juniper.py

import contextlib
import json
import logging
import re

import paramiko

from inventory_provider.constants import JUNIPER_LOGGER_NAME


def neighbors(router, routing_instances=["IAS"], group_expression=None):

    for config in router["bgp"]["configuration"]:
        for ri in config["routing-instances"]:
            for inst in ri["instance"]:
                if inst["name"]["data"] not in routing_instances:
                    continue
                for prot in inst["protocols"]:
                    for bgp in prot.get("bgp", []):
                        for g in bgp.get("group", []):
                            if group_expression and not \
                                    re.match(group_expression, g["name"]["data"]):
                                continue
                            for n in g["neighbor"]:
                                yield n


def interfaces(router):
    for ifc_info in router["interfaces"]["interface-information"]:
        for ifc_list in ifc_info["logical-interface"]:
            for ifc in ifc_list:
                yield {
                    "name": ifc["name"][0]["data"],
                    "status": "%s/%s" % (
                        ifc["admin-status"][0]["data"],
                        ifc["oper-status"][0]["data"]),
                    "description": ifc["description"][0]["data"],
                    "type": "logical"
                }


@contextlib.contextmanager
def ssh_connection(router, ssh_params):
    import os
    key_filename = os.path.join(os.path.dirname(__file__), ssh_params["private-key"])
    known_hosts = os.path.join(os.path.dirname(__file__), ssh_params["known-hosts"])
    k = paramiko.DSSKey.from_private_key_file(key_filename)

    router["hostname"] = "mx1.ams.nl.geant.net"
    with paramiko.SSHClient() as ssh:
        ssh.load_host_keys(known_hosts)
        ssh.connect(
            hostname=router["hostname"],
            username="Monit0r",
            pkey=k)
        yield ssh


def exec_router_commands_json(router, ssh_params, commands):
    juniper_logger = logging.getLogger(JUNIPER_LOGGER_NAME)
    with ssh_connection(router, ssh_params) as ssh:

        _, stdout, _ = ssh.exec_command("set cli screen-length 0")
        assert stdout.channel.recv_exit_status() == 0

        def _dups_to_list(pairs):
            counter_map = {}
            for k, v in pairs:
                counter_map.setdefault(k, []).append(v)
            result = {}
            for k, v in counter_map.items():
                if len(v) == 1:
                    result[k] = v[0]
                else:
                    result[k] = v
            return result

        for c in commands:
            juniper_logger.debug("command: '%s'" % (c + " | display json"))
            _, stdout, _ = ssh.exec_command(c + " | display json")
            assert stdout.channel.recv_exit_status() == 0
            # TODO: error handling
            output = stdout.read()
            if output:
                juniper_logger.debug("%r output: [%d] %r" % (router, len(output), output[:20]))
                yield json.loads(output, object_pairs_hook=_dups_to_list)
            else:
                juniper_logger.debug("%r output empty" % router)
                yield {}