deep-framework/vendor/aws-xray-sdk/lib/patchers/http_p.js

DEEP Framework

/**
 * @module http_p
 */

var _ = require('underscore');

var CLSUtils = require('../utils').CLSUtils;

var getCauseType = require('../utils').getCauseTypeFromHttpStatus;
var logger = require('../logger');

/**
 * Wraps the http/https.request() call to automatically capture information for the segment.
 * @param {http|https} module - The built in Node.js HTTP or HTTPS module.
 * @alias module:http_p.captureHTTPs
 * @returns {http|https}
 */

var captureHTTPs = function captureHTTPs(module) {
  if (module.__request)
    return module;

  module.__request = module.request;

  module.request = function captureHTTPsRequest(options, callback) {
    if (!options || (options.headers && (options.headers['X-Amzn-Trace-Id'] || options.headers['X-Amz-Date']))) {
      return module.__request(options, callback);
    } else if (_.isUndefined(options.Segment) && !CLSUtils.isCLSMode()) {
      logger.info('Options for request ' + options + ' requires a Segment param for manual mode.');
      return module.__request(options, callback);
    }

    var parent = options.Segment ? options.Segment : CLSUtils.getSegment();
    var hostname = options.hostname || options.host || 'Unknown host';

    if (_.isUndefined(parent)) {
      logger.info('Options for request [ host:' + hostname + ', method:' + options.method + ', path:' +
        options.path + ']  requires a Segment param for manual mode.');
      return module.__request(options, callback);
    }

    var root = parent.segment ? parent.segment : parent;
    var traced = root.notTraced ? false : true;

    var subsegment = parent.addNewSubsegment(hostname);
    subsegment.addRemote();

    var req = module.__request(_.omit(options, 'Segment'), function(res) {
      res.on('end', function() {
        subsegment.addRemoteData(res.req, res, traced);
        subsegment.close();
      });

      if (typeof callback === 'function') {
        if (CLSUtils.isCLSMode()) {
          var session = CLSUtils.getNamespace();

          session.run(function() {
            CLSUtils.setSegment(subsegment);
            callback(res);
          });
        } else {
          callback(res);
        }
      }
    });

    var errorCapturer = function (e) {
      if (subsegment.http) {
        subsegment.close(e, getCauseType(subsegment.http.response.status), true);
      } else {
        subsegment.addRemoteData(req, null, traced);
        subsegment.close(e);
      }

      if (req._events && req._events.error && req._events.error.length === 1) {
        req.removeListener('error', errorCapturer);
        req.emit('error', e);
      }
    };

    req.on('error', errorCapturer);

    req.setHeader('X-Amzn-Trace-Id', 'Root=' + root['trace_id'] + '; Parent=' + subsegment.id +
      '; Sampled=' + (traced ? '1' : '0'));

    return req;
  };
};

module.exports.captureHTTPs = captureHTTPs;