[OVN] Check if OVN NB supports "Port_Group"

Added a check for OVN NB schema, looking for "Port_Group" table
(added in OVN NB schema 5.11).

This patch removes the code to support OVN without "Port_Group"
table. It is assumed that this table is always present.

Closes-Bug: #1946023

Change-Id: If193ff5bc6e1421f4fa9db3779872a82a36c8b69

neutron/cmd/sanity/checks.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import distutils
+import enum
 import re
 import shutil
 import tempfile
@@ -49,6 +50,35 @@ DNSMASQ_VERSION_HOST_ADDR6_LIST = '2.81'
 DIRECT_PORT_QOS_MIN_OVS_VERSION = '2.11'
 MINIMUM_DIBBLER_VERSION = '1.0.1'
 CONNTRACK_GRE_MODULE = 'nf_conntrack_proto_gre'
+OVN_NB_DB_SCHEMA_PORT_GROUP = '5.11'
+
+
+class OVNCheckType(enum.Enum):
+    nb_version = 0
+    nb_db_schema = 1
+    sb_version = 2
+    sb_db_schema = 3
+
+
+def _get_ovn_version(check_type):
+    if check_type in (OVNCheckType.nb_version, OVNCheckType.nb_db_schema):
+        cmd = ['ovn-nbctl', '--version']
+    elif check_type in (OVNCheckType.nb_version, OVNCheckType.nb_db_schema):
+        cmd = ['ovn-sbctl', '--version']
+    else:
+        raise RuntimeError
+
+    out = agent_utils.execute(cmd)
+    if check_type == OVNCheckType.nb_version:
+        matched_line = re.search(r"ovn-nbctl.*", out)
+    elif check_type == OVNCheckType.sb_version:
+        matched_line = re.search(r"ovn-sbctl.*", out)
+    else:
+        matched_line = re.search(r"DB Schema.*", out)
+
+    matched_version = re.search(r"(\d+\.\d+)", matched_line.group(0))
+    return versionutils.convert_version_to_tuple(matched_version.group(1) if
+                                                 matched_version else '0.0')
 
 
 def ovs_vxlan_supported(from_ip='192.0.2.1', to_ip='192.0.2.2'):
@@ -551,3 +581,17 @@ def min_tx_rate_support():
                   devices_without_support)
         return False
     return True
+
+
+def ovn_nb_db_schema_port_group_supported():
+    try:
+        ver = _get_ovn_version(OVNCheckType.nb_db_schema)
+        minver = versionutils.convert_version_to_tuple(
+                 OVN_NB_DB_SCHEMA_PORT_GROUP)
+        if ver < minver:
+            return False
+    except (OSError, RuntimeError, ValueError) as e:
+        LOG.debug('Exception while checking OVN DB schema version. '
+                  'Exception: %s', e)
+        return False
+    return True

neutron/cmd/sanity_check.py

@@ -303,6 +303,14 @@ def check_min_tx_rate_support():
     return result
 
 
+def check_ovn_nb_db_schema_port_group_support():
+    result = checks.ovn_nb_db_schema_port_group_supported()
+    if not result:
+        LOG.warning('OVN NB DB schema does not support Port_Group. This '
+                    'support was added in DB schema version 5.11.')
+    return result
+
+
 # Define CLI opts to test specific features, with a callback for the test
 OPTS = [
     BoolOptCallback('ovs_vxlan', check_ovs_vxlan, default=False,
@@ -367,6 +375,10 @@ OPTS = [
                     help=_('Check if the configured SR-IOV NICs support '
                            'the "ip-link vf min_tx_rate" parameter.'),
                     default=False),
+    BoolOptCallback('ovn_nb_db_schema_port_group_support',
+                    check_ovn_nb_db_schema_port_group_support,
+                    help=_('Check OVN NB DB schema support Port_Group'),
+                    default=False),
 ]
 
