//  SPDX-License-Identifier: LGPL-2.1-or-later
//  Copyright (c) 2015-2024 MariaDB Corporation Ab

'use strict';

const base = require('../base.js');
const { assert } = require('chai');
const Collations = require('../../lib/const/collations.js');
const Conf = require('../conf');
const Connection = require('../../lib/connection');
const ConnOptions = require('../../lib/config/connection-options');
const Net = require('net');
const { isMaxscale } = require('../base');
const dns = require('dns');

describe('connection', () => {
  it('with no connection attributes', function (done) {
    connectWithAttributes(false, done);
  });

  it('with basic connection attributes', function (done) {
    connectWithAttributes(true, done);
  });

  it('with basic connection attributes non node.js encoding', function (done) {
    connectWithAttributes(true, done, 'big5');
  });

  it('with small connection attributes', function (done) {
    connectWithAttributes({ par1: 'bouh', par2: 'bla' }, done);
  });

  it('with medium connection attributes', function (done) {
    const mediumAttribute = Buffer.alloc(512, 'a').toString();
    connectWithAttributes({ par1: 'bouh', par2: mediumAttribute }, done);
  });

  function connectWithAttributes(attr, done, charset) {
    base
      .createConnection({ connectAttributes: attr, charset: charset })
      .then((conn) => {
        conn
          .query("SELECT '1' as '1'")
          .then((rows) => {
            assert.deepEqual(rows, [{ 1: '1' }]);
            assert.equal(rows.meta[0].name(), '1');
            assert.equal(rows.meta[0].orgName(), '');
            conn.end();
            done();
          })
          .catch(done);
      })
      .catch(done);
  }

  it('connection attributes with encoding not supported by node.js', function (done) {
    const mediumAttribute = Buffer.alloc(500, 'a').toString();
    base
      .createConnection({
        connectAttributes: { par1: 'bouh', par2: mediumAttribute },
        collation: 'BIG5_CHINESE_CI'
      })
      .then((conn) => {
        conn
          .query("SELECT '1'")
          .then((rows) => {
            assert.deepEqual(rows, [{ 1: '1' }]);
            conn.end();
            done();
          })
          .catch(done);
      })
      .catch(done);
  });

  it('multiple connection.connect() with callback', function (done) {
    const conn = base.createCallbackConnection();
    assert.equal(-1, conn.threadId);

    conn.connect((err) => {
      if (err) done(err);
      assert.notEqual(-1, conn.threadId);
      //ensure double connect execute callback immediately
      conn.connect((err) => {
        if (err) done(err);
        conn.end(() => {
          conn.connect((err) => {
            //normal error
            assert.isTrue(err.message.includes('Connection closed'));
            assert.equal(err.sqlState, '08S01');
            assert.equal(err.code, 'ER_CONNECTION_ALREADY_CLOSED');
            done();
          });
        });
      });
    });
  });

  it('callback without connect', function (done) {
    const conn = base.createCallbackConnection();
    conn.query("select '1'", (err, rows) => {
      if (err) {
        done(err);
      } else {
        assert.deepEqual(rows, [{ 1: '1' }]);
        conn.end();
        done();
      }
    });
  });

  it('callback with connection error', function (done) {
    const conn = base.createCallbackConnection({
      connectTimeout: 200,
      socketTimeout: 200
    });
    conn.connect((err) => {
      if (!err) done(new Error('must have throw an error!'));
      assert.isTrue(err.message.includes('close forced'));
      done();
    });
    process.nextTick(conn.__tests.getSocket().destroy.bind(conn.__tests.getSocket(), new Error('close forced')));
  });

  it('callback with socket failing without error', function (done) {
    const conn = base.createCallbackConnection({ connectTimeout: 100 });
    conn.connect((err) => {
      if (!err) done(new Error('must have throw an error!'));
      assert.isTrue(err.message.includes('Connection timeout: failed to create socket after'));
      done();
    });
    process.nextTick(conn.__tests.getSocket().destroy.bind(conn.__tests.getSocket()));
  });

