How to iterate to the ipv4 address NETCONF XML - Devnet course

[_|brt.drml|_]

Hi there

I'm trying to create a script after relentless hours of study :-)

I just need to know how to iterate through the xml data and 'print' out the requested IPV4 address

This is the script:

[all information is more then welcome: the 'output print to a txt' file is here not finished.] just got stuck in the basics

#!/usr/bin/env python

# the imports are modules that need to be installed on your system! If not the script will fail!

import json

import os

import sys

import time

import threading

from ncclient import manager

import xmltodict

import xml.dom.minidom

from pprint import pprint

# Get the absolute path for the directory where this file is located "here"

here = os.path.abspath(os.path.dirname(__file__))

# Get the absolute path for the project / repository root

project_root = os.path.abspath(os.path.join(here, "../.."))

# Extend the system path to include the 'connecting device' in the root and import the env files -> the username pwd etc.

sys.path.insert(0, project_root)

import env_lab

# Create an XML filter for targeted NETCONF queries -> XML filters the requested output -> this is the data model that is needed to talk to the IOS Xe

netconf_filter = """

<filter>

  <interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">

    <interface></interface>

  </interfaces>

</filter>"""

print("Opening NETCONF Connection to {}".format(env_lab.EoIP["host"]))

# Open a connection to the network device using ncclient

with manager.connect(

        host=env_lab.EoIP["host"],

        port=env_lab.EoIP["netconf_port"],

        username=env_lab.EoIP["username"],

        password=env_lab.EoIP["password"],

        hostkey_verify=False

        ) as m:

    print("Sending a <get-config> operation to the device.\n")

    # Make a NETCONF <get-config> query using the filter

    netconf_reply = m.get_config(source = 'running', filter = netconf_filter)

print("Here is the raw XML data returned from the device.\n")

# Print out the raw XML that returned

print(xml.dom.minidom.parseString(netconf_reply.xml).toprettyxml())

print("")

# Parse the returned XML to an Ordered Dictionary -> to get the data out of it.

netconf_data = xmltodict.parse(netconf_reply.xml)

interfaces = netconf_data["rpc-reply"]["data"]["interfaces"]["interface"]

print(interfaces)

print("")

# Create a list of interfaces

for interface in interfaces:

    print("Interface : {name} : ip : {ip} : netmask : {mask} : Status : {status} : ".format(

            name = interface["name"],

            ip = interface["ipv4"]["address"]["ip"],

            mask = interface["ipv4"]["address"]["netmask"],

            status  = interface["enabled"]

            )

        )

print("\n")

host=env_lab.EoIP["host"]

username=env_lab.EoIP["username"]

#sleep for a while - so windows can follow !

time.sleep(1)

print("generating the outputfile of {}".format(host))

time.sleep(0.75)

print("The file is created by user: {}".format(username))

time.sleep(0.75)

print("The file is generated at location: {}".format(here))

time.sleep(0.75)

# Parse the entire folder to make ready for printing out

output_xml = xml.dom.minidom.parseString(netconf_reply.xml).toprettyxml()

with open("{}.txt".format(host), "w") as file:

    file.write(output_xml)

[omz · Accepted solution]

Hi 

Whats the issue? Is it the key error?

Interface : GigabitEthernet1 : ip : 10.10.20.48 : netmask : 255.255.255.0 : Status : true :
Interface : GigabitEthernet2 : ip : 10.255.255.1 : netmask : 255.255.255.0 : Status : true :
Traceback (most recent call last):
  File "test.py", line 57, in <module>
    ip = interface["ipv4"]["address"]["ip"],
KeyError: 'address'

 If the issue is the key error - its because the interface doesn't have an address configured.

You can use a try-except block to catch the key error.

Something like this may work - 

# Create a list of interfaces
for interface in interfaces:
    try:
        print("Interface : {name} : ip : {ip} : netmask : {mask} : Status : {status} : ".format(
            name = interface["name"],
            ip = interface["ipv4"]["address"]["ip"],
            mask = interface["ipv4"]["address"]["netmask"],
            status  = interface["enabled"]
            )
        )
    except KeyError:
        print("Interface : {name} : Status : {status} : ".format(
            name = interface["name"],
            status  = interface["enabled"]
            )
        )

[_|brt.drml|_]

Okay, this was the solution.

I guess this is the same issue with processing via ElementTree. With that I could generate the entire 'xml' block as a list. But I could not get results with the find or findall ...

I would have hoped that an "empty" value would be 'visible'.



Well I certainly learned something.



Thank you for this response. I hope it would help for others to come!