 
@@ -413,6 +425,8 @@ def enable_tests_from_config():
         cfg.CONF.set_default('bridge_firewalling', True)
     if cfg.CONF.SRIOV_NIC.physical_device_mappings:
         cfg.CONF.set_default('check_min_tx_rate_support', True)
+    if 'ovn' in cfg.CONF.ml2.mechanism_drivers:
+        cfg.CONF.set_default('ovn_nb_db_schema_port_group_support', True)
 
 
 def all_tests_passed():

neutron/plugins/ml2/drivers/ovn/mech_driver/ovsdb/impl_idl_ovn.py

@@ -770,14 +770,7 @@ class OvsdbNbOvnIdl(nb_impl_idl.OvnNbApiIdlImpl, Backend):
     def get_port_group(self, pg_name):
         if uuidutils.is_uuid_like(pg_name):
             pg_name = utils.ovn_port_group_name(pg_name)
-        try:
         return self.lookup('Port_Group', pg_name, default=None)
-        except KeyError:
-            # TODO(dalvarez): This except block is added for backwards compat
-            # with old OVN schemas (<=2.9) where Port Groups are not present.
-            # This (and other conditional code around this feature) shall be
-            # removed at some point.
-            return
 
     def get_sg_port_groups(self):
         """Returns OVN port groups used as Neutron Security Groups.
@@ -787,7 +780,6 @@ class OvsdbNbOvnIdl(nb_impl_idl.OvnNbApiIdlImpl, Backend):
         SGs, it will also not be returned.
         """
         port_groups = {}
-        try:
         for row in self._tables['Port_Group'].rows.values():
             name = getattr(row, 'name')
             if not (ovn_const.OVN_SG_EXT_ID_KEY in row.external_ids or
@@ -797,12 +789,6 @@ class OvsdbNbOvnIdl(nb_impl_idl.OvnNbApiIdlImpl, Backend):
             for row_key in getattr(row, "_data", {}):
                 data[row_key] = getattr(row, row_key)
             port_groups[name] = data
-        except KeyError:
-            # TODO(dalvarez): This except block is added for backwards compat
-            # with old OVN schemas (<=2.9) where Port Groups are not present.
-            # This (and other conditional code around this feature) shall be
-            # removed at some point.
-            pass
         return port_groups
 
     def check_liveness(self):

neutron/tests/unit/plugins/ml2/drivers/ovn/mech_driver/ovsdb/test_impl_idl_ovn.py

@@ -14,7 +14,6 @@
 import collections
 import copy
 from unittest import mock
-import uuid
 
 from ovsdbapp.backend import ovs_idl
 
@@ -769,20 +768,6 @@ class TestNBImplIdlOvn(TestDBImplIdlOvn):
         address_sets = self.nb_ovn_idl.get_address_sets()
         self.assertEqual(len(address_sets), 4)
 
-    def test_get_port_group_not_supported(self):
-        self._load_nb_db()
-        # Make sure that PG tables doesn't exist in fake db.
-        self._tables.pop('Port_Group', None)
-        port_group = self.nb_ovn_idl.get_port_group(str(uuid.uuid4()))
-        self.assertIsNone(port_group)
-
-    def test_get_sg_port_groups_not_supported(self):
-        self._load_nb_db()
-        # Make sure that PG tables doesn't exist in fake db.
-        self._tables.pop('Port_Group', None)
-        port_groups = self.nb_ovn_idl.get_sg_port_groups()
-        self.assertEqual({}, port_groups)
-
     def test_get_router_floatingip_lbs(self):
         lrouter_name = 'rtr_name'
         # Empty

releasenotes/notes/ovn-supports-Port_Group-96fc1a89e2da163d.yaml

@@ -0,0 +1,7 @@
+---
+other:
+  - |
+    It is assumed now that OVN supports Northbound table ``Port_Group`` by
+    default. This table was added in the DB schema version 5.11. A sanity check
+    is included if OVN is defined in ``ml2.mechanism_drivers`` configuration
+    option.