  it('socket timeout', function (done) {
    let conn;
    base
      .createConnection({ socketTimeout: 100, connectTimeout: null })
      .then((con) => {
        conn = con;
        return conn.query('SELECT SLEEP(1)');
      })
      .then(() => {
        done(new Error('must have thrown error !'));
      })
      .catch((err) => {
        assert.isTrue(err.message.includes('socket timeout'));
        assert.equal(err.sqlState, '08S01');
        assert.equal(err.errno, 45026);
        assert.equal(err.code, 'ER_SOCKET_TIMEOUT');
        done();
      });
  });

  it('connection.connect() callback mode without callback', function (done) {
    const conn = base.createCallbackConnection();
    try {
      conn.connect();
    } catch (err) {
      assert.isTrue(err.message.includes('missing mandatory callback parameter'));
      assert.equal(err.sqlState, 'HY000');
      assert.equal(err.errno, 45016);
      assert.equal(err.code, 'ER_MISSING_PARAMETER');
    }
    setTimeout(() => {
      conn.end();
      done();
    }, 500);
  });

  it('multiple connection.connect() with callback no function', function (done) {
    const conn = base.createCallbackConnection();
    conn.connect((err) => {});
    conn.connect((err) => {});
    conn.end(() => {
      conn.connect((err) => {});
      done();
    });
  });

  it('connection.connect() promise success parameter', function (done) {
    base
      .createConnection()
      .then((conn) => {
        return conn.end();
      })
      .then(() => {
        done();
      })
      .catch(done);
  });

  it('connection error event', function (done) {
    if (isMaxscale()) this.skip();
    if (!shareConn.info.isMariaDB() && !shareConn.info.hasMinVersion(5, 6, 0)) this.skip();
    base
      .createConnection()
      .then((conn) => {
        assert.equal(0, conn.listeners('error').length);
        conn.on('error', (err) => {
          done();
        });
        conn.query('KILL ' + conn.threadId).catch((err) => {
          assert.isTrue(
            err.message.includes('Connection was killed') || err.message.includes('Query execution was interrupted')
          );
          assert.equal(err.sqlState, '70100');
          assert.isTrue(err.errno === 1927 || err.errno === 1317);
        });
      })
      .catch(done);
  });

  it('connection error event socket failed', function (done) {
    base
      .createConnection({ socketTimeout: 100 })
      .then((conn) => {
        conn.on('error', (err) => {
          assert.isTrue(err.message.includes('socket timeout'));
          assert.equal(err.fatal, true);
          assert.equal(err.sqlState, '08S01');
          assert.equal(err.errno, 45026);
          assert.equal(err.code, 'ER_SOCKET_TIMEOUT');
          done();
        });
      })
      .catch(done);
  });

  it('multiple connection end with promise', function (done) {
    let conn;
    base
      .createConnection({
        logger: {
          error: (msg) => {}
        }
      })
      .then((con) => {
        conn = con;
        return conn.end();
      })
      .then(() => {
        return conn.end();
      })
      .then(() => {
        done();
      })
      .catch(done);
  });

  it('connection.connect() and query no waiting', function (done) {
    base
      .createConnection()
      .then((conn) => {
        conn
          .query("SELECT '1'")
          .then((rows) => {
            assert.deepEqual(rows, [{ 1: '1' }]);
            conn.end();
            done();
          })
          .catch(done);
      })
      .catch(done);
  });

  it('connection.ping()', async () => {
    const conn = await base.createConnection();
    conn.ping();
    await conn.ping();
    try {
      await conn.ping(-2);
      throw new Error('must have thrown error');
    } catch (err) {
      assert.isTrue(err.message.includes('Ping cannot have negative timeout value'));
    }
    await conn.ping(200);

    conn.query('SELECT SLEEP(1)');
    const initTime = Date.now();

