Add snmp driver auto discovery

When instantiated, this new universal snmp driver chooses one
concrete snmp driver selected the prefix value of the
`SNMPv2-MIB::sysObjectID` MIB object looked up at the device.

Co-Authored-By: Ilya Etingof <etingof@gmail.com>
Change-Id: I9bf01a0c567048d0169db281684d16a00e39f6b8
Story: #1635644
Task: #10529

doc/source/admin/drivers/snmp.rst

@@ -116,7 +116,9 @@ set to the hardware type ``snmp``.
 The following property values have to be added to the node's
 ``driver_info`` field:
 
-- ``snmp_driver``: PDU manufacturer driver
+- ``snmp_driver``: PDU manufacturer driver name or ``auto`` to automatically
+  choose ironic snmp driver based on ``SNMPv2-MIB::sysObjectID`` value as
+  reported by PDU.
 - ``snmp_address``: the IPv4 address of the PDU controlling this node.
 - ``snmp_port``: (optional) A non-standard UDP port to use for SNMP operations.
   If not specified, the default port (161) is used.

ironic/drivers/modules/snmp.py

@@ -527,6 +527,7 @@ class SNMPDriverAten(SNMPDriverSimple):
     1.3.6.1.4.1.21317.1.3.2.2.2.2 Outlet Power
     Values: 1=Off, 2=On, 3=Pending, 4=Reset
     """
+    system_id = (21317,)
     oid_device = (21317, 1, 3, 2, 2, 2, 2)
     value_power_on = 2
     value_power_off = 1
@@ -548,6 +549,7 @@ class SNMPDriverAPCMasterSwitch(SNMPDriverSimple):
     Values: 1=On, 2=Off, 3=PowerCycle, [...more options follow]
     """
 
+    system_id = (318, 1, 1, 4)
     oid_device = (318, 1, 1, 4, 4, 2, 1, 3)
     value_power_on = 1
     value_power_off = 2
@@ -561,6 +563,7 @@ class SNMPDriverAPCMasterSwitchPlus(SNMPDriverSimple):
     Values: 1=On, 3=Off, [...more options follow]
     """
 
+    system_id = (318, 1, 1, 6)
     oid_device = (318, 1, 1, 6, 5, 1, 1, 5)
     value_power_on = 1
     value_power_off = 3
@@ -574,6 +577,7 @@ class SNMPDriverAPCRackPDU(SNMPDriverSimple):
     Values: 1=On, 2=Off, 3=PowerCycle, [...more options follow]
     """
 
+    system_id = (318, 1, 1, 12)
     oid_device = (318, 1, 1, 12, 3, 3, 1, 1, 4)
     value_power_on = 1
     value_power_off = 2
@@ -591,6 +595,7 @@ class SNMPDriverCyberPower(SNMPDriverSimple):
     #                 been implemented based upon its published MIB
     #                 documentation.
 
+    system_id = (3808,)
     oid_device = (3808, 1, 1, 3, 3, 3, 1, 1, 4)
     value_power_on = 1
     value_power_off = 2
@@ -604,6 +609,7 @@ class SNMPDriverTeltronix(SNMPDriverSimple):
     Values: 1=Off, 2=On
     """
 
+    system_id = (23620,)
     oid_device = (23620, 1, 2, 2, 1, 4)
     value_power_on = 2
     value_power_off = 1
@@ -628,6 +634,7 @@ class SNMPDriverEatonPower(SNMPDriverBase):
     #                 been implemented based upon its published MIB
     #                 documentation.
 
+    system_id = (534,)
     oid_device = (534, 6, 6, 7, 6, 6, 1)
     oid_status = (2,)
     oid_poweron = (3,)
@@ -688,6 +695,66 @@ class SNMPDriverEatonPower(SNMPDriverBase):
         self.client.set(oid, value)
 
