common/python/rift/mano/ncclient.py

   1
   2 #
   3 #   Copyright 2016 RIFT.IO Inc
   4 #
   5 #   Licensed under the Apache License, Version 2.0 (the "License");
   6 #   you may not use this file except in compliance with the License.
   7 #   You may obtain a copy of the License at
   8 #
   9 #       http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 #   Unless required by applicable law or agreed to in writing, software
  12 #   distributed under the License is distributed on an "AS IS" BASIS,
  13 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 #   See the License for the specific language governing permissions and
  15 #   limitations under the License.
  16 #
  17
  18 import time
  19 import asyncio
  20 import ncclient
  21 import ncclient.asyncio_manager
  22
  23 from gi.repository import RwYang
  24 class ProxyConnectionError(Exception):
  25     pass
  26
  27
  28 class NcClient(object):
  29     '''Class representing a Netconf Session'''
  30
  31     OPERATION_TIMEOUT_SECS = 240
  32
  33     def __init__(self, host, port, username, password, loop):
  34         '''Initialize a new Netconf Session instance
  35
  36         Arguments:
  37             host - host ip
  38             port - host port
  39             username - credentials for accessing the host, username
  40             password - credentials for accessing the host, password
  41
  42         Returns:
  43             A newly initialized Netconf session instance
  44         '''
  45         self.host = host
  46         self.port = port
  47         self.username = username
  48         self.password = password
  49         self.loop = loop
  50         self._nc_mgr = None
  51
  52         self._model = RwYang.Model.create_libyang()
  53
  54     @asyncio.coroutine
  55     def connect(self, timeout=240):
  56         '''Connect Netconf Session
  57
  58         Arguments:
  59             timeout - maximum time allowed before connect fails [default 30s]
  60         '''
  61         # logger.info("Connecting to confd (%s) SSH port (%s)", self.host, self.port)
  62         if self._nc_mgr:
  63             return
  64
  65         start_time = time.time()
  66         while (time.time() - start_time) < timeout:
  67             try:
  68                 self._nc_mgr = yield from ncclient.asyncio_manager.asyncio_connect(
  69                     loop=self.loop,
  70                     host=self.host,
  71                     port=self.port,
  72                     username=self.username,
  73                     password=self.password,
  74                     # Setting allow_agent and look_for_keys to false will skip public key
  75                     # authentication, and use password authentication.
  76                     allow_agent=False,
  77                     look_for_keys=False,
  78                     hostkey_verify=False)
  79
  80                 # logger.info("Successfully connected to confd (%s) SSH port (%s)", self.host, self.port)
  81                 self._nc_mgr.timeout = NcClient.OPERATION_TIMEOUT_SECS
  82                 return
  83
  84             except ncclient.NCClientError as e:
  85                 # logger.debug("Could not connect to (%s) confd ssh port (%s): %s",
  86                 #         self.host, self.port, str(e))
  87                 pass
  88
  89             yield from asyncio.sleep(5, loop=self.loop)
  90
  91         raise ProxyConnectionError("Could not connect to Confd ({}) ssh port ({}): within the timeout {} sec.".format(
  92                 self.host, self.port, timeout))
  93
  94     def convert_to_xml(self, module, yang_obj):
  95         schema =  getattr(module, "get_schema")
  96         self._model.load_schema_ypbc(schema())
  97
  98         get_xml = getattr(yang_obj, "to_xml_v2")
  99
 100         return get_xml(self._model)
 101
 102     @property
 103     def manager(self):
 104         return self._nc_mgr