Migrate default policy file from JSON to YAML

Default value of 'CONF.oslo_policy.policy_file' config option
has been changed from 'policy.json' to 'policy.yaml'. If new default
file 'policy.yaml' does not exist but old default 'policy.json' exist
then fallback to use old default file.

An upgrade checks is added to check the policy_file format and
fail upgrade checks if it is JSON formatted.

Added a warning in policy doc about JSON formatted file is deprecated,
also removed all the reference to policy.json file in doc as well as
in tests.

Related Blueprint: policy-json-to-yaml

Closes-Bug: #1875418

Change-Id: Ic4d3b998bb9701cb1e3ef12d9bb6f4d91cc19c18

Author: gmaanos

doc/source/cli/nova-status.rst

@@ -139,6 +139,10 @@ Upgrade
   * Checks for the policy files are not automatically overwritten with
     new defaults.
 
+  **22.0.0 (Victoria)**
+
+  * Checks for the policy files is not JSON-formatted.
+
 See Also
 ========
 

doc/source/configuration/policy-concepts.rst

@@ -1,10 +1,19 @@
 Understanding Nova Policies
 ===========================
 
+.. warning::
+
+   JSON formatted policy file is deprecated since Nova 22.0.0(Victoria).
+   Use YAML formatted file. Use `oslopolicy-convert-json-to-yaml`__ tool
+   to convert the existing JSON to YAML formatted policy file in backward
+   compatible way.
+
+.. __: https://docs.openstack.org/oslo.policy/latest/cli/oslopolicy-convert-json-to-yaml.html
+
 Nova supports a rich policy system that has evolved significantly over its
 lifetime. Initially, this took the form of a large, mostly hand-written
-``policy.json`` file but, starting in the Newton (14.0.0) release, policy
-defaults have been defined in the codebase, requiring the ``policy.json``
+``policy.yaml`` file but, starting in the Newton (14.0.0) release, policy
+defaults have been defined in the codebase, requiring the ``policy.yaml``
 file only to override these defaults.
 
 In the Ussuri (21.0.0) release, further work was undertaken to address some

doc/source/configuration/policy.rst

@@ -4,6 +4,15 @@ Nova Policies
 
 The following is an overview of all available policies in Nova.
 
+.. warning::
+
+   JSON formatted policy file is deprecated since Nova 22.0.0(Victoria).
+   Use YAML formatted file. Use `oslopolicy-convert-json-to-yaml`__ tool
+   to convert the existing JSON to YAML formatted policy file in backward
+   compatible way.
+
+.. __: https://docs.openstack.org/oslo.policy/latest/cli/oslopolicy-convert-json-to-yaml.html
+
 .. only:: html
 
    For a sample configuration file, refer to :doc:`sample-policy`.

doc/source/install/verify.rst

@@ -127,3 +127,7 @@ Verify operation of the Compute service.
       | Result: Success                                                    |
       | Details: None                                                      |
       +--------------------------------------------------------------------+
+      | Check: Policy File JSON to YAML Migration                          |
+      | Result: Success                                                    |
+      | Details: None                                                      |
+      +--------------------------------------------------------------------+

lower-constraints.txt

@@ -69,21 +69,21 @@ os-xenapi==0.3.4
 osc-lib==1.10.0
 oslo.cache==1.26.0
 oslo.concurrency==3.29.0
-oslo.config==6.1.0
+oslo.config==6.8.0
 oslo.context==2.22.0
 oslo.db==4.44.0
 oslo.i18n==3.15.3
 oslo.log==3.36.0
 oslo.messaging==10.3.0
 oslo.middleware==3.31.0
-oslo.policy==3.1.0
+oslo.policy==3.4.0
 oslo.privsep==1.33.2
 oslo.reports==1.18.0
 oslo.rootwrap==5.8.0
 oslo.serialization==2.21.1
 oslo.service==1.40.1
 oslo.upgradecheck==0.1.1
-oslo.utils==4.1.0
+oslo.utils==4.5.0
 oslo.versionedobjects==1.35.0
 oslo.vmware==2.17.0
 oslotest==3.8.0
@@ -127,11 +127,11 @@ python-subunit==1.4.0
 pytz==2018.3
 PyYAML==3.13
 repoze.lru==0.7
-requests==2.14.2
+requests==2.23.0
 requests-mock==1.2.0
 requestsexceptions==1.4.0
 retrying==1.3.3
-rfc3986==1.1.0
+rfc3986==1.2.0
 Routes==2.3.1
 simplejson==3.13.2
 six==1.11.0

nova/cmd/status.py

@@ -25,6 +25,7 @@
 from oslo_config import cfg
 from oslo_serialization import jsonutils
 from oslo_upgradecheck import upgradecheck
+from oslo_utils import fileutils
 import pkg_resources
 import six
 from sqlalchemy import func as sqlfunc
@@ -409,6 +410,23 @@ def _check_policy(self):
         policy.reset()
         return status
 
