index.js

const { MongoClient } = require('mongodb');

module.exports = (options) => {
  const MongoClientInstance = options && options.MongoClient ? options.MongoClient : MongoClient;
  let client;
  let config;
  let logger;

  const start = async (dependencies) => {
    config = { ...dependencies.config };
    logger = ({ ...dependencies.logger }) || console;

    if (!dependencies.logger) {
      logger.info = console.log;
    }

    if (!config || !config.url) {
      throw new Error('config.url is required');
    }

    if (!config.options) {
      config.options = {};
    }

    const mongoOptions = { ...config.options };

    if( config.showConnectionString ){
      logger.info(`Connecting to ${config.url}`);
    }else{
      logger.info(`Connecting to server <hidden connection url>`);
    }

    try {
      client = await MongoClientInstance.connect(config.url, mongoOptions );

      return client;
    } catch (error) {
      throw new Error(error);
    }
  };

  const stop = async () => {
    if (!client) {
      logger.info('No database has been opened.');
      return;
    }

    if (config.showConnectionString) {
      logger.info(`Disconnecting from ${config.url}`);
    } else {
      logger.info(`Disconnecting from server <hidden connection url>`);
    }
    await client.close();
  };

  return {
    start,
    stop,
  };
};