oVirt driver: Close connection after each API call

Currently a new connection is created for every API call which is
never closed. This results in open connections accumulating over time
due to periodic calls like power state polling, which is further
compounded by the number of ovirt nodes deployed.

This change converts _getvm into a generator based context manager so
that the connection can be closed after every call.

Change-Id: I30f9695c591f72dae21467b0b31f6f67fad7cc8a

ironic_staging_drivers/ovirt/ovirt.py

@@ -19,6 +19,9 @@ via oVirt sdk API.
 
 For use in dev and test environments.
 """
+
+import contextlib
+
 from ironic.common import boot_devices
 from ironic.common import exception
 from ironic.common.i18n import _
@@ -123,6 +126,7 @@ def _parse_driver_info(node):
     return driver_info
 
 
+@contextlib.contextmanager
 def _getvm(driver_info):
     address = driver_info['ovirt_address']
     username = driver_info['ovirt_username']
@@ -149,15 +153,20 @@ def _getvm(driver_info):
                                     ca_file=ca_file)
         vms_service = connection.system_service().vms_service()
         vmsearch = vms_service.list(search='name=%s' % name)
+        if vmsearch:
+            yield vms_service.vm_service(vmsearch[0].id)
+        else:
+            raise staging_exception.OVirtError(_("VM with name "
+                                                 "%s was not found") % name)
     except sdk.Error as e:
         LOG.error("Could not fetch information about VM vm %(name)s, "
                   "got error: %(error)s", {'name': name, 'error': e})
         raise staging_exception.OVirtError(err=e)
-    if vmsearch:
-        return vms_service.vm_service(vmsearch[0].id)
-    else:
-        raise staging_exception.OVirtError(_("VM with name "
-                                             "%s was not found") % name)
+    finally:
+        try:
+            connection.close()
+        except sdk.Error as e:
+            LOG.warning("Error closing connection: %(error)s", {'error': e})
 
 
 class OVirtPower(base.PowerInterface):
@@ -188,7 +197,7 @@ class OVirtPower(base.PowerInterface):
         """
         driver_info = _parse_driver_info(task.node)
         vm_name = driver_info['ovirt_vm_name']
-        vm = _getvm(driver_info)
+        with _getvm(driver_info) as vm:
             status = vm.get().status.value
         if status not in OVIRT_TO_IRONIC_POWER_MAPPING:
             msg = ("oVirt returned unknown state for node %(node)s "
@@ -213,7 +222,7 @@ class OVirtPower(base.PowerInterface):
         """
         driver_info = _parse_driver_info(task.node)
         vm_name = driver_info['ovirt_vm_name']
-        vm = _getvm(driver_info)
+        with _getvm(driver_info) as vm:
             try:
                 if target_state == states.POWER_OFF:
                     vm.stop()
@@ -231,7 +240,8 @@ class OVirtPower(base.PowerInterface):
                     raise exception.InvalidParameterValue(msg)
             except sdk.Error as e:
                 LOG.error("Could not change status of VM vm %(name)s "
-                      "got error: %(error)s", {'name': vm_name, 'error': e})
+                          "got error: %(error)s",
+                          {'name': vm_name, 'error': e})
                 raise staging_exception.OVirtError(err=e)
 
     @task_manager.require_exclusive_lock
@@ -291,7 +301,7 @@ class OVirtManagement(base.ManagementInterface):
             oVirt operation.
         """
         driver_info = _parse_driver_info(task.node)
-        vm = _getvm(driver_info)
+        with _getvm(driver_info) as vm:
             boot_dev = vm.os.boot[0].get_dev()
         persistent = True
         ironic_boot_dev = OVIRT_TO_IRONIC_DEVICE_MAPPING.get(boot_dev)
@@ -324,7 +334,7 @@ class OVirtManagement(base.ManagementInterface):
                 "Invalid boot device %s specified.") % device)
 
         driver_info = _parse_driver_info(task.node)
-        vm = _getvm(driver_info)
+        with _getvm(driver_info) as vm:
             try:
                 boot = otypes.Boot(devices=[otypes.BootDevice(boot_dev)])
                 bootos = otypes.OperatingSystem(boot=boot)

ironic_staging_drivers/tests/unit/ovirt/test_ovirt.py

@@ -61,7 +61,7 @@ class OVirtDriverTestCase(db_base.DbTestCase):
         self.node['driver_info']['ovirt_address'] = u'127.0.0.1'
         driver_info = ovirt_power._parse_driver_info(self.node)
 
