How to use the node-pg-migrate function in node-pg-migrate

private async migrateDb() {
    const config = postgresConfig();
    let client = new Client(Object.assign({}, config, { database: 'postgres' }));
    try {
      await client.connect();
      let response = await client.query(`select count(*)=1 as has_database from pg_database where datname=$1`, [
        config.database,
      ]);
      if (!response.rows[0].has_database) {
        await client.query(`create database ${safeName(config.database)}`);
      }
    } finally {
      client.end();
    }

    await migrate({
      direction: 'up',
      migrationsTable: 'migrations',
      singleTransaction: true,
      checkOrder: false,
      databaseUrl: {
        user: config.user,
        host: config.host,
        database: config.database,
        password: config.password,
        port: config.port,
      },
      count: Infinity,
      ignorePattern: '.*\\.(?!js)[^.]+',
      dir: join(__dirname, 'migrations'),
      log: (...args) => log.debug(...args),
    });

const migrateDatabase = async (event) => {
  try {
    const dbConnectionConfig = await getDbConnectionConfig()

    const dbClient = new Client(dbConnectionConfig)

    await dbClient.connect()

    const config = {
      dbClient,
      direction: event.direction || 'up',
      dir: 'migrations',
      migrationsTable: 'pgmigrations'
    }

    const migrationResponse = await pgMigrate(config)

    await dbClient.end()

    if (migrationResponse.length) {
      return {
        isBase64Encoded: false,
        statusCode: 200,
        body: JSON.stringify(migrationResponse)
      }
    }

    return {
      isBase64Encoded: false,
      statusCode: 200,
      body: JSON.stringify({ message: 'No migrations to run!' })
    }

try {
    dbConnectionConfig = await getDbConnectionConfig(dbConnectionConfig)
    dbConnectionConfig.database = 'uat-import-test'

    const dbClient = new Client(dbConnectionConfig)

    await dbClient.connect()

    const config = {
      dbClient,
      direction: event.direction || 'up',
      dir: 'migrations',
      migrationsTable: 'pgmigrations'
    }

    const migrationResponse = await pgMigrate(config)

    await dbClient.end()

    if (migrationResponse.length) {
      return {
        isBase64Encoded: false,
        statusCode: 200,
        body: JSON.stringify(migrationResponse)
      }
    }

    return {
      isBase64Encoded: false,
      statusCode: 200,
      body: JSON.stringify({ message: 'No migrations to run!' })
    }