Function getMetadataServiceInfo

lib/datastax/cloud/index.js:145–203

* Gets the information retrieved from the metadata service. * Invokes the callback with {proxyAddress, localDataCenter, contactPoints} as result * @param {CloudOptions} cloudOptions * @param {Function} callback

(cloudOptions, callback)

 * @param {Function} callback
 */
function getMetadataServiceInfo(cloudOptions, callback) {
  const regex = /^(.+?):(\d+)(.*)$/;
  const matches = regex.exec(cloudOptions.serviceUrl);
  callback = utils.callbackOnce(callback);

  if (!matches || matches.length !== 4) {
    throw new TypeError('url should be composed of host, port number and path, without scheme');
  }

  const requestOptions = Object.assign({
    hostname: matches[1],
    port: matches[2],
    path: matches[3] || undefined,
    timeout: cloudOptions.clientOptions.socketOptions.connectTimeout
  }, cloudOptions.clientOptions.sslOptions);

  const req = https.get(requestOptions, res => {
    let data = '';

    utils.log('verbose', `Connected to metadata service with SSL/TLS protocol ${res.socket.getProtocol()}`, {}, cloudOptions);

    res
      .on('data', chunk => data += chunk.toString())
      .on('end', () => {
        if (res.statusCode !== 200) {
          return callback(getServiceRequestError(new Error(`Obtained http status ${res.statusCode}`), requestOptions));
        }

        let message;

        try {
          message = JSON.parse(data);

          if (!message || !message['contact_info']) {
            throw new TypeError('contact_info should be defined in response');
          }

        } catch (err) {
          return callback(getServiceRequestError(err, requestOptions, true));
        }

        const contactInfo = message['contact_info'];

        // Set the connect options
        cloudOptions.clientOptions.contactPoints = contactInfo['contact_points'];
        cloudOptions.clientOptions.localDataCenter = contactInfo['local_dc'];
        cloudOptions.clientOptions.sni = { address: contactInfo['sni_proxy_address'] };

        callback();
      });
  });

  req.on('error', err => callback(getServiceRequestError(err, requestOptions)));

  // We need to both set the timeout in the requestOptions and invoke ClientRequest#setTimeout()
  // to handle all possible scenarios, for some reason... (tested with one OR the other and didn't fully work)
  // Setting the also the timeout handler, aborting will emit 'error' and close
  req.setTimeout(cloudOptions.clientOptions.socketOptions.connectTimeout, () => req.abort());