1 files changed, 139 insertions, 0 deletions
diff --git a/examples/ncclient/diff_xml.py b/examples/ncclient/diff_xml.py
new file mode 100755
index 000000000..e21773425
--- /dev/null
+++ b/examples/ncclient/diff_xml.py
@@ -0,0 +1,139 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2019 Cisco and/or its affiliates.
+# 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.
+
+"""
+Usage: {prog} [OPTION] FILE1 FILE2 xPath
+
+Compare two XML files, while sorting elements.
+
+xPath optional parameter
+example:
+    ./{{urn:ietf:params:xml:ns:yang:ietf-interfaces}}interfaces/
+    {{urn:ietf:params:xml:ns:yang:ietf-interfaces}}interface[
+    {{urn:ietf:params:xml:ns:yang:ietf-interfaces}}name='loop0']
+"""
+import os
+import re
+import subprocess
+import sys
+from tempfile import NamedTemporaryFile
+from xml.etree import ElementTree
+from xml.etree.ElementTree import Element
+
+TAG_PATTERN = re.compile(r"""({(?P<namespace>[a-zA-Z0-9.:@\-/]+)}(?P<tag>[0-9a-zA-Z\-]+))|(?P<name>[0-9a-zA-Z\-]+)""",
+                         re.VERBOSE)
+PREFIX_PATTERN = re.compile(r"""(((urn)|(.+://))[a-zA-Z0-9.:@\-/]+[:/](?P<prefix>[0-9a-zA-Z\-]+))""", re.VERBOSE)
+
+if sys.version_info < (3, 0):
+    # Python 2
+    import codecs
+
+    def unicode_writer(fp):
+        return codecs.getwriter('utf-8')(fp)
+else:
+    # Python 3
+    def unicode_writer(fp):
+        return fp
+
+
+def print_usage(program):
+    print(__doc__.format(prog=program).strip())
+
+
+def parse_namespace(namespace):
+    """
+    Extracts module name fom namespace.
+    example:
+        urn:ietf:params:xml:ns:yang:ietf-nat -> ietf-nat
+        http://fd.io/hc2vpp/yang/vpp-fib-table-management -> vpp-fib-table-management
+        https://fd.io/hc2vpp/yang/vpp-fib-table-management -> vpp-fib-table-management
+    :param namespace: namespace in urn or http format
+    :return: module name from namespace
+    """
+    matcher = PREFIX_PATTERN.match(namespace)
+    if matcher.group("prefix"):
+        return matcher.group("prefix").lower()
+
+
+def sort(xml_element):
+    """
+    Sorts elements in xml in alphabetical order.
+    :param xml_element: root element of xml
+    """
+    if not isinstance(xml_element, Element):
+        exit(-1)
+    xml_element[:] = sorted(xml_element, key=lambda child: child.tag)
+
+    mo = TAG_PATTERN.match(xml_element.tag)
+    if mo.group("namespace") and mo.group("tag") and not mo.group("namespace").__contains__(
+            "urn:ietf:params:xml:ns:netconf:base:1.0"):
+        ElementTree.register_namespace(parse_namespace(mo.group("namespace")), mo.group("namespace"))
+
+    for element in xml_element:
+        sort(element)
+
+
+def diff_xml(xml1, xml2, xpath):
+    """
+    Resolves differences between two xml files.
+    :param xml1: input file left side (original)
+    :param xml2: input file right side (to compare with)
+    :param xpath: xpath of element to read. example:
+                  ./{urn:ietf:params:xml:ns:yang:ietf-interfaces}interfaces/{ \
+                  urn:ietf:params:xml:ns:yang:ietf-interfaces}interface[{ \
+                  urn:ietf:params:xml:ns:yang:ietf-interfaces}name='loop0']
+    :return: diff of input files
+    """
+    ElementTree.register_namespace("nc", "urn:ietf:params:xml:ns:netconf:base:1.0")
+    tmp1 = unicode_writer(NamedTemporaryFile('w'))
+    normalize_xml(tmp1, ElementTree.parse(xml1), xpath)
+
+    tmp2 = unicode_writer(NamedTemporaryFile('w'))
+    normalize_xml(tmp2, ElementTree.parse(xml2), xpath)
+
+    return subprocess.call(["diff", "-u", "-s", "-d", "--label", xml1, "--label", xml2, tmp1.name, tmp2.name])
+
+
+def normalize_xml(tmp, tree, xpath):
+    root = tree.getroot() if (xpath == "*") else tree.getroot().find(xPath)
+    sort(root)
+    xml_str = ElementTree.tostring(root, encoding="utf-8", method="xml")
+    tmp.write(xml_str.decode("utf-8"))
+    tmp.flush()
+    #   format and normalize output using xmllint
+    #   cmd: xmllint --exc-c14n [file_name] -o [file_name]
+    subprocess.call(["xmllint", "--format", tmp.name, "-o", tmp.name])
+
+
+if __name__ == '__main__':
+    args = sys.argv
+    prog = os.path.basename(args.pop(0))
+
+    if '-h' in args or '--help' in args:
+        print_usage(prog)
+        exit(0)
+
+    if len(args) < 2:
+        print_usage(prog)
+        exit(1)
+    args.reverse()
+    file1 = args.pop(-1)
+    file2 = args.pop(-1)
+    if len(args) > 2:
+        xPath = args.pop(-1)
+    else:
+        xPath = "*"
+
+    exit(diff_xml(file1, file2, xPath))