 
+class SNMPDriverAuto(SNMPDriverBase):
+
+    SYS_OBJ_OID = (1, 3, 6, 1, 2, 1, 1, 2)
+
+    def __init__(self, *args, **kwargs):
+        super(SNMPDriverAuto, self).__init__(*args, **kwargs)
+
+        drivers_map = {}
+
+        for name, obj in DRIVER_CLASSES.items():
+            if not getattr(obj, 'system_id', False):
+                continue
+
+            system_id = self.oid_enterprise + getattr(obj, 'system_id')
+
+            if (system_id in drivers_map and
+                    drivers_map[system_id] is not obj):
+                raise exception.InvalidParameterValue(_(
+                    "SNMPDriverAuto: duplicate driver system ID prefix "
+                    "%(system_id)s") % {'system_id': system_id})
+
+            drivers_map[system_id] = obj
+            LOG.debug("SNMP driver mapping %(system_id)s -> %(name)s",
+                      {'system_id': system_id, 'name': obj.__name__})
+
+        system_id = self.client.get(self.SYS_OBJ_OID)
+
+        LOG.debug("SNMP device reports sysObjectID %(system_id)s",
+                  {'system_id': system_id})
+
+        system_id_prefix = tuple(system_id)
+
+        # pick driver by the longest matching sysObjectID prefix
+        while len(system_id_prefix) > len(self.oid_enterprise):
+            try:
+                Driver = drivers_map[system_id_prefix]
+                LOG.debug("Chosen SNMP driver %(name)s based on sysObjectID "
+                          "prefix %(system_id_prefix)s", {Driver.__name__,
+                                                          system_id_prefix})
+                self.driver = Driver(*args, **kwargs)
+                return
+
+            except KeyError:
+                system_id_prefix = system_id_prefix[:-1]
+
+        raise exception.InvalidParameterValue(_(
+            "SNMPDriverAuto: no driver matching %(system_id)s") %
+            {'system_id': system_id})
+
+    def _snmp_power_state(self):
+        current_power_state = self.driver._snmp_power_state()
+        return current_power_state
+
+    def _snmp_power_on(self):
+        return self.driver._snmp_power_on()
+
+    def _snmp_power_off(self):
+        return self.driver._snmp_power_off()
+
+
 # A dictionary of supported drivers keyed by snmp_driver attribute
 DRIVER_CLASSES = {
     'apc': SNMPDriverAPCMasterSwitch,
@@ -697,7 +764,8 @@ DRIVER_CLASSES = {
     'aten': SNMPDriverAten,
     'cyberpower': SNMPDriverCyberPower,
     'eatonpower': SNMPDriverEatonPower,
-    'teltronix': SNMPDriverTeltronix
+    'teltronix': SNMPDriverTeltronix,
+    'auto': SNMPDriverAuto
 }
 
 

ironic/tests/unit/drivers/modules/test_snmp.py

@@ -595,6 +595,19 @@ class SNMPDeviceDriverTestCase(db_base.DbTestCase):
 
     The SNMP client object is mocked to allow various error cases to be tested.
     """
+    pdus = {
+        (1, 3, 6, 1, 4, 1, 318, 1, 1, 4): 'apc_masterswitch',
+        # also try longer sysObjectID
+        (1, 3, 6, 1, 4, 1, 318, 1, 1, 4, 1, 2, 3, 4): 'apc_masterswitch',
+        (1, 3, 6, 1, 4, 1, 318, 1, 1, 6): 'apc_masterswitchplus',
+        (1, 3, 6, 1, 4, 1, 318, 1, 1, 12): 'apc_rackpdu',
+        (1, 3, 6, 1, 4, 1, 21317): 'aten',
+        (1, 3, 6, 1, 4, 1, 3808): 'cyberpower',
+        (1, 3, 6, 1, 4, 1, 23620): 'teltronix',
+        # TODO(etingof): SNMPDriverEatonPower misses the `.oid` attribute
+        # and therefore fails tests
+        # (1, 3, 6, 1, 4, 1, 534): 'eatonpower',
+    }
 
     def setUp(self):
         super(SNMPDeviceDriverTestCase, self).setUp()
@@ -1256,6 +1269,130 @@ class SNMPDeviceDriverTestCase(db_base.DbTestCase):
     def test_teltronix_power_reset(self, mock_get_client):
         self._test_simple_device_power_reset('teltronix', mock_get_client)
 