    try {
      await conn.ping(200);
      throw new Error('must have thrown error after ' + (Date.now() - initTime));
    } catch (err) {
      assert.isTrue(
        Date.now() - initTime > 195,
        'expected > 195, without waiting for SLEEP to finish, but was ' + (Date.now() - initTime)
      );
      assert.isTrue(err.message.includes('Ping timeout'));
      assert.isFalse(conn.isValid());
    }
  });

  it('connection.ping() with callback', function (done) {
    const conn = base.createCallbackConnection();
    conn.connect((err) => {
      assert.equal(0, conn.listeners('error').length);
      conn.ping();
      conn.ping((err) => {
        if (err) {
          done(err);
        } else {
          conn.ping(-2, (err) => {
            if (!err) {
              done(new Error('must have thrown error'));
            } else {
              assert.isTrue(err.message.includes('Ping cannot have negative timeout value'));
              conn.ping(200, (err) => {
                if (err) {
                  done(err);
                } else {
                  conn.query('SELECT SLEEP(1)');
                  const initTime = Date.now();
                  conn.ping(200, (err) => {
                    if (!err) {
                      done(new Error('must have thrown error'));
                    } else {
                      assert.isTrue(
                        Date.now() - initTime > 195,
                        'expected > 195, without waiting for SLEEP to finish, but was ' + (Date.now() - initTime)
                      );
                      assert.isTrue(err.message.includes('Ping timeout'));
                      assert.isFalse(conn.isValid());
                      done();
                    }
                  });
                }
              });
            }
          });
        }
      });
    });
  });

  it('threadId access compatibility', function (done) {
    assert.isDefined(shareConn.threadId);
    assert.isTrue(shareConn.threadId !== -1);
    done();
  });

  it('connection.end() callback', function (done) {
    const conn = base.createCallbackConnection();
    conn.connect(function (err) {
      if (err) return done(err);
      conn.end(function () {
        done();
      });
    });
  });

  it('connection.end() promise', function (done) {
    base
      .createConnection()
      .then((conn) => {
        conn
          .end()
          .then(() => {
            done();
          })
          .catch(done);
      })
      .catch(done);
  });

  it('connection.destroy()', function (done) {
    this.timeout(10000);
    base
      .createConnection()
      .then((conn) => {
        conn.destroy();
        done();
      })
      .catch(done);
  });

  it('connection.destroy() when executing', function (done) {
    this.timeout(10000);
    base
      .createConnection()
      .then((conn) => {
        conn.query('SELECT 1');
        conn.destroy();
        done();
      })
      .catch(done);
  });

  it('connection.close alias', function (done) {
    this.timeout(10000);
    base
      .createConnection({ keepAliveDelay: 100 })
      .then((conn) => {
        conn.close();
        done();
      })
      .catch(done);
  });

  it('connection.destroy() during query execution', function (done) {
    if (isMaxscale()) this.skip();

    this.timeout(10000);

    base.createConnection().then((conn) => {
      //launch very long query
      conn
        .query(
          'select c1.* from information_schema.columns as c1,  information_schema.tables, information_schema.tables as t2'
        )
        .then(() => done(new Error('expected error !')))
        .catch((err) => {
          assert.isTrue(err != null);
          assert.isTrue(err.message.includes('Connection destroyed, command was killed'));
          assert.isTrue(err.fatal);
          done();
        });
      setTimeout(() => {
        conn.destroy();
      }, 10);
    });
  });

  it('connection timeout connect (wrong url) with callback', (done) => {
    const initTime = Date.now();
    dns.resolve4('www.google.com', (err, res) => {
      if (err) done();
      else if (res.length > 0) {
        const host = res[0];
        const conn = base.createCallbackConnection({
          host: host,
          connectTimeout: 1000
        });
        conn.connect((err) => {
          if (err.code !== 'ER_CONNECTION_TIMEOUT' && err.code !== 'ETIMEDOUT') {
            if (err.code === 'ENOTFOUND' || err.code === 'ENETUNREACH') {
              // if no network access or IP¨v6 not allowed, just skip error
              done();
              return;
            }
            console.log(err);
          }
          if (err.code === 'ER_CONNECTION_TIMEOUT') {
            assert.isTrue(err.message.includes('Connection timeout: failed to create socket after'));
          }
          assert.isTrue(Date.now() - initTime >= 990, 'expected > 990, but was ' + (Date.now() - initTime));
          assert.isTrue(Date.now() - initTime < 2000, 'expected < 2000, but was ' + (Date.now() - initTime));
          done();
        });
      } else done(new Error('DNS fails'));
    });
  });

