source: trip-planner-front/node_modules/internal-ip/index.js@ 76712b2

'use strict';
const os = require('os');
const defaultGateway = require('default-gateway');
const ipaddr = require('ipaddr.js');

function findIp(gateway) {
        const interfaces = os.networkInterfaces();
        const gatewayIp = ipaddr.parse(gateway);
        let ip;

        // Look for the matching interface in all local interfaces
        Object.keys(interfaces).some(name => {
                return interfaces[name].some(addr => {
                        const prefix = ipaddr.parse(addr.netmask).prefixLengthFromSubnetMask();
                        const net = ipaddr.parseCIDR(`${addr.address}/${prefix}`);

                        if (net[0] && net[0].kind() === gatewayIp.kind() && gatewayIp.match(net)) {
                                ip = net[0].toString();
                        }

                        return Boolean(ip);
                });
        });

        return ip;
}

function promise(family) {
        return defaultGateway[family]().then(result => {
                return findIp(result.gateway) || null;
        }).catch(() => null);
}

function sync(family) {
        try {
                const result = defaultGateway[family].sync();
                return findIp(result.gateway) || null;
        } catch (error) {
                return null;
        }
}

const internalIp = {};
internalIp.v6 = () => promise('v6');
internalIp.v4 = () => promise('v4');
internalIp.v6.sync = () => sync('v6');
internalIp.v4.sync = () => sync('v4');

module.exports = internalIp;
// TODO: Remove this for the next major release
module.exports.default = internalIp;