obtain ip address and gateways

"""
Example to obtain local ips and gateways with
iproute2 (called as subprocess) and netifaces (module)
which provides a generic api for all os.
"""


import json
from subprocess import check_output
from socket import AF_INET

from netifaces import gateways, interfaces, ifaddresses


def get_local_ips():
    cmd = ["ip", "-j", "-4", "a", "s", "scope", "global"]
    result = json.loads(check_output(cmd, encoding="utf8"))
    return [
        addr["local"] for res in result
        for addr in res.get("addr_info", [])
    ]


def get_default_gateways():
    cmd = ["ip", "-j", "-4", "r", "s", "default"]
    result = json.loads(check_output(cmd, encoding="utf8"))
    return [res.get("gateway", "") for res in result]


def get_local_ips2():
    ips = []
    for interface in interfaces():
        if interface == "lo":
            continue
        for result in ifaddresses(interface).get(AF_INET, []):
            ips.append(result["addr"])
    return ips


def get_default_gateways2():
    ips = []
    result = gateways().get("default", {}).get(AF_INET, ())
    return [result[0]]