  it('stream basic test', async function () {
    const conn = await base.createConnection({
      stream: (cb) => {
        cb(null, new Net.connect(Conf.baseConfig.port, Conf.baseConfig.host));
      }
    });
    conn.end();

    const conn2 = await base.createConnection({
      stream: () => {
        return new Net.connect(Conf.baseConfig.port, Conf.baseConfig.host);
      }
    });
    conn2.end();

    const conn3 = await base.createConnection({
      stream: (cb) => {
        cb();
      }
    });
    conn3.end();
  });

  it('connection error', function (done) {
    base
      .createConnection({
        host: 'www.facebook.com',
        port: 443,
        connectTimeout: 200,
        socketTimeout: 200
      })
      .then((conn) => {
        done(new Error('must have thrown error!'));
        conn.end();
      })
      .catch((err) => {
        if (err.code === 'ENOTFOUND' || err.code === 'ENETUNREACH') {
          // if no network access or IP¨v6 not allowed, just skip error
          done();
          return;
        }
        assert.isTrue(
          err.message.includes('socket timeout') || err.message.includes('Connection timeout'),
          err.message
        );
        assert.equal(err.sqlState, '08S01');
        assert.isTrue(err.errno === 45026 || err.errno === 45012);
        done();
      });
  });
  it('connection timeout', function (done) {
    base
      .createConnection({
        host: 'www.facebook.com',
        port: 443,
        connectTimeout: 1
      })
      .then((conn) => {
        done(new Error('must have thrown error!'));
        conn.end();
      })
      .catch((err) => {
        if (err.code !== 'ER_CONNECTION_TIMEOUT' && err.code !== 'ETIMEDOUT') {
          if (err.code === 'ENOTFOUND' || err.code === 'ENETUNREACH') {
            // if no network access or IP¨v6 not allowed, just skip error
            done();
            return;
          }
          console.log(err);
        }

        if (err.code === 'ER_CONNECTION_TIMEOUT') {
          assert.isTrue(err.message.includes('Connection timeout'));
        }
        assert.equal(err.sqlState, '08S01');
        assert.equal(err.errno, 45012);
        done();
      });
  });

  it('connection timeout connect (wrong url) with callback no function', (done) => {
    dns.resolve4('www.google.com', (err, res) => {
      if (err) done();
      else if (res.length > 0) {
        const host = res[0];
        const conn = base.createCallbackConnection({
          host: host,
          connectTimeout: 500
        });
        conn.connect((err) => {});
        conn.end();
        done();
      }
    });
  });

  it('connection without database', (done) => {
    base
      .createConnection({
        database: null
      })
      .then((conn) => {
        conn
          .query('SELECT DATABASE() as a')
          .then((res) => {
            assert.deepEqual(res, [{ a: null }]);
            conn.end();
            done();
          })
          .catch(done);
      })
      .catch(done);
  });

  it('connection timeout connect (wrong url) with promise', function (done) {
    const initTime = Date.now();
    dns.resolve4('www.google.com', function (err, res) {
      if (err) {
        // skipping since DNS not available
        done();
      } else if (res.length > 0) {
        const host = res[0];
        base
          .createConnection({ host: host, connectTimeout: 1000 })
          .then(() => {
            done(new Error('must have thrown error'));
          })
          .catch((err) => {
            if (err.code !== 'ER_CONNECTION_TIMEOUT' && err.code !== 'ETIMEDOUT') {
              if (err.code === 'ENOTFOUND' || err.code === 'ENETUNREACH') {
                // if no network access or IP¨v6 not allowed, just skip error
                done();
                return;
              }
              console.log(err);
            }
            if (err.code === 'ER_CONNECTION_TIMEOUT') {
              assert.isTrue(
                err.message.includes(
                  '(conn:-1, no: 45012, SQLState: 08S01) Connection timeout: failed to create socket after'
                )
              );
            }
            assert.isTrue(Date.now() - initTime >= 990, 'expected > 990, but was ' + (Date.now() - initTime));
            assert.isTrue(Date.now() - initTime < 2000, 'expected < 2000, but was ' + (Date.now() - initTime));
            done();
          });
      }
    });
  });

