Allow unset port's host_id

It is supported by Neutron and needs to be done like that when e.g.
admin wants to unbound port from the host.

Task: #44043
Story: #2009705
Change-Id: I08f1bb40f4dc72cfa7c62feeb5f513455de0ca45

Author: slawqo

openstackclient/network/v2/port.py

@@ -969,6 +969,12 @@ def get_parser(self, prog_name):
             action='store_true',
             help=_("Clear existing NUMA affinity policy")
         )
+        parser.add_argument(
+            '--host',
+            action='store_true',
+            default=False,
+            help=_("Clear host binding for the port.")
+        )
 
         _tag.add_tag_option_to_parser_for_unset(parser, _('port'))
 
@@ -1026,6 +1032,8 @@ def take_action(self, parsed_args):
             attrs['data_plane_status'] = None
         if parsed_args.numa_policy:
             attrs['numa_affinity_policy'] = None
+        if parsed_args.host:
+            attrs['binding:host_id'] = None
 
         attrs.update(
             self._parse_extra_properties(parsed_args.extra_properties))

openstackclient/tests/unit/network/v2/test_port.py

@@ -1923,6 +1923,7 @@ def test_unset_port_parameters(self):
             'subnet=042eb10a-3a18-4658-ab-cf47c8d03152,ip-address=1.0.0.0',
             '--binding-profile', 'Superman',
             '--qos-policy',
+            '--host',
             self._testport.name,
         ]
         verifylist = [
@@ -1931,6 +1932,7 @@ def test_unset_port_parameters(self):
                 'ip-address': '1.0.0.0'}]),
             ('binding_profile', ['Superman']),
             ('qos_policy', True),
+            ('host', True)
         ]
 
         parsed_args = self.check_parser(self.cmd, arglist, verifylist)
@@ -1941,7 +1943,8 @@ def test_unset_port_parameters(self):
                 'subnet_id': '042eb10a-3a18-4658-ab-cf47c8d03152',
                 'ip_address': '0.0.0.1'}],
             'binding:profile': {'batman': 'Joker'},
-            'qos_policy_id': None
+            'qos_policy_id': None,
+            'binding:host_id': None
         }
         self.network.update_port.assert_called_once_with(
             self._testport, **attrs)

releasenotes/notes/add-option-to-unset-port-host-c76de9b1d2addf9a.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Add possibility to unbind Neutron's port from the host by unsetting its
+    host_id.