+    def _check_policy_json(self):
+        "Checks to see if policy file is JSON-formatted policy file."
+        msg = _("Your policy file  is JSON-formatted which is "
+                "deprecated since Victoria release (Nova 22.0.0). "
+                "You need to switch to YAML-formatted file. You can use the "
+                "``oslopolicy-convert-json-to-yaml`` tool to convert existing "
+                "JSON-formatted files to YAML-formatted files in a "
+                "backwards-compatible manner: "
+                "https://docs.openstack.org/oslo.policy/"
+                "latest/cli/oslopolicy-convert-json-to-yaml.html.")
+        status = upgradecheck.Result(upgradecheck.Code.SUCCESS)
+        # Check if policy file exist and is JSON-formatted.
+        policy_path = CONF.find_file(CONF.oslo_policy.policy_file)
+        if policy_path and fileutils.is_json(policy_path):
+            status = upgradecheck.Result(upgradecheck.Code.FAILURE, msg)
+        return status
+
     # The format of the check functions is to return an upgradecheck.Result
     # object with the appropriate upgradecheck.Code and details set. If the
     # check hits warnings or failures then those should be stored in the
@@ -427,6 +445,8 @@ def _check_policy(self):
         (_('Cinder API'), _check_cinder),
         # Added in Ussuri
         (_('Policy Scope-based Defaults'), _check_policy),
+        # Added in Victoria
+        (_('Policy File JSON to YAML Migration'), _check_policy_json),
     )
 
 

nova/policy.py

@@ -19,6 +19,7 @@
 
 from oslo_config import cfg
 from oslo_log import log as logging
+from oslo_policy import opts
 from oslo_policy import policy
 from oslo_utils import excutils
 
@@ -40,6 +41,35 @@
 saved_file_rules = []
 KEY_EXPR = re.compile(r'%\((\w+)\)s')
 
+# TODO(gmann): Remove setting the default value of config policy_file
+# once oslo_policy change the default value to 'policy.yaml'.
+# https://github.com/openstack/oslo.policy/blob/a626ad12fe5a3abd49d70e3e5b95589d279ab578/oslo_policy/opts.py#L49
+DEFAULT_POLICY_FILE = 'policy.yaml'
+opts.set_defaults(cfg.CONF, DEFAULT_POLICY_FILE)
+
+
+def pick_policy_file(policy_file):
+    # TODO(gmann): We have changed the default value of
+    # CONF.oslo_policy.policy_file option to 'policy.yaml' in Victoria
+    # release. To avoid breaking any deployment relying on default
+    # value, we need to add this is fallback logic to pick the old default
+    # policy file (policy.json) if exist. We can to remove this fallback
+    # logic sometime in future.
+    if policy_file:
+        return policy_file
+
+    if CONF.oslo_policy.policy_file == DEFAULT_POLICY_FILE:
+        location = CONF.get_location('policy_file', 'oslo_policy').location
+        if CONF.find_file(CONF.oslo_policy.policy_file):
+            return CONF.oslo_policy.policy_file
+        elif location in [cfg.Locations.opt_default,
+                          cfg.Locations.set_default]:
+            old_default = 'policy.json'
+            if CONF.find_file(old_default):
+                return old_default
+    # Return overridden value
+    return CONF.oslo_policy.policy_file
+
 
 def reset():
     global _ENFORCER
@@ -67,11 +97,12 @@ def init(policy_file=None, rules=None, default_rule=None, use_conf=True,
     global saved_file_rules
 
     if not _ENFORCER:
-        _ENFORCER = policy.Enforcer(CONF,
-                                    policy_file=policy_file,
-                                    rules=rules,
-                                    default_rule=default_rule,
-                                    use_conf=use_conf)
+        _ENFORCER = policy.Enforcer(
+            CONF,
+            policy_file=pick_policy_file(policy_file),
+            rules=rules,
+            default_rule=default_rule,
+            use_conf=use_conf)
         # NOTE(gmann): Explictly disable the warnings for policies
         # changing their default check_str. During policy-defaults-refresh
         # work, all the policy defaults have been changed and warning for

