ryu/lib/quantum_ifaces.py: track the relation of quantum iface-id

Based on the following patch:

From: Isaku Yamahata <yamahata@valinux.co.jp>
Date: Tue, 20 Nov 2012 12:21:51 +0900
Subject: ryu/lib/quantum_ifaces.py: track the relation of quantum iface-id

This is needed for quantum plugin in order to track the association
from iface-id to network id or other info.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

ryu/lib/quantum_ifaces.py

@@ -0,0 +1,131 @@
+# Copyright (C) 2012 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2012 Isaku Yamahata <yamahata at private email ne jp>
+#
+# 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.
+
+import logging
+
+from ryu.base import app_manager
+from ryu.controller import event
+
+LOG = logging.getLogger(__name__)
+
+
+class EventQuantumIfaceSet(event.EventBase):
+    def __init__(self, iface_id, key, value):
+        super(EventQuantumIfaceSet, self).__init__()
+        self.iface_id = iface_id
+        self.key = key
+        self.value = value
+
+    def __str__(self):
+        return 'EventQuantumIfaceSet<%s, %s, %s>' % (
+            self.iface_id, self.key, self.value)
+
+
+class QuantumIfaces(app_manager.RyuApp, dict):
+    # iface-id => dict
+    #    {'iface_id': {
+    #         'network_id': net-id,
+    #         'ports': [{'datapath_id': dpid, 'ofport': ofport, 'name': name}]
+    #     }}
+
+    KEY_NETWORK_ID = 'network_id'
+    KEY_PORTS = 'ports'
+    SUBKEY_DATAPATH_ID = 'datapath_id'
+    SUBKEY_OFPORT = 'ofport'
+    SUBKEY_NAME = 'name'
+
+    def __init__(self):
+        super(QuantumIfaces, self).__init__()
+        self.name = 'quantum_ifaces'
+
+    def register(self, iface_id):
+        self.setdefault(iface_id, {})
+
+    def unregister(self, iface_id):
+        del self[iface_id]
+
+    def get_iface_dict(self, iface_id):
+        return self[iface_id]
+
+    def list_keys(self, iface_id):
+        return self[iface_id].keys()
+
+    def get_key(self, iface_id, key):
+        return self[iface_id][key]
+
+    def _update_key(self, iface_id, key, value):
+        if key == self.KEY_PORTS:
+            ports = self[iface_id].setdefault(key, [])
+            try:
+                ports.remove(value)
+            except ValueError:
+                pass
+            ports.append(value)
+        else:
+            self[iface_id][key] = value
+        self.send_event_to_observers(
+            EventQuantumIfaceSet(iface_id, key, value))
+
+    def set_key(self, iface_id, key, value):
+        iface = self.setdefault(iface_id, {})
+        if key in iface:
+            raise ValueError('trying to set already existing value '
+                             '%s %s -> %s', key, iface[key], value)
+        self._update_key(iface_id, key, value)
+
+    def update_key(self, iface_id, key, value):
+        iface = self.setdefault(iface_id, {})
+        if key in iface:
+            err = False
+            if key == self.KEY_PORTS:
+                dpid = value.get(self.SUBKEY_DATAPATH_ID)
+                ofport = value.get(self.SUBKEY_OFPORT)
+                name = value.get(self.SUBKEY_NAME)
+                if not dpid or not ofport or not name:
+                    raise ValueError(
+                        'invalid port data: dpid=%s ofport=%s name=%s',
+                        dpid, ofport, name)
+                for p in iface[key]:
+                    if (p[self.SUBKEY_DATAPATH_ID] == dpid and
+                        (p[self.SUBKEY_OFPORT] != ofport or
+                         p[self.SUBKEY_NAME] != name)):
+                        err = True
+                        break
+            elif iface[key] != value:
+                err = True
+            if err:
+                raise ValueError('unmatched updated %s %s -> %s',
+                                 key, iface[key], value)
+        self._update_key(iface_id, key, value)
+
+    def del_key(self, iface_id, key, value=None):
+        if iface_id not in self or key not in self[iface_id]:
+            return
+
+        if key != self.KEY_PORTS:
+            assert value is None
+            del self[iface_id][key]
+            return
+
+        ports = self[iface_id][key]
+        try:
+            ports.remove(value)
+        except ValueError:
+            pass
+        if not ports:
+            del self[iface_id][key]
+            return
+        return True