1# Copyright (C) 2017 Nippon Telegraph and Telephone Corporation. 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# http://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 12# implied. 13# See the License for the specific language governing permissions and 14# limitations under the License. 15 16""" 17Events for Zebra protocol service. 18""" 19 20import inspect 21import logging 22 23from ryu import utils 24from ryu.controller import event 25from ryu.lib.packet import zebra 26 27 28LOG = logging.getLogger(__name__) 29MOD = utils.import_module(__name__) 30 31ZEBRA_EVENTS = [] 32 33 34class EventZebraBase(event.EventBase): 35 """ 36 The base class for Zebra protocol service event class. 37 38 The subclasses have at least ``zclient`` and the same attributes with 39 :py:class: `ryu.lib.packet.zebra.ZebraMessage`. 40 ``zclient`` is an instance of Zebra client class. See 41 :py:class: `ryu.services.protocols.zebra.client.zclient.ZClient` or 42 :py:class: `ryu.services.protocols.zebra.server.zserver.ZClient`. 43 44 The subclasses are named as:: 45 46 ``"Event" + <Zebra message body class name>`` 47 48 For Example, if the service received ZEBRA_INTERFACE_ADD message, 49 the body class should be 50 :py:class: `ryu.lib.packet.zebra.ZebraInterfaceAdd`, then the event 51 class will be named as:: 52 53 "Event" + "ZebraInterfaceAdd" = "EventZebraInterfaceAdd" 54 55 ``msg`` argument must be an instance of 56 :py:class: `ryu.lib.packet.zebra.ZebraMessage` and used to extract the 57 attributes for the event classes. 58 """ 59 60 def __init__(self, zclient, msg): 61 super(EventZebraBase, self).__init__() 62 assert isinstance(msg, zebra.ZebraMessage) 63 self.__dict__ = msg.__dict__ 64 self.zclient = zclient 65 66 def __repr__(self): 67 m = ', '.join( 68 ['%s=%r' % (k, v) 69 for k, v in self.__dict__.items() if not k.startswith('_')]) 70 return "%s(%s)" % (self.__class__.__name__, m) 71 72 __str__ = __repr__ 73 74 75def _event_name(body_cls): 76 return 'Event%s' % body_cls.__name__ 77 78 79def message_to_event(zclient, msg): 80 """ 81 Converts Zebra protocol message instance to Zebra protocol service 82 event instance. 83 84 If corresponding event class is not defined, returns None. 85 86 :param zclient: Zebra client instance. 87 :param msg: Zebra protocol message. 88 :return: Zebra protocol service event. 89 """ 90 if not isinstance(msg, zebra.ZebraMessage): 91 return None 92 93 body_cls = msg.get_body_class(msg.version, msg.command) 94 ev_cls = getattr(MOD, _event_name(body_cls), None) 95 if ev_cls is None: 96 return None 97 98 return ev_cls(zclient, msg) 99 100 101def _define_event_class(body_cls): 102 name = _event_name(body_cls) 103 104 event_cls = type(name, (EventZebraBase,), {}) 105 globals()[name] = event_cls 106 107 return event_cls 108 109 110def _generate_event_classes(): 111 for zebra_cls in zebra.__dict__.values(): 112 if (not inspect.isclass(zebra_cls) 113 or not issubclass(zebra_cls, zebra._ZebraMessageBody) 114 or zebra_cls.__name__.startswith('_')): 115 continue 116 117 ev = _define_event_class(zebra_cls) 118 # LOG.debug('Generated Zebra event: %s' % ev) 119 ZEBRA_EVENTS.append(ev) 120 121 122_generate_event_classes() 123