1 files changed, 104 insertions, 0 deletions
diff --git a/networking_sfc/services/flowclassifier/driver_manager.py b/networking_sfc/services/flowclassifier/driver_manager.py
new file mode 100644
index 0000000..1af4470
--- /dev/null
+++ b/networking_sfc/services/flowclassifier/driver_manager.py
@@ -0,0 +1,104 @@
+# Copyright 2015 Futurewei. All rights reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from oslo_config import cfg
+from oslo_log import log
+import stevedore
+
+from neutron.i18n import _LE
+from neutron.i18n import _LI
+
+from networking_sfc.services.flowclassifier.common import exceptions as fc_exc
+
+
+LOG = log.getLogger(__name__)
+cfg.CONF.import_opt('drivers',
+                    'networking_sfc.services.flowclassifier.common.config',
+                    group='flowclassifier')
+
+
+class FlowClassifierDriverManager(stevedore.named.NamedExtensionManager):
+    """Implementation of Flow Classifier drivers."""
+
+    def __init__(self):
+        # Registered flow classifier drivers, keyed by name.
+        self.drivers = {}
+        # Ordered list of flow classifier drivers, defining
+        # the order in which the drivers are called.
+        self.ordered_drivers = []
+        LOG.info(_LI("Configured Flow Classifier drivers: %s"),
+                 cfg.CONF.flowclassifier.drivers)
+        super(FlowClassifierDriverManager, self).__init__(
+            'networking_sfc.flowclassifier.drivers',
+            cfg.CONF.flowclassifier.drivers,
+            invoke_on_load=True,
+            name_order=True)
+        LOG.info(_LI("Loaded Flow Classifier drivers: %s"),
+                 self.names())
+        self._register_drivers()
+
+    def _register_drivers(self):
+        """Register all Flow Classifier drivers.
+
+        This method should only be called once in the
+        FlowClassifierDriverManager constructor.
+        """
+        for ext in self:
+            self.drivers[ext.name] = ext
+            self.ordered_drivers.append(ext)
+        LOG.info(_LI("Registered Flow Classifier drivers: %s"),
+                 [driver.name for driver in self.ordered_drivers])
+
+    def initialize(self):
+        # ServiceChain bulk operations requires each driver to support them
+        self.native_bulk_support = True
+        for driver in self.ordered_drivers:
+            LOG.info(_LI("Initializing Flow Classifier driver '%s'"),
+                     driver.name)
+            driver.obj.initialize()
+            self.native_bulk_support &= getattr(driver.obj,
+                                                'native_bulk_support', True)
+
+    def _call_drivers(self, method_name, context):
+        """Helper method for calling a method across all drivers.
+
+        :param method_name: name of the method to call
+        :param context: context parameter to pass to each method call
+        :param continue_on_failure: whether or not to continue to call
+        all SFC drivers once one has raised an exception
+        if any Flow Classifier driver call fails.
+        """
+        for driver in self.ordered_drivers:
+            try:
+                getattr(driver.obj, method_name)(context)
+            except Exception as e:
+                # This is an internal failure.
+                LOG.exception(e)
+                LOG.error(
+                    _LE("Flow Classifier driver '%(name)s'"
+                        "failed in %(method)s"),
+                    {'name': driver.name, 'method': method_name}
+                )
+                raise fc_exc.FlowClassifierDriverError(
+                    method=method_name
+                )
+
+    def create_flow_classifier(self, context):
+        self._call_drivers("create_flow_classifier", context)
+
+    def update_flow_classifier(self, context):
+        self._call_drivers("update_flow_classifier", context)
+
+    def delete_flow_classifier(self, context):
+        self._call_drivers("delete_flow_classifier", context)