"use strict"; const net = require("net"); const execa = require("execa"); const dests = ["default", "0.0.0.0", "0.0.0.0/0", "::", "::/0"]; const args = { v4: ["-rn", "-f", "inet"], v6: ["-rn", "-f", "inet6"], }; const parse = (stdout, family) => { let result; (stdout || "").trim().split("\n").some(line => { const results = line.split(/ +/) || []; const target = results[0]; const gateway = results[1]; const iface = results[family === "v4" ? 5 : 3]; if (dests.includes(target) && gateway && net.isIP(gateway)) { result = {gateway, interface: (iface ? iface : null)}; return true; } }); if (!result) { throw new Error("Unable to determine default gateway"); } return result; }; const promise = family => { return execa.stdout("netstat", args[family]).then(stdout => { return parse(stdout, family); }); }; const sync = family => { const result = execa.sync("netstat", args[family]); return parse(result.stdout, family); }; module.exports.v4 = () => promise("v4"); module.exports.v6 = () => promise("v6"); module.exports.v4.sync = () => sync("v4"); module.exports.v6.sync = () => sync("v6");