Avoid race conditions

Sometimes the port pair group gets created before port pair was
committed in openstack. Before creating the port pair group, we check
that the port pair is already listed by openstack

Change-Id: Icfd23521859fc5d4e6bb6745be80f79bf9e31a0c
Signed-off-by: Manuel Buil <mbuil@suse.com>
(cherry picked from commit 52e86db6e0a3343852c9aabba49dffe3d699d1a0)

2 files changed, 51 insertions, 0 deletions

diff --git a/sfc/lib/openstack_utils.py b/sfc/lib/openstack_utils.py
index 7915e77d..38ca61bb 100644
--- a/sfc/lib/openstack_utils.py
+++ b/sfc/lib/openstack_utils.py
@@ -316,6 +316,23 @@ class OpenStackSFC:
                            {'vnf': vm_instance.name})
             return None
 
+        # Avoid race conditions by checking the port pair is already committed
+        iterations = 5
+        found_it = False
+        for i in range(iterations):
+            pp_list = self.neutron.list_sfc_port_pairs()['port_pairs']
+            for pp in pp_list:
+                if pp['id'] == port_pair_info['port_pair']['id']:
+                    found_it = True
+                    break
+            if found_it:
+                break
+            else:
+                time.sleep(3)
+
+        if not found_it:
+            raise Exception("Port pair was not committed in openstack")
+
         logger.info("Creating the port pair groups for %s" % vm_instance.name)
         port_pair_group = {}
         port_pair_group['name'] = vm_instance.name + '-port-pair-group'
diff --git a/sfc/unit_tests/unit/lib/test_openstack_utils.py b/sfc/unit_tests/unit/lib/test_openstack_utils.py
index 595aed0e..e41f90ab 100644
--- a/sfc/unit_tests/unit/lib/test_openstack_utils.py
+++ b/sfc/unit_tests/unit/lib/test_openstack_utils.py
@@ -715,6 +715,36 @@ class SfcOpenStackUtilsTesting(unittest.TestCase):
     @patch('snaps.domain.network.Port', autospec=True)
     @patch('snaps.domain.vm_inst.VmInst', autospec=True)
     @patch('sfc.lib.openstack_utils.logger', autospec=True)
+    def test_create_port_groups_exception_nopp(self, mock_log, mock_osvm,
+                                               mock_port):
+        """
+        Checks the create_port_groups when openstack does not commit the pp
+        """
+
+        log_calls_info = [call('Creating the port pairs for vm')]
+        mock_port_ins = mock_port.return_value
+        mock_port_ins.id = '123abc'
+        mock_vm_ins = mock_osvm.return_value
+        mock_vm_ins.name = 'vm'
+        exception_message = "Port pair was not committed in openstack"
+        expected_port_pair = {'name': 'vm-connection-points',
+                              'description': 'port pair for vm',
+                              'ingress': '123abc',
+                              'egress': '123abc'}
+        self.neutron.create_sfc_port_pair.return_value = \
+            {'port_pair': {'id': 'pp_id'}}
+        self.neutron.list_sfc_port_pairs.return_value = \
+            {'port_pairs': [{'id': 'xxxx'}]}
+        with self.assertRaises(Exception) as cm:
+            self.os_sfc.create_port_groups([mock_port_ins], mock_vm_ins)
+        self.assertEqual(exception_message, cm.exception.message)
+        self.neutron.create_sfc_port_pair.assert_has_calls(
+            [call({'port_pair': expected_port_pair})])
+        mock_log.info.assert_has_calls(log_calls_info)
+
+    @patch('snaps.domain.network.Port', autospec=True)
+    @patch('snaps.domain.vm_inst.VmInst', autospec=True)
+    @patch('sfc.lib.openstack_utils.logger', autospec=True)
     def test_create_port_groups_returns_none_from_ppg(self, mock_log,
                                                       mock_vm,
                                                       mock_port):
@@ -732,6 +762,8 @@ class SfcOpenStackUtilsTesting(unittest.TestCase):
         mock_port_ins.id = '123abc'
         self.neutron.create_sfc_port_pair.return_value = \
             {'port_pair': {'id': 'pp_id'}}
+        self.neutron.list_sfc_port_pairs.return_value = \
+            {'port_pairs': [{'id': 'pp_id'}]}
         self.neutron.create_sfc_port_pair_group.return_value = None
         result = self.os_sfc.create_port_groups([mock_port_ins], mock_vm_ins)
         self.assertIsNone(result)
@@ -759,6 +791,8 @@ class SfcOpenStackUtilsTesting(unittest.TestCase):
                               'egress': '123abc'}
         self.neutron.create_sfc_port_pair.return_value = \
             {'port_pair': {'id': 'pp_id'}}
+        self.neutron.list_sfc_port_pairs.return_value = \
+            {'port_pairs': [{'id': 'pp_id'}]}
         self.neutron.create_sfc_port_pair_group.return_value = \
             {'port_pair_group': {'id': 'pp_id'}}
         expected_port_pair_gr = {'name': 'vm-port-pair-group',