  it('connection timeout error (wrong url)', function (done) {
    const initTime = Date.now();
    dns.resolve4('www.google.com', (err, res) => {
      if (err) done();
      else if (res.length > 0) {
        const host = res[0];
        base.createConnection({ host: host, connectTimeout: 1000 }).catch((err) => {
          if (err.code !== 'ER_CONNECTION_TIMEOUT' && err.code !== 'ETIMEDOUT') {
            if (err.code === 'ENOTFOUND' || err.code === 'ENETUNREACH') {
              // if no network access or IP¨v6 not allowed, just skip error
              done();
              return;
            }
            console.log(err);
          }
          if (err.code === 'ER_CONNECTION_TIMEOUT') {
            assert.isTrue(
              err.message.includes(
                '(conn:-1, no: 45012, SQLState: 08S01) Connection timeout: failed to create socket after'
              )
            );
          }
          assert.isTrue(Date.now() - initTime >= 990, 'expected > 990, but was ' + (Date.now() - initTime));
          assert.isTrue(Date.now() - initTime < 2000, 'expected < 2000, but was ' + (Date.now() - initTime));
          done();
        });
      }
    });
  });

  it('changing session state', function (done) {
    if (
      (shareConn.info.isMariaDB() && !shareConn.info.hasMinVersion(10, 2, 2)) ||
      (!shareConn.info.isMariaDB() && !shareConn.info.hasMinVersion(5, 7, 4)) ||
      isMaxscale()
    ) {
      //session tracking not implemented
      this.skip();
    }
    if (!base.utf8Collation()) this.skip();

    base
      .createConnection()
      .then((conn) => {
        if (
          (shareConn.info.isMariaDB() && !shareConn.info.hasMinVersion(10, 3, 1)) ||
          (shareConn.info.isMariaDB() && shareConn.info.hasMinVersion(10, 2, 2))
        ) {
          //mariadb session tracking default value was empty before 10.3.1
          conn.query(
            'SET @@session_track_system_variables = ' +
              "'autocommit, character_set_client, character_set_connection, character_set_results, time_zone'"
          );
        }
        // assert.equal(conn.__tests.getCollation(), Collations.fromName('UTF8MB4_UNICODE_CI'));
        conn
          .query("SET time_zone = '+00:00', character_set_client = cp850")
          .then(() => {
            //encoding supported by iconv.js, but not by node.js
            assert.equal(conn.__tests.getCollation(), Collations.fromName('CP850_GENERAL_CI'));
            return conn.query("SET character_set_client = latin1, time_zone = '+01:00'");
          })
          .then(() => {
            //encoding supported by node.js
            assert.equal(conn.__tests.getCollation(), Collations.fromName('LATIN1_SWEDISH_CI'));
            return conn.end();
          })
          .then(() => done())
          .catch(done);
      })
      .catch(done);
  });

  function padStartZero(val, length) {
    val = '' + val;
    const stringLength = val.length;
    let add = '';
    while (add.length + stringLength < length) add += '0';
    return add + val;
  }

  it('connection.connect() error code validation callback', function (done) {
    this.timeout(10000);
    const conn = base.createCallbackConnection({
      user: 'fooUser',
      password: 'myPwd',
      allowPublicKeyRetrieval: true,
      connectTimeout: 1000
    });

    conn.on('error', (err) => {});
    conn.connect((err) => {
      if (!err) {
        done(new Error('must have thrown error'));
      } else {
        switch (err.errno) {
          case 45012:
            assert.equal(err.sqlState, '08S01');
            break;

