text: /* Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved. */
  
  /******************************************************************************
   *
   * You may not use the identified files except in compliance with the Apache
   * License, Version 2.0 (the "License.")
   *
   * You may obtain a copy of the License at
   * http://www.apache.org/licenses/LICENSE-2.0.
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *
   * See the License for the specific language governing permissions and
   * limitations under the License.
   *
   * NAME
   *   connectionpool.js
   *
   * DESCRIPTION
   *   Shows connection pool usage.  Connection pools are recommended
   *   for applications that use a lot of connections for short periods.
   *
   *   Other connection pool examples are in sessionfixup.js and webappawait.js.
   *   For a standalone connection example, see connect.js
   *
   *   In some networks forced pool termination may hang unless you have
   *   'disable_oob=on' in sqlnet.ora, see
   *   https://oracle.github.io/node-oracledb/doc/api.html#tnsadmin
   *
   *   In production applications, set poolMin=poolMax (and poolIncrement=0)
   *
   *   This example uses Node 8's async/await syntax.
   *
   *****************************************************************************/
  
  // If you increase poolMax, you must increase UV_THREADPOOL_SIZE before Node.js
  // starts its thread pool.  If you set UV_THREADPOOL_SIZE too late, the value is
  // ignored and the default size of 4 is used.
  // process.env.UV_THREADPOOL_SIZE = 4;
  
  const oracledb = require('oracledb');
  const dbConfig = require('./dbconfig.js');
  
  async function init() {
    try {
      // Create a connection pool which will later be accessed via the
      // pool cache as the 'default' pool.
      await oracledb.createPool({
        user: dbConfig.user,
        password: dbConfig.password,
        connectString: dbConfig.connectString
        // edition: 'ORA$BASE', // used for Edition Based Redefintion
        // events: false, // whether to handle Oracle Database FAN and RLB events or support CQN
        // externalAuth: false, // whether connections should be established using External Authentication
        // homogeneous: true, // all connections in the pool have the same credentials
        // poolAlias: 'default', // set an alias to allow access to the pool via a name.
        // poolIncrement: 1, // only grow the pool by one connection at a time
        // poolMax: 4, // maximum size of the pool. Increase UV_THREADPOOL_SIZE if you increase poolMax
        // poolMin: 0, // start with no connections; let the pool shrink completely
        // poolPingInterval: 60, // check aliveness of connection if idle in the pool for 60 seconds
        // poolTimeout: 60, // terminate connections that are idle in the pool for 60 seconds
        // queueMax: 500, // don't allow more than 500 unsatisfied getConnection() calls in the pool queue
        // queueTimeout: 60000, // terminate getConnection() calls queued for longer than 60000 milliseconds
        // sessionCallback: myFunction, // function invoked for brand new connections or by a connection tag mismatch
        // stmtCacheSize: 30, // number of statements that are cached in the statement cache of each connection
        // _enableStats: false // record pool usage statistics that can be output with pool._logStats()
      });
      console.log('Connection pool started');
  
      // Now the pool is running, it can be used
      await dostuff();
  
    } catch (err) {
      console.error('init() error: ' + err.message);
    } finally {
      await closePoolAndExit();
    }
  }
  
  async function dostuff() {
    let connection;
    try {
      // Get a connection from the default pool
      connection = await oracledb.getConnection();
      const sql = `SELECT sysdate FROM dual WHERE :b = 1`;
      const binds = [1];
      const options = { outFormat: oracledb.OUT_FORMAT_OBJECT };
      const result = await connection.execute(sql, binds, options);
      console.log(result);
      // oracledb.getPool()._logStats(); // show pool statistics.  _enableStats must be true
    } catch (err) {
      console.error(err);
    } finally {
      if (connection) {
        try {
          // Put the connection back in the pool
          await connection.close();
        } catch (err) {
          console.error(err);
        }
      }
    }
  }
  
  async function closePoolAndExit() {
    console.log('\nTerminating');
    try {
      // Get the pool from the pool cache and close it when no
      // connections are in use, or force it closed after 10 seconds.
      // If this hangs, you may need DISABLE_OOB=ON in a sqlnet.ora file.
      // This setting should not be needed if both Oracle Client and Oracle
      // Database are 19c (or later).
      await oracledb.getPool().close(10);
      console.log('Pool closed');
      process.exit(0);
    } catch(err) {
      console.error(err.message);
      process.exit(1);
    }
  }
  
  process
    .once('SIGTERM', closePoolAndExit)
    .once('SIGINT',  closePoolAndExit);
  
  init();
  