-        ovirt_power._getvm(driver_info)
+        with ovirt_power._getvm(driver_info):
             ovirt_power.sdk.Connection.assert_called_with(
                 ca_file=None, insecure='False', password='changeme',
                 url=b'https://127.0.0.1/ovirt-engine/api',
@@ -70,12 +70,14 @@ class OVirtDriverTestCase(db_base.DbTestCase):
         url = ovirt_power.sdk.Connection.mock_calls[0][-1]['url']
         self.assertIsInstance(url, bytes)
 
+        ovirt_power.sdk.Connection.return_value.close.assert_called()
+
     @mock.patch.object(ovirt_power, "sdk", create=True)
     def test_getvm_unicode(self, sdk):
         self.node['driver_info']['ovirt_address'] = u'host\u20141'
         driver_info = ovirt_power._parse_driver_info(self.node)
 
-        ovirt_power._getvm(driver_info)
+        with ovirt_power._getvm(driver_info):
             ovirt_power.sdk.Connection.assert_called_with(
                 ca_file=None, insecure='False', password='changeme',
                 url=u'https://host\u20141/ovirt-engine/api',
@@ -83,6 +85,7 @@ class OVirtDriverTestCase(db_base.DbTestCase):
             )
         url = ovirt_power.sdk.Connection.mock_calls[0][-1]['url']
         self.assertIsInstance(url, str)
+        ovirt_power.sdk.Connection.return_value.close.assert_called()
 
     def test_get_properties(self):
         expected = list(ovirt_power.PROPERTIES.keys())
@@ -137,18 +140,28 @@ class OVirtDriverTestCase(db_base.DbTestCase):
             mock_power.assert_called_once_with(task.driver.management, task,
                                                boot_devices.DISK)
 
-    @mock.patch.object(ovirt_power, '_getvm')
-    def test_set_reboot_when_down(self, mock_vm):
-        mock_vm.return_value.get.return_value.status.value = 'down'
+    @mock.patch.object(ovirt_power, "sdk", create=True)
+    def test_set_reboot_when_down(self, sdk):
+        vm = mock.Mock()
+        vm.get.return_value.status.value = 'down'
+        conn = sdk.Connection.return_value
+        vms_service = conn.system_service.return_value.vms_service.return_value
+        vms_service.vm_service.return_value = vm
 
         with task_manager.acquire(self.context, self.node.uuid) as task:
             task.driver.power.reboot(task)
-            mock_vm.return_value.start.assert_called_once()
+        vm.start.assert_called_once()
+        conn.close.assert_called()
 
-    @mock.patch.object(ovirt_power, '_getvm')
-    def test_set_reboot_when_up(self, mock_vm):
-        mock_vm.return_value.get.return_value.status.value = 'up'
+    @mock.patch.object(ovirt_power, "sdk", create=True)
+    def test_set_reboot_when_up(self, sdk):
+        vm = mock.Mock()
+        vm.get.return_value.status.value = 'up'
+        conn = sdk.Connection.return_value
+        vms_service = conn.system_service.return_value.vms_service.return_value
+        vms_service.vm_service.return_value = vm
 
         with task_manager.acquire(self.context, self.node.uuid) as task:
             task.driver.power.reboot(task)
-            mock_vm.return_value.reboot.assert_called_once()
+        vm.reboot.assert_called_once()
+        conn.close.assert_called()

releasenotes/notes/ovirt-close-conn-2f87f0312be044a5.yaml

@@ -0,0 +1,9 @@
+---
+fixes:
+  - |
+    oVirt driver: Close connection after each API call
+    
+    A new connection was being created for every API call which was
+    never closed. This resulted in open connections accumulating over time
+    due to periodic calls like power state polling, which was further
+    compounded by the number of ovirt nodes deployed.