+    def test_auto_power_state_unknown_pdu(self, mock_get_client):
+        mock_client = mock_get_client.return_value
+        mock_client.get.return_value = 'unknown'
+        self._update_driver_info(snmp_driver="auto")
+        self.assertRaises(exception.InvalidParameterValue,
+                          snmp._get_driver,
+                          self.node)
+
+    def test_auto_power_state_pdu_discovery_failure(self, mock_get_client):
+        mock_client = mock_get_client.return_value
+        mock_client.get.side_effect = exception.SNMPFailure(operation='get',
+                                                            error='')
+        self._update_driver_info(snmp_driver="auto")
+        self.assertRaises(exception.SNMPFailure, snmp._get_driver, self.node)
+
+    def test_auto_power_state_on(self, mock_get_client):
+        for sys_obj_oid, expected_snmp_driver in self.pdus.items():
+            mock_client = mock_get_client.return_value
+            mock_client.reset_mock()
+            mock_client.get.return_value = sys_obj_oid
+            self._update_driver_info(snmp_driver="auto")
+            driver = snmp._get_driver(self.node)
+
+            second_node = obj_utils.get_test_node(
+                self.context,
+                driver='fake_snmp',
+                driver_info=INFO_DICT)
+            second_node["driver_info"].update(snmp_driver=expected_snmp_driver)
+            second_node_driver = snmp._get_driver(second_node)
+            mock_client.get.return_value = second_node_driver.value_power_on
+
+            pstate = driver.power_state()
+            mock_client.get.assert_called_with(second_node_driver.oid)
+            self.assertEqual(states.POWER_ON, pstate)
+
+    def test_auto_power_state_off(self, mock_get_client):
+        for sys_obj_oid, expected_snmp_driver in self.pdus.items():
+            mock_client = mock_get_client.return_value
+            mock_client.reset_mock()
+            mock_client.get.return_value = sys_obj_oid
+            self._update_driver_info(snmp_driver="auto")
+            driver = snmp._get_driver(self.node)
+
+            second_node = obj_utils.get_test_node(
+                self.context,
+                driver='fake_snmp',
+                driver_info=INFO_DICT)
+            second_node["driver_info"].update(snmp_driver=expected_snmp_driver)
+            second_node_driver = snmp._get_driver(second_node)
+            mock_client.get.return_value = second_node_driver.value_power_off
+
+            pstate = driver.power_state()
+            mock_client.get.assert_called_with(second_node_driver.oid)
+            self.assertEqual(states.POWER_OFF, pstate)
+
+    def test_auto_power_on(self, mock_get_client):
+        for sys_obj_oid, expected_snmp_driver in self.pdus.items():
+            mock_client = mock_get_client.return_value
+            mock_client.reset_mock()
+            mock_client.get.return_value = sys_obj_oid
+            self._update_driver_info(snmp_driver="auto")
+            driver = snmp._get_driver(self.node)
+
+            second_node = obj_utils.get_test_node(
+                self.context,
+                driver='fake_snmp',
+                driver_info=INFO_DICT)
+            second_node["driver_info"].update(snmp_driver=expected_snmp_driver)
+            second_node_driver = snmp._get_driver(second_node)
+            mock_client.get.return_value = second_node_driver.value_power_on
+
+            pstate = driver.power_on()
+            mock_client.set.assert_called_once_with(
+                second_node_driver.oid,
+                second_node_driver.value_power_on)
+            self.assertEqual(states.POWER_ON, pstate)
+
+    def test_auto_power_off(self, mock_get_client):
+        for sys_obj_oid, expected_snmp_driver in self.pdus.items():
+            mock_client = mock_get_client.return_value
+            mock_client.reset_mock()
+            mock_client.get.return_value = sys_obj_oid
+            self._update_driver_info(snmp_driver="auto")
+            driver = snmp._get_driver(self.node)
+
+            second_node = obj_utils.get_test_node(
+                self.context,
+                driver='fake_snmp',
+                driver_info=INFO_DICT)
+            second_node["driver_info"].update(snmp_driver=expected_snmp_driver)
+            second_node_driver = snmp._get_driver(second_node)
+            mock_client.get.return_value = second_node_driver.value_power_off
+
+            pstate = driver.power_off()
+            mock_client.set.assert_called_once_with(
+                second_node_driver.oid,
+                second_node_driver.value_power_off)
+            self.assertEqual(states.POWER_OFF, pstate)
+
+    def test_auto_power_reset(self, mock_get_client):
+        for sys_obj_oid, expected_snmp_driver in self.pdus.items():
+            mock_client = mock_get_client.return_value
+            mock_client.reset_mock()
+            mock_client.get.side_effect = [sys_obj_oid, sys_obj_oid]
+            self._update_driver_info(snmp_driver="auto")
+            driver = snmp._get_driver(self.node)
+
+            second_node = obj_utils.get_test_node(
+                self.context,
+                driver='fake_snmp',
+                driver_info=INFO_DICT)
+            second_node["driver_info"].update(snmp_driver=expected_snmp_driver)
+            second_node_driver = snmp._get_driver(second_node)
+            mock_client.get.side_effect = [second_node_driver.value_power_off,
+                                           second_node_driver.value_power_on]
+
+            pstate = driver.power_reset()
+            calls = [mock.call(second_node_driver.oid,
+                               second_node_driver.value_power_off),
+                     mock.call(second_node_driver.oid,
+                               second_node_driver.value_power_on)]
+            mock_client.set.assert_has_calls(calls)
+            self.assertEqual(states.POWER_ON, pstate)
+
     def test_eaton_power_snmp_objects(self, mock_get_client):
         # Ensure the correct SNMP object OIDs and values are used by the Eaton
         # Power driver

releasenotes/notes/add-snmp-pdu-driver-type-discovery-1f280b7f06fd1ca5.yaml

@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    Adds new ``auto`` type of the ``driver_info/snmp_driver`` setting which
+    makes ironic automatically select a suitable SNMP driver type based on
+    the ``SNMPv2-MIB::sysObjectID`` value as reported by the PDU being
+    managed.