nova/tests/unit/cmd/test_status.py

@@ -22,11 +22,16 @@
 
 import fixtures
 import mock
+import os
 from six.moves import StringIO
+import tempfile
+import yaml
 
 from keystoneauth1 import exceptions as ks_exc
 from keystoneauth1 import loading as keystone
 from keystoneauth1 import session
+from oslo_config import cfg
+from oslo_serialization import jsonutils
 from oslo_upgradecheck import upgradecheck
 from oslo_utils.fixture import uuidsentinel as uuids
 from oslo_utils import uuidutils
@@ -602,3 +607,63 @@ class TestUpgradeCheckPolicyEnableScope(TestUpgradeCheckPolicy):
     def setUp(self):
         super(TestUpgradeCheckPolicyEnableScope, self).setUp()
         self.flags(enforce_scope=True, group="oslo_policy")
+
+
+class TestUpgradeCheckPolicyJSON(test.NoDBTestCase):
+
+    def setUp(self):
+        super(TestUpgradeCheckPolicyJSON, self).setUp()
+        self.cmd = status.UpgradeCommands()
+        policy.CONF.clear_override('policy_file', group='oslo_policy')
+        self.data = {
+            'rule_admin': 'True',
+            'rule_admin2': 'is_admin:True'
+        }
+        self.temp_dir = self.useFixture(fixtures.TempDir())
+        fd, self.json_file = tempfile.mkstemp(dir=self.temp_dir.path)
+        fd, self.yaml_file = tempfile.mkstemp(dir=self.temp_dir.path)
+
+        with open(self.json_file, 'w') as fh:
+            jsonutils.dump(self.data, fh)
+        with open(self.yaml_file, 'w') as fh:
+            yaml.dump(self.data, fh)
+
+        original_search_dirs = cfg._search_dirs
+
+        def fake_search_dirs(dirs, name):
+            dirs.append(self.temp_dir.path)
+            return original_search_dirs(dirs, name)
+
+        self.stub_out('oslo_config.cfg._search_dirs', fake_search_dirs)
+
+    def test_policy_json_file_fail_upgrade(self):
+        # Test with policy json file full path set in config.
+        self.flags(policy_file=self.json_file, group="oslo_policy")
+        self.assertEqual(upgradecheck.Code.FAILURE,
+                         self.cmd._check_policy_json().code)
+
+    def test_policy_yaml_file_pass_upgrade(self):
+        # Test with full policy yaml file path set in config.
+        self.flags(policy_file=self.yaml_file, group="oslo_policy")
+        self.assertEqual(upgradecheck.Code.SUCCESS,
+                         self.cmd._check_policy_json().code)
+
+    def test_no_policy_file_pass_upgrade(self):
+        # Test with no policy file exist.
+        self.assertEqual(upgradecheck.Code.SUCCESS,
+                         self.cmd._check_policy_json().code)
+
+    def test_default_policy_yaml_file_pass_upgrade(self):
+        tmpfilename = os.path.join(self.temp_dir.path, 'policy.yaml')
+        with open(tmpfilename, 'w') as fh:
+            yaml.dump(self.data, fh)
+        self.assertEqual(upgradecheck.Code.SUCCESS,
+                         self.cmd._check_policy_json().code)
+
+    def test_old_default_policy_json_file_fail_upgrade(self):
+        self.flags(policy_file='policy.json', group="oslo_policy")
+        tmpfilename = os.path.join(self.temp_dir.path, 'policy.json')
+        with open(tmpfilename, 'w') as fh:
+            jsonutils.dump(self.data, fh)
+        self.assertEqual(upgradecheck.Code.FAILURE,
+                         self.cmd._check_policy_json().code)

nova/tests/unit/test_policy.py

@@ -17,10 +17,13 @@
 
 import os.path
 
+import fixtures
 import mock
+from oslo_config import cfg
 from oslo_policy import policy as oslo_policy
 from oslo_serialization import jsonutils
 import requests_mock
+import yaml
 