          case 45025:
            //Client does not support authentication protocol
            assert.equal(err.sqlState, '08004');
            break;

          case 1251:
            //authentication method unavailable
            assert.equal(err.sqlState, '08004');
            break;

          case 1524:
            //GSSAPI plugin not loaded
            assert.equal(err.sqlState, 'HY000');
            break;

          case 1045:
            assert.equal(err.sqlState, '28000');
            break;

          case 1044:
            //mysql
            assert.equal(err.sqlState, '42000');
            break;

          case 1698:
            assert.equal(err.sqlState, '28000');
            break;

          default:
            done(err);
            return;
        }
        done();
      }
    });
  });

  it('connection.connect() error code validation promise', function (done) {
    this.timeout(10000);
    base
      .createConnection({ user: 'fooUser', password: 'myPwd', allowPublicKeyRetrieval: true })
      .then(() => {
        done(new Error('must have thrown error'));
      })
      .catch((err) => {
        switch (err.errno) {
          case 45012:
            //Client does not support authentication protocol
            assert.equal(err.sqlState, '08S01');
            break;
          case 45025:
            //Client does not support authentication protocol
            assert.equal(err.sqlState, '08004');
            break;

          case 1251:
            //authentication method unavailable
            assert.equal(err.sqlState, '08004');
            break;

          case 1524:
            //GSSAPI plugin not loaded
            assert.equal(err.sqlState, 'HY000');
            break;

          case 1045:
            assert.equal(err.sqlState, '28000');
            break;

          case 1044:
            //mysql
            assert.equal(err.sqlState, '42000');
            break;

          case 1698:
            assert.equal(err.sqlState, '28000');
            break;

          default:
            done(err);
            return;
        }
        done();
      });
  });

  it('connection error connect event', function (done) {
    const conn = base.createCallbackConnection({ user: 'fooUser' });
    conn.on('error', (err) => {});
    conn.connect((err) => {
      if (!err) {
        done(new Error('must have thrown error'));
      } else {
        done();
      }
    });
  });

  it('connection on error promise', function (done) {
    base
      .createConnection({ user: 'fooUser' })
      .then(() => {
        done(new Error('must have thrown error'));
      })
      .catch((err) => {
        done();
      });
  });

  it('connection validity', function (done) {
    let connOptionTemp = Conf.baseConfig;
    const conn = new Connection(new ConnOptions(connOptionTemp));

    assert.isTrue(!conn.isValid());
    conn
      .connect()
      .then(() => {
        assert.isTrue(conn.isValid());
        return new Promise(conn.end.bind(conn, null));
      })
      .then(() => {
        assert.isTrue(!conn.isValid());
        done();
      });
  });

  it('changing database', function (done) {
    let currDb = Conf.baseConfig.database;
    assert.equal(currDb, shareConn.info.database);
    shareConn
      .query('CREATE DATABASE IF NOT EXISTS changedb')
      .then(() => {
        return shareConn.query('USE changedb');
      })
      .then(() => {
        if (
          ((shareConn.info.isMariaDB() && shareConn.info.hasMinVersion(10, 2)) ||
            (!shareConn.info.isMariaDB() && shareConn.info.hasMinVersion(5, 7))) &&
          !isMaxscale()
        ) {
          //ok packet contain meta change
          assert.equal(shareConn.info.database, 'changedb');
        }
        shareConn.query('use ' + currDb);
        shareConn.query('DROP DATABASE changedb');
        done();
      })
      .catch(done);
  });

  it('pause socket', function (done) {
    shareConn.pause();
    const startTime = process.hrtime();
    setTimeout(() => {
      shareConn.resume();
    }, 500);

    shareConn
      .query("SELECT '1'")
      .then((rows) => {
        assert.deepEqual(rows, [{ 1: '1' }]);
        const diff = process.hrtime(startTime);
        //query has take more than 500ms
        assert.isTrue(diff[1] > 499000000, ' diff[1]:' + diff[1] + ' expected to be more than 500000000');
        done();
      })
      .catch(done);
  });

