ApplyEventsFromDbStream.js

/**
 * @license
 * Copyright (C) 2020–2025 Pryv S.A. https://pryv.com
 *
 * This file is part of Open-Pryv.io and released under BSD-Clause-3 License
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors
 *   may be used to endorse or promote products derived from this software
 *   without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */
const Transform = require('stream').Transform;
const inherits = require('util').inherits;
const converters = require('./converters');

module.exports = ApplyEventsFromDbStream;

inherits(ApplyEventsFromDbStream, Transform);

/**
 * @param {Array<Function>} convs
 */
function ApplyEventsFromDbStream (itemFromDBConverters) {
  Transform.call(this, { objectMode: true });
  this.trans = converters.getRenamePropertyFn('_id', 'id');
  this.converters = itemFromDBConverters;
}

ApplyEventsFromDbStream.prototype._transform = function (event, encoding, callback) {
  try {
    event = this.trans(event);
    // SingleCollectionsMode - start
    delete event.userId;

    for (const converter of this.converters) {
      event = converter(event);
    }

    this.push(event);
    callback();
  } catch (err) {
    return callback(err);
  }
};