lib/instrumentation/modules/bluebird.js

/*
 * Copyright Elasticsearch B.V. and other contributors where applicable.
 * Licensed under the BSD 2-Clause License; you may not use this file except in
 * compliance with the BSD 2-Clause License.
 */

'use strict';

var semver = require('semver');

var shimmer = require('../shimmer');

var massWrap = shimmer.massWrap;
var wrap = shimmer.wrap;

var BLUEBIRD_FNS = ['_then', '_addCallbacks'];

module.exports = function (bluebird, agent, { version }) {
  var ins = agent._instrumentation;

  if (!semver.satisfies(version, '>=2 <4')) {
    agent.logger.debug(
      'bluebird version %s not supported - aborting...',
      version,
    );
    return bluebird;
  }

  agent.logger.debug('shimming bluebird.prototype functions: %j', BLUEBIRD_FNS);
  massWrap(bluebird.prototype, BLUEBIRD_FNS, wrapThen);

  // Calling bluebird.config might overwrite the
  // bluebird.prototype._attachCancellationCallback function with a new
  // function. We need to hook into this new function
  agent.logger.debug('shimming bluebird.config');
  wrap(bluebird, 'config', function wrapConfig(original) {
    return function wrappedConfig() {
      var result = original.apply(this, arguments);

      agent.logger.debug(
        'shimming bluebird.prototype._attachCancellationCallback',
      );
      wrap(
        bluebird.prototype,
        '_attachCancellationCallback',
        function wrapAttachCancellationCallback(original) {
          return function wrappedAttachCancellationCallback(onCancel) {
            if (arguments.length !== 1) return original.apply(this, arguments);
            return original.call(this, ins.bindFunction(onCancel));
          };
        },
      );

      return result;
    };
  });

  // WARNING: even if you remove these two shims, the tests might still pass
  // for bluebird@2. The tests are flaky and will only fail sometimes and in
  // some cases only if run together with the other tests.
  //
  // To test, run in a while-loop:
  //
  //   while :; do node test/instrumentation/modules/bluebird/bluebird.js || exit $?; done
  if (semver.satisfies(version, '<3')) {
    agent.logger.debug('shimming bluebird.each');
    wrap(bluebird, 'each', function wrapEach(original) {
      return function wrappedEach(promises, fn) {
        if (arguments.length !== 2) return original.apply(this, arguments);
        return original.call(this, promises, ins.bindFunction(fn));
      };
    });

    agent.logger.debug('shimming bluebird.prototype.each');
    wrap(bluebird.prototype, 'each', function wrapEach(original) {
      return function wrappedEach(fn) {
        if (arguments.length !== 1) return original.apply(this, arguments);
        return original.call(this, ins.bindFunction(fn));
      };
    });
  }

  return bluebird;

  function wrapThen(original) {
    return function wrappedThen() {
      var args = Array.prototype.slice.call(arguments);
      if (typeof args[0] === 'function') args[0] = ins.bindFunction(args[0]);
      if (typeof args[1] === 'function') args[1] = ins.bindFunction(args[1]);
      return original.apply(this, args);
    };
  }
};