sequelize/lib/dialects/db2/connection-manager.js

Sequelize is a promise-based Node.js ORM tool for Postgres, MySQL, MariaDB, SQLite, Microsoft SQL Server, Amazon Redshift and Snowflake’s Data Cloud. It features solid transaction support, relations, eager and lazy loading, read replication and more.

'use strict';

const AbstractConnectionManager = require('../abstract/connection-manager');
const sequelizeErrors = require('../../errors');
const { logger } = require('../../utils/logger');
const DataTypes = require('../../data-types').db2;
const debug = logger.debugContext('connection:db2');
const parserStore = require('../parserStore')('db2');

/**
 * DB2 Connection Manager
 *
 * Get connections, validate and disconnect them.
 * AbstractConnectionManager pooling use it to handle DB2 specific connections
 * Use https://github.com/ibmdb/node-ibm_db to connect with DB2 server
 *
 * @private
 */
class ConnectionManager extends AbstractConnectionManager {
  constructor(dialect, sequelize) {
    sequelize.config.port = sequelize.config.port || 3306;
    super(dialect, sequelize);
    this.lib = this._loadDialectModule('ibm_db');
    this.refreshTypeParser(DataTypes);
  }

  static _typecast(field, next) {
    if (parserStore.get(field.type)) {
      return parserStore.get(field.type)(field, this.sequelize.options, next);
    }
    return next();
  }

  _refreshTypeParser(dataType) {
    parserStore.refresh(dataType);
  }

  _clearTypeParser() {
    parserStore.clear();
  }

  /**
   * Connect with DB2 database based on config, Handle any errors in connection
   * Set the pool handlers on connection.error
   * Also set proper timezone once connection is connected.
   *
   * @param {object} config
   * @returns {Promise<Connection>}
   * @private
   */
  async connect(config) {
    const connectionConfig = {
      database: config.database,
      hostname: config.host,
      port: config.port,
      uid: config.username,
      pwd: config.password
    };

    if (config.ssl) {
      connectionConfig['security'] = config.ssl;
    }
    if (config.sslcertificate) {
      connectionConfig['SSLServerCertificate'] = config.sslcertificate;
    }
    if (config.dialectOptions) {
      for (const key of Object.keys(config.dialectOptions)) {
        connectionConfig[key] = config.dialectOptions[key];
      }
    }

    try {
      const connection = await new Promise((resolve, reject) => {
        const connection = new this.lib.Database();
        connection.lib = this.lib;
        connection.open(connectionConfig, error => {
          if (error) {
            if (error.message && error.message.includes('SQL30081N')) {
              return reject(new sequelizeErrors.ConnectionRefusedError(error));
            }
            return reject(new sequelizeErrors.ConnectionError(error));
          }
          return resolve(connection);
        });
      });
      return connection;
    } catch (err) {
      throw new sequelizeErrors.ConnectionError(err);
    }
  }

  disconnect(connection) {
    // Don't disconnect a connection that is already disconnected
    if (connection.connected) {
      connection.close(error => {
        if (error) { debug(error); }
        else { debug('connection closed'); }
      });
    }
    return Promise.resolve();
  }

  validate(connection) {
    return connection && connection.connected;
  }

  /**
   * Call dialect library to disconnect a connection
   *
   * @param {Connection} connection
   * @private
   * @returns {Promise}
   */
  _disconnect(connection) {
    return this.dialect.connectionManager.disconnect(connection);
  }
}

module.exports = ConnectionManager;
module.exports.ConnectionManager = ConnectionManager;
module.exports.default = ConnectionManager;