  it('pause socket callback', function (done) {
    const conn = base.createCallbackConnection();
    conn.connect((err) => {
      conn.pause();
      const startTime = process.hrtime();
      setTimeout(() => {
        conn.resume();
      }, 500);

      conn.query("SELECT '1'", (err, rows) => {
        if (err) {
          done(err);
        } else {
          assert.deepEqual(rows, [{ 1: '1' }]);
          const diff = process.hrtime(startTime);
          //query has take more than 500ms
          assert.isTrue(diff[1] > 499000000, ' diff[1]:' + diff[1] + ' expected to be more than 500000000');
          conn.end();
          done();
        }
      });
    });
  });

  it('charset change', async function () {
    if (!shareConn.info.isMariaDB()) {
      //session tracking not implemented
      this.skip();
    }
    const con = await base.createConnection({ charset: 'latin7' });
    await con.query('set names utf8mb3');
    assert.isTrue(con.info.collation.charset.includes('utf8'), con.info.collation.charset);
    await con.end();
  });

  it('error reaching max connection', async function () {
    // error occurs on handshake packet, with old error format
    if (isMaxscale()) this.skip();
    this.timeout(10000);

    const res = await shareConn.query('select @@max_connections as a');
    const limit = res[0].a;
    if (limit < 600) {
      const conns = [];
      try {
        for (let i = 0; i < limit + 10n; i++) {
          const con = await base.createConnection();
          conns.push(con);
        }
      } catch (err) {
        assert.equal(err.sqlState, 'HY000');
        assert.equal(err.errno, 1040);
        assert.equal(err.code, 'ER_CON_COUNT_ERROR');

        // now that all connection are use, destroy a query without creating a killing new connection
        conns[0].query(
          'select c1.* from information_schema.columns as c1, information_schema.tables, information_schema.tables as t2'
        );
        conns[0].destroy();
        await new Promise(function (resolve, reject) {
          setTimeout(async function () {
            for (let i = 0; i < conns.length; i++) {
              try {
                await conns[i].end();
              } catch (e) {
                //eat
              }
            }
            resolve();
          }, 2000);
        });
      }
    }
  });

  it('API escapeId error', function (done) {
    try {
      shareConn.escapeId('');
      done(new Error('should have thrown error!'));
    } catch (err) {
      assert.equal(err.sqlState, '0A000');
      assert.equal(err.code, 'ER_NULL_ESCAPEID');
      done();
    }
    try {
      shareConn.escapeId('\u0000ff');
      done(new Error('should have thrown error!'));
    } catch (e) {
      assert.equal(err.sqlState, '0A000');
      assert.equal(err.code, 'ER_NULL_CHAR_ESCAPEID');
      done();
    }
  });

  it('API escapeId', function () {
    const conn = base.createCallbackConnection();
    assert.equal(shareConn.escapeId('good_$one'), '`good_$one`');
    assert.equal(conn.escapeId('good_$one'), '`good_$one`');
    assert.equal(shareConn.escapeId('f:a'), '`f:a`');
    assert.equal(conn.escapeId('f:a'), '`f:a`');
    assert.equal(shareConn.escapeId('good_`è`one'), '`good_``è``one`');
    assert.equal(conn.escapeId('good_`è`one'), '`good_``è``one`');
    conn.end();
  });

  it('debug', function (done) {
    const conn = base.createCallbackConnection();
    conn.debug(true);
    conn.debug(false);
    conn.debugCompress(true);
    conn.debugCompress(false);
    conn.end();
    done();
  });

  it('API format error', function (done) {
    try {
      shareConn.format('fff');
      done(new Error('should have thrown error!'));
    } catch (err) {
      assert.equal(err.sqlState, '0A000');
      assert.equal(err.code, 'ER_NOT_IMPLEMENTED_FORMAT');
    }
    const conn = base.createCallbackConnection();
    try {
      conn.format('fff');
      done(new Error('should have thrown error!'));
    } catch (err) {
      assert.equal(err.sqlState, '0A000');
      assert.equal(err.code, 'ER_NOT_IMPLEMENTED_FORMAT');
      conn.end();
    }
    done();
  });

