fcoin/lib/net/dns.js
Christopher Jeffrey cdbad54a8c
net: improvements. see comments.
- Improved local address handling.
- Enabled upnp discovery.
- Added retry for dns seeds.
- Improved hostlist in general.
2017-03-07 17:10:47 -08:00

85 lines
1.5 KiB
JavaScript

/*!
* dns.js - dns backend for bcoin
* Copyright (c) 2014-2017, Christopher Jeffrey (MIT License).
* https://github.com/bcoin-org/bcoin
*/
'use strict';
/**
* @module net/dns
*/
var dns = require('dns');
var socks = require('./socks');
var options = {
family: 4,
hints: dns.ADDRCONFIG | dns.V4MAPPED,
all: true
};
/**
* Resolve host (no getaddrinfo).
* @param {String} host
* @param {String?} proxy - Tor socks proxy.
* @returns {Promise}
*/
exports.resolve = function resolve(host, proxy) {
if (proxy)
return socks.resolve(proxy, host);
return new Promise(function(resolve, reject) {
dns.resolve(host, 'A', function(err, result) {
if (err) {
reject(err);
return;
}
if (result.length === 0) {
reject(new Error('No DNS results.'));
return;
}
resolve(result);
});
});
};
/**
* Resolve host (getaddrinfo).
* @param {String} host
* @param {String?} proxy - Tor socks proxy.
* @returns {Promise}
*/
exports.lookup = function lookup(host, proxy) {
if (proxy)
return socks.resolve(proxy, host);
return new Promise(function(resolve, reject) {
var addrs = [];
var i, addr;
dns.lookup(host, options, function(err, result) {
if (err) {
reject(err);
return;
}
if (result.length === 0) {
reject(new Error('No DNS results.'));
return;
}
for (i = 0; i < result.length; i++) {
addr = result[i];
addrs.push(addr.address);
}
resolve(addrs);
});
});
};