ncclient:NETCONF Python client

# Copyright 2009 Shikhar Bhushan

#

# 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 threading import Event, Lock

from uuid import uuid1

from . import logger

class RPC:

    def __init__(self, session, async=False):

        self._session = session

        self._id = uuid1().urn

        self._reply = RPCReply()

        self._reply_event = Event()

    def _build(self, op, encoding='utf-8'):

        if isinstance(op, basestring):

            return RPCBuilder.build_from_string(self._id, op, encoding)

        else:

            return RPCBuilder.build_from_spec(self._id, op, encoding)

    def _request(self, op):

        self._reply = RPCReply()

        # get the listener instance for this session

        # <rpc-reply> with message id will reach response_cb

        self._listener.register(self._id, self)

        # only effective the first time, transport.session.Subject internally

        # uses a set type for listeners

        self._session.add_listener(self._listener)

        req = RPCBuilder.build(self._id, op)

        self._session.send(req)

        if reply_event is not None: # if we were provided an Event to use

            self._reply_event = reply_event

        else: # otherwise, block till response received and return it

            self._reply_event = Event()

            self._reply_event.wait()

            self._reply.parse()

        return self._reply

    def request(self, *args, **kwds):

        raise NotImplementedError

    @property

    def has_reply(self):

        try:

            return self._reply_event.isSet()

        except TypeError: # reply_event is None

            return False

    @property

    def reply(self):

        return self._reply

    @property

    def id(self):

        return self._id

    @property

    def session(self):

        return self._session

    @staticmethod

    def build_from_spec(msgid, opspec, encoding='utf-8'):

        "TODO: docstring"

        spec = {

            'tag': _('rpc', BASE_NS),

            'attributes': {'message-id': msgid},

            'children': opspec

            }

        return TreeBuilder(spec).to_string(encoding)

    @staticmethod

    def build_from_string(msgid, opstr, encoding='utf-8'):

        "TODO: docstring"

        decl = '<?xml version="1.0" encoding="%s"?>' % encoding

        doc = (u'''<rpc message-id="%s" xmlns="%s">%s</rpc>''' %

               (msgid, BASE_NS, opstr)).encode(encoding)

        return (decl + doc)