  it('connection error if user expired', function (done) {
    if (!shareConn.info.isMariaDB() || !shareConn.info.hasMinVersion(10, 4, 3) || isMaxscale()) {
      //session tracking not implemented
      this.skip();
    }
    if (!base.utf8Collation()) this.skip();
    shareConn.query("DROP USER IF EXISTS 'jeffrey'@'%'");
    shareConn.query('set global disconnect_on_expired_password= ON');
    shareConn.query("CREATE USER 'jeffrey'@'%' IDENTIFIED BY '5$?kLOPµ€rd' PASSWORD EXPIRE INTERVAL 1 DAY");
    shareConn.query('GRANT ALL ON `' + Conf.baseConfig.database + "`.* TO 'jeffrey'@'%'");
    shareConn.query('set @tstamp_expired= UNIX_TIMESTAMP(NOW() - INTERVAL 3 DAY)');
    shareConn.query(
      'update mysql.global_priv set\n' +
        "    priv=json_set(priv, '$.password_last_changed', @tstamp_expired)\n" +
        "    where user='jeffrey'"
    );
    shareConn.query('flush privileges').then(() => {
      base
        .createConnection({
          user: 'jeffrey',
          password: '5$?kLOPµ€rd'
        })
        .then((conn) => {
          done(new Error('must have thrown error !'));
        })
        .catch((err) => {
          shareConn.query('set global disconnect_on_expired_password= OFF');
          assert.equal(err.sqlState, 'HY000');
          assert.equal(err.code, 'ER_MUST_CHANGE_PASSWORD_LOGIN');
          done();
        });
    });
  });

  it('connection with expired user', function (done) {
    if (!shareConn.info.isMariaDB() || !shareConn.info.hasMinVersion(10, 4, 3) || isMaxscale()) {
      //session tracking not implemented
      this.skip();
    }
    if (!base.utf8Collation()) this.skip();
    shareConn.query("DROP USER IF EXISTS 'jeffrey'@'%'");
    shareConn.query('set global disconnect_on_expired_password= ON');
    shareConn.query("CREATE USER 'jeffrey'@'%' IDENTIFIED BY '5$?tuiHLKyklµ€rd' PASSWORD EXPIRE INTERVAL 1 DAY");
    shareConn.query('GRANT ALL ON `' + Conf.baseConfig.database + "`.* TO 'jeffrey'@'%'");
    shareConn.query('set @tstamp_expired= UNIX_TIMESTAMP(NOW() - INTERVAL 3 DAY)');
    shareConn.query(
      'update mysql.global_priv set\n' +
        "    priv=json_set(priv, '$.password_last_changed', @tstamp_expired)\n" +
        "    where user='jeffrey'"
    );
    shareConn.query('flush privileges').then(() => {
      base
        .createConnection({
          user: 'jeffrey',
          password: '5$?tuiHLKyklµ€rd',
          permitConnectionWhenExpired: true
        })
        .then((conn) => {
          conn
            .query("SET PASSWORD = PASSWORD('5$?tuiHLKyklµ€rdssss')")
            .then(() => {
              shareConn.query('set global disconnect_on_expired_password= OFF');
              conn.end();
              done();
            })
            .catch(done);
        })
        .catch(done);
    });
  });

  it('collation index > 255', async function () {
    if (isMaxscale()) this.skip();
    if (!shareConn.info.isMariaDB()) this.skip(); // requires mariadb 10.2+
    const conn = await base.createConnection({ collation: 'UTF8MB4_UNICODE_520_NOPAD_CI' });
    const res = await conn.query('SELECT @@COLLATION_CONNECTION as c');
    assert.equal(res[0].c, 'utf8mb4_unicode_520_nopad_ci');
    conn.end();
  });
});