 from nova import context
 from nova import exception
@@ -572,3 +575,70 @@ def test_rule_missing(self):
             self.system_reader_or_owner_rules +
             self.allow_nobody_rules + special_rules)
         self.assertEqual(set([]), result)
+
+
+class PickPolicyFileTestCase(test.NoDBTestCase):
+
+    def setUp(self):
+        super(PickPolicyFileTestCase, self).setUp()
+        self.data = {
+            'rule_admin': 'True',
+            'rule_admin2': 'is_admin:True'
+        }
+        policy.CONF.clear_override('policy_file', group='oslo_policy')
+        self.tmpdir = self.useFixture(fixtures.TempDir())
+        original_search_dirs = cfg._search_dirs
+
+        def fake_search_dirs(dirs, name):
+            dirs.append(self.tmpdir.path)
+            return original_search_dirs(dirs, name)
+
+        self.stub_out('oslo_config.cfg._search_dirs', fake_search_dirs)
+
+    def test_non_config_policy_file(self):
+        tmpfilename = 'nova-policy.yaml'
+        self.flags(policy_file=tmpfilename, group='oslo_policy')
+        selected_policy_file = policy.pick_policy_file(
+            policy_file='non-config-file')
+        self.assertEqual(policy.CONF.oslo_policy.policy_file, tmpfilename)
+        self.assertEqual(selected_policy_file, 'non-config-file')
+
+    def test_overridden_policy_file(self):
+        tmpfilename = 'nova-policy.yaml'
+        self.flags(policy_file=tmpfilename, group='oslo_policy')
+        selected_policy_file = policy.pick_policy_file(policy_file=None)
+        self.assertEqual(policy.CONF.oslo_policy.policy_file, tmpfilename)
+        self.assertEqual(selected_policy_file, tmpfilename)
+
+    def test_only_new_default_policy_file_exist(self):
+        tmpfilename = os.path.join(self.tmpdir.path, 'policy.yaml')
+        with open(tmpfilename, 'w') as fh:
+            yaml.dump(self.data, fh)
+
+        selected_policy_file = policy.pick_policy_file(policy_file=None)
+        self.assertEqual(policy.CONF.oslo_policy.policy_file, 'policy.yaml')
+        self.assertEqual(selected_policy_file, 'policy.yaml')
+
+    @mock.patch.object(policy.CONF, 'get_location')
+    def test_only_old_default_policy_file_exist(self, mock_get):
+        mock_get.return_value = cfg.LocationInfo(cfg.Locations.set_default,
+                                                 'None')
+        tmpfilename = os.path.join(self.tmpdir.path, 'policy.json')
+        with open(tmpfilename, 'w') as fh:
+            jsonutils.dump(self.data, fh)
+
+        selected_policy_file = policy.pick_policy_file(policy_file=None)
+        self.assertEqual(policy.CONF.oslo_policy.policy_file, 'policy.yaml')
+        self.assertEqual(selected_policy_file, 'policy.json')
+
+    def test_both_default_policy_file_exist(self):
+        tmpfilename1 = os.path.join(self.tmpdir.path, 'policy.json')
+        with open(tmpfilename1, 'w') as fh:
+            jsonutils.dump(self.data, fh)
+        tmpfilename2 = os.path.join(self.tmpdir.path, 'policy.yaml')
+        with open(tmpfilename2, 'w') as fh:
+            yaml.dump(self.data, fh)
+
+        selected_policy_file = policy.pick_policy_file(policy_file=None)
+        self.assertEqual(policy.CONF.oslo_policy.policy_file, 'policy.yaml')
+        self.assertEqual(selected_policy_file, 'policy.yaml')

releasenotes/notes/bug-1875418-default-policy-file-change-22bd4cc6e27e0091.yaml

@@ -0,0 +1,19 @@
+---
+upgrade:
+  - |
+    The default value of ``[oslo_policy] policy_file`` config option has been
+    changed from ``policy.json``
+    to ``policy.yaml``. Nova policy new defaults since 21.0.0 and current
+    default value of ``[oslo_policy] policy_file`` config option (``policy.json``)
+    does not work when ``policy.json`` is generated by
+    `oslopolicy-sample-generator <https://docs.openstack.org/oslo.policy/latest/cli/oslopolicy-sample-generator.html>`_  tool.
+    Refer to `bug 1875418 <https://bugs.launchpad.net/nova/+bug/1875418>`_
+    for more details.
+    Also check `oslopolicy-convert-json-to-yaml <https://docs.openstack.org/oslo.policy/latest/cli/oslopolicy-convert-json-to-yaml.html>`_
+    tool to convert the JSON to YAML formatted policy file in
+    backward compatible way.
+fixes:
+  - |
+    Bug `1875418 <https://bugs.launchpad.net/nova/+bug/1875418>`_ is fixed
+    by changing the default value of ``[oslo_policy] policy_file`` config
+    option to YAML format.