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 xml.etree import cElementTree as ET

from common import BASE_NS

from common import qualify as _

class HelloParser:

    @staticmethod

    def parse(raw):

        'Returns tuple of (session-id, ["capability_uri", ...])'

        sid, capabilities = 0, []

        root = ET.fromstring(raw)

        if root.tag in ('hello', _('hello', BASE_NS)):

            for child in root.getchildren():

                if child.tag in ('session-id', _('session-id', BASE_NS)):

                    sid = child.text

                elif child.tag in ('capabilities', _('capabilities', BASE_NS)):

                    for cap in child.getiterator('capability'): 

                        capabilities.append(cap.text)

                    for cap in child.getiterator(_('capability', BASE_NS)):

                        capabilities.append(cap.text)

        return sid, capabilities

class RootParser:

    '''Parser for the top-level element of an XML document. Does not look at any

    sub-elements. It is useful for efficiently determining the type of received

    messages.

    '''

    def __init__(self, recognize=[]):

        self._recognized = recognize

    def recognize(self, element):

        '''Specify an element that should be successfully parsed.

        element should be a string that represents a qualified name of the form

        `{namespace}tag`.

        '''

        self._recognized.append(element)

    def parse(self, raw):

        '''Parse the top-level element from a string representing an XML document.

        Returns a `(tag, attributes)` tuple, where `tag` is a string representing

        the qualified name of the recognized element and `attributes` is an

        `{attribute: value}` dictionary.

        '''

        fp = StringIO(raw)

        for event, element in ET.iterparse(fp, events=('start',)):

            for ele in self._recognized:

                if element.tag == ele:

                    return (element.tag, element.attrib)

            break

        return None