dns.js

const
http = require('http'),
xml2js = new (require('xml2js')).Parser(),
jsel = require('JSONSelect');

function doRequest(api_key, method, path, body, cb) {
  var req = http.request({
    auth: api_key,
    host: 'ns.zerigo.com',
    port: 80,
    path: path,
    method: method,
    headers: {
      'Content-Type': 'application/xml',
      'Content-Length': body ? body.length : 0
    }
  }, function(r) {
    var buf = "";
    r.on('data', function(chunk) {
      buf += chunk;
    });
    r.on('end', function() {
      if ((r.statusCode / 100).toFixed(0) != 2 &&
          r.statusCode != 404) {
        return cb("non 200 status: " + r.statusCode + "(" + body + ")");
      }
      xml2js.parseString(buf, cb);
    });
  });
  if (body) req.write(body);
  req.end();
};

exports.updateRecord = function (key, hostname, ip, cb) {
  if (typeof key !== 'string' || !hostname) return process.nextTick(function() { cb(null) });

  exports.deleteRecord(key, hostname, function(err) {
    if (err && err !== 'no such DNS record') return cb(err);

    doRequest(key, 'GET', '/api/1.1/zones.xml', null, function(err, r) {
      var host = "";
      if (err) return cb(err);
      var m = jsel.match('object:has(:root > .domain:val(?)) > .id .#',
                         [ hostname ], r);
      if (m.length != 1) {
        host = hostname.split('.')[0];
        hostname = hostname.split('.').slice(1).join('.');
        var m = jsel.match('object:has(:root > .domain:val(?)) > .id .#',
                           [ hostname ], r);
        if (m.length != 1) return cb("couldn't extract domain id from zerigo");      
      }

      var path = '/api/1.1/hosts.xml?zone_id=' + m[0];
      var body = '<host><data>' + ip + '</data><host-type>A</host-type>';
      body += '<hostname>' + host + '</hostname>'
      body += '</host>';
      doRequest(key, 'POST', path, body, function(err, r) {
        cb(err);
      });
    });
  });
};

exports.findByIP = function (key, ip, cb) {
  if (!key) return cb(null, null);

  doRequest(key, 'GET', '/api/1.1/zones.xml', null, function(err, r) {
    if (err) return cb(err);
    var zones = jsel.match('.id .#', r);

    if (!zones.length) return cb(null, []);
    
    var done = 0;
    var found = [];
    var failed;

    zones.forEach(function(zone) {
      doRequest(key, 'GET', '/api/1.1/zones/' + zone + '/hosts.xml?per_page=1000', null, function(err, r) {
        if (failed) return;
        if (err) {
          failed = err;
          return cb(err);
        }
        var m = jsel.match('object:has(:root > .data:val(?)) > .fqdn', [ ip ], r);
        found = found.concat(m);
        if (++done === zones.length) cb(null, found);
      });
    });
  });
};

exports.deleteRecord = function (key, hostname, cb) {
  doRequest(key, 'GET', '/api/1.1/hosts.xml?fqdn=' + hostname, null, function(err, r) {
    if (err) return cb(err);
    var m = jsel.match('.host .id > .#', r);
    if (!m.length) return cb("no such DNS record");
    function deleteOne() {
      if (!m.length) return cb(null);
      var one = m.shift();
      doRequest(key, 'DELETE', '/api/1.1/hosts/' + one + '.xml', null, function(err) {
        if (err) return cb(err);
        deleteOne();
      });
    }
    deleteOne();
  });
};

exports.inUse = function (key, hostname, cb) {
  if (!key || !hostname) return process.nextTick(function() { cb(null) });
  doRequest(key, 'GET', '/api/1.1/hosts.xml?fqdn=' + hostname, null, function(err, r) {
    if (err) return cb(err);
    var m = jsel.match('.host', r);
    // we shouldn't have multiple!  oops!  let's return the first one
    if (m.length) return cb(null, m[0]);
    cb(null, null);
  });
}