached_file, mock_find_file):
         mock_find_file.return_value = "/etc/nova/cells.json"
         mock_read_cached_file.return_value = (False, six.StringIO({}))

nova/tests/unit/cells/test_cells_state_manager.py

@@ -25,6 +25,7 @@
 from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_serialization import jsonutils
+from oslo_utils import fileutils
 from oslo_utils import timeutils
 
 from nova import context
@@ -33,7 +34,6 @@
 from nova.network import driver
 from nova.network import linux_net
 from nova import objects
-from nova.openstack.common import fileutils
 from nova import test
 from nova import utils
 

nova/tests/unit/network/test_linux_net.py

@@ -20,9 +20,9 @@
 import mock
 from mox3 import mox
 from oslo_config import cfg
+from oslo_utils import fileutils
 
 from nova import context
-from nova.openstack.common import fileutils
 from nova import test
 from nova.tests.unit import fake